Scandinavian Journal of Psychology, 2014, 55, 456–463
DOI: 10.1111/sjop.12150
Health and Disability Illness perception in people with chronic obstructive pulmonary disease CHRISTINE R AHEIM BORGE,1,2 TORBJØRN MOUM,3 MARTHA PULINE LEIN,2 ELISE LYNN AUSTEGARD2 and ASTRID KLOPSTAD WAHL1 1
Department of Health Sciences, University of Oslo, Norway Department of Medicine, Lovisenberg Diaconale Hospital, Oslo, Norway 3 Department of Behavioral Sciences in Medicine, University of Oslo, Norway 2
Borge, C. R., Moum, T., Lein, M. P., Austegard, E. L. & Wahl, A. K. (2014). Illness perception in people with chronic obstructive pulmonary disease. Scandinavian Journal of Psychology 55, 456–463. Illness perception (IP) concerns how patients evaluate living with a disease. To get a broader understanding of IP in patients with chronic obstructive pulmonary disease (COPD), we investigated whether breathlessness is an important precursor of IP and whether IP in its turn is related to mental health, physical health and global quality of life (QOL). One hundred and fifty-four patients with COPD participated in a cross-sectional survey. Participants underwent pulmonary function testing, provided socio-demographic and clinical information, and completed the following standardized instruments: Brief Illness Perception Questionnaire, Respiratory Quality of Life Questionnaire, Short-Form 12 Health Survey and the Quality of Life Scale. Multiple regression analyses were performed. A high IP score indicates that a patient believes that his/her illness represents a threat. Participants with a high score on the IP dimensions consequences, identity, concern and emotional representation, experienced more breathlessness. High scores on the IP dimensions consequences, identity and concern were associated with impaired physical health and high scores on the IP dimensions consequences, identity and emotional representation were associated with impaired mental health. Impaired global QOL was associated with high scores on the IP dimensions consequences, identity, concern, coherence and emotional representation. The strength of the associations between breathlessness and physical/mental health and global QOL decreased when certain dimensions of IP were included as predictors, indicating that IP to some extent acts as a mediating factor. These findings may have practical implications of patient counselling by helping COPD patients to cope with their disease by restructuring their personal models of illness. Key words: Chronic obstructive pulmonary disease, illness perception, breathlessness. Christine R aheim Borge, Department of Health Science, University of Oslo, Postboks 1089 Blindern, 0318 Oslo, Norway. Tel: +47 22845372; fax: +47 22845091; e-mail: [email protected] and Department of Medicine, Lovisenberg Diaconale Hospital Norway, 0440 Oslo, Norway. Tel: +47 23225000; e-mail: [email protected]
BACKGROUND Illness perception (IP) concerns a patient’s evaluation of the health threats posed by his/her illness. Such perceptions may influence coping, health and well-being (Leventhal, Meyer & Nerenz, 1980; Cameron & Leventhal, 2003). Leventhal and colleagues (1980; 2003) developed the common-sense model (CSM) based on previous research about how people evaluate their health threats. The model describes a parallel process in which fear and danger are adopted as symbols of your health situation when symptoms are experienced. Previous research has identified five dimensions of how patients with illness regard their own disease (Lau & Hartman, 1983; Leventhal et al., 1980). These dimensions are identity (label placed on the disease and symptoms associated with it), cause (thoughts about the cause of the disease), consequences (outcome of the disease), timeline (duration of disease) and control (beliefs about control or cure), and which have been investigated in illnesses such as rheumatoid arthritis, COPD, psoriasis (Scharloo, Kaptein, Weinman et al., 1998), asthma, diabetes and renal diseases (Broadbent, Petrie, Main & Ziebarth, 2006). Chronic obstructive pulmonary disease (COPD) is a burdensome chronic illness (GOLD (Global Initiative for Chronic Obstructive Lung Disease), 2013), and patients living with COPD may perceive many health threats, including the symptom of breathlessness/dyspnea (GOLD (Global Initiative for Chronic Obstructive Lung Disease), 2013). © 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd
The experience of breathlessness has been reported to be strongly associated with decreased quality of life (QOL) both in terms of mental and physical health in people with COPD (Bentsen, Henriksen, Wentzel-Larsen, Hanestad & Wahl, 2008; Moy, Reilly, Ries et al., 2009). For instance, a study by Braido, Baiardini, Menoni et al. (2011) found that dyspnea was the most relevant factor to cause disability in people with COPD. Further they found that patients with more disability reported higher levels of illness perception compared to people with COPD who were more self-sufficient. Scharloo, Kaptein, Schl€ osser et al. (2007) investigated the association between IP and QOL in COPD. They found that COPD patients with a more positive view of their illness also had better health related QOL and less breathing problems. A meta-analysis of the CSM supports these findings showing that those who have a higher perception of threats from illness also have impaired physical and psychological health (Hagger & Orbell, 2003). A recent study in COPD by Hartman, Boezen, de Greef and ten Hacken (2013) found that higher physical activity was associated with less airway obstruction, dyspnea and negative thoughts about the consequences of the disease. In addition, decreased lung function has been found to be associated with stronger perceptions of consequences from the disease (Fischer, Scharloo, Abbink et al., 2010). With regard to mental state, anxiety, panic and depression are common in COPD (Mikkelsen, Middelboe, Pisinger & Stage, 2004).
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Howard, Hallas, Wray and Carby (2009) investigated the relationship between panic and IP in patients with COPD and found that 63% of patients had experienced panic during the previous year. In addition, they found that younger patients experienced more emotional distress. In other diseases, such as cystic fibrosis, research has found that stronger perception of illness consequences was related to impaired psychosocial function (Sawicki, Sellers & Robinson, 2011). In a Norwegian study, results showed that people with COPD having more social support, perceived fewer consequences from the illness and understood more of their illness and also had a higher self-efficacy (Bonsaksen, Lerdal & Fagermoen, 2012). Summing up, previous research has found that sociodemographic and clinical variables are associated with IP, and that IP and COPD symptoms are associated with health and QOL. However, there is a need to look further into the mediating role of IP in the relationship between the symptom of breathlessness on the one hand and health and quality of life on the other. Such knowledge may give us a better understanding of how symptoms and perceived threats can impact on health and quality of life in COPD, and thus enable health care providers to develop strategies regarding how to assist COPD patients to improve their health status. Based on previous research in COPD and Leventhal’s CSM (Cameron & Leventhal, 2003), we have hypothesized that the symptom of breathlessness represents a perceived threat to control which may impact on IP in patients with COPD. IP represents the individual’s interpretation of danger, which, in turn, can be associated with health and QOL. In addition, demographic and clinical variables may be associated with breathlessness, IP and QOL Hence, in this paper we investigate whether breathlessness among patients with COPD is an important precursor of negative IP. We also examine whether IP is related to mental health, physical health and global QOL, controlling for demographic and clinical variables.
METHODS Study design and participants This study has a cross-sectional design, and it is part of a larger study on multiple symptoms, QOL and self-efficacy in patients with COPD. The study was approved by the Lovisenberg Diaconale Hospital administration and the Norwegian Social Science Service, and it was recommended by the Regional Committee for Medical Research Ethics for Southern Norway. The protocol complied with the Declaration of Helsinki. Up to date, two papers have been published from the larger study (Borge, Wahl & Moum, 2010, 2011). Out of the 502 COPD patients on a registered list in the outpatient unit of a medium-large hospital in Norway, 387 persons met the following inclusion criteria: diagnosed with COPD in the medical record; able to read and write Norwegian; and older than 30 years. Between June 2007 and March 2008, these 387 persons were invited by mail to participate in this study.
Instruments Questionnaire booklet. Patients completed a questionnaire booklet containing questions about clinical and socio-demographic characteristics (i.e., gender, age, living status, education level, smoking status, number of diseases) and standardized measurements of breathlessness, physical
© 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd
health, mental health, global QOL and IP. They completed the booklet at home and brought it to the hospital by appointment. We considered an acceptable rate of missing answers in the questionnaires to be ≤ 20%. The following standardized questionnaires were used: Illness perception was measured with the Brief Illness Perception Questionnaire (BIPQ) (Broadbent et al., 2006). It contains nine questions grouped into items for illness identity, cause, consequences, timeline and cure. These items are: consequences (item 1); timeline (item 2); personal control (item 3); treatment control (item 4); identity (item 5); coherence (item 7); emotional representation (item 8); and casual (item 9). Items 3, 4, and 7 are reversed before interpretation. The scale scores range from 0–10, with higher scores indicating a more threatening view of the illness. The BIPQ has previously been used in persons with asthma. The questionnaire was validated with 6 weeks test–retest reliabilities for the items that ranged from 0.42 to 0.75 (Broadbent et al., 2006). The questionnaire has been translated into Norwegian. Breathlessness was measured with the breathlessness subscale from the Respiratory Quality of Life Questionnaire (RQLQ) (Stavem, Erikssen & Boe, 1999). The questionnaire was originally designed by Marks, Dunn and Woolcock (1992) and Marks, Burney, Premaratne, Simpson and Webb (1997) in Australia, and it has been used in asthma patients. It has been translated into Norwegian, and Stavem et al. (1999) have used it in Norwegian COPD patients. The questionnaire has 20 questions and four subscales with scores that range from 0–10: breathlessness, mood, concerns and social. Each item is measured on a 5-point scale: “not at all,” “mildly,” “moderately,” “severely” and “very severely.” Physical health and mental health conceptualized as health related quality of life were measured with the Short-Form 12 version 2 health survey (SF-12v2) (Ware, Kosinski & Keller, 1996). This questionnaire consists of 12 items that measure physical and mental health. Higher scores indicate better health. Previous studies have reported satisfactory results for the SF-12’s reliability and validity (Ware et al., 1996).The scores was calculated under a license scoring program (License number: QM006198). Global Quality of Life was measured by the Quality of Life Scale (QOLS) (Burckhardt, Woods, Schultz & Ziebarth, 1989). The QOLS contains 16 items that ask about overall satisfaction in domains of life such as health, work, leisure and independence. The items are scored on a 7-point Likert scale with a combined overall score ranging from 16–112. Higher scores indicate better overall perceived QOL. The questionnaire has been used in various patient populations in Norway, including patients with psoriasis (Wahl, Burckhardt, Wiklund & Hanestad, 1998) and cystic fibrosis (Wahl, Rustøen, Hanestad, Gjengedal & Moum, 2005). Physical tests. Forced expiratory volume in one second (FEV1) was measured with a spirometry test (VMax spirometry, SensorMedics, USA, with European standard measurement) according to the American Thoracic Society standard for lung function testing (Pellegrino, Viegi, Brusasco et al., 2005).
Statistical analysis Frequencies, means and standard deviations (SDs) were analyzed for the socio-demographic variables, clinical variables and self-reported data from the questionnaires. In order to analyze the relationship between demographic variables, social variables, clinical variables and the scores from the questionnaire for breathlessness, physical health, mental health, global QOL and IP, we used bivariate correlations (Person’s r) and hierarchical multiple linear regression analyses. We used IP dimensions (i.e., consequences, timeline, personal control, treatment control, identity, concern coherence, emotional representation) as dependent variables in separate multiple linear regression analyses using predicted lung function (FEV1%) and breathlessness as independents and controlling for age and gender. Further we used mental health score, physical health score and global QOL score as dependent variables in separate hierarchical multiple linear regression analyses controlling for step 1; age, gender, FEV1% and breathlessness and step 2; age, gender, FEV% and illness perception
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dimensions (separately), step 3; age, gender, FEV1%, breathlessness, and illness perception dimensions (separately). Standardized Beta (st. ß) is reported in the analysis. Possible mediator effects and the illness perception items were tested for significance using the Sobel test. Statistical significance was set at 5%, and all analyses were performed with IBM SPSS Statistics 20 (IBM, Armonk, NY).
Characteristics of dependent variables: IP, breathlessness, physical health, mental health and global QOL Table 2 presents the descriptive information for illness perception (BIPQ), breathlessness (RQLQ), physical health and mental health (SF-12), and global quality of life (QOLS). For further information see Table 2.
RESULTS The association between breathlessness and IP, controlling for demographic and clinical variables
Participants Out of the 168 people who agreed to participate, four persons were unable to complete the questionnaire, four did not return it and six withdrew their consent. Thus, 154 people (40% response rate) were included in the study.
Reliability of the questionnaires Cronbach’s alphas for the breathlessness subscale of the Respiratory Quality of Life Questionnaire and for the Global QOL of the Quality of Life Scale were both 0.87 in the present sample.
Characteristics of the sample: Socio-demographic and clinical variables
Table 2. Descriptors of breathlessness and score of questionnaires
Table 1 presents the socio-demographic and clinical variables. The mean age of the participants was 64.6 years, 51.3% were males, and 44.2% reported that they are still smokers. The mean predicted lung function was 59.1%, and the mean number of comorbidities was 1.9. For further information see Table 1. Table 1. Descriptors of demographic, social and clinical variables Variables
N (%)
Mean (SD)
Min–Max
Age (years) Gender: Male Female Education: Primary school (1) Vocational school (2) Secondary school (3) University < 4 years (4) University > 4 years (5) Living status: Living with someone Living alone Smoking: Yes No Number of co-morbidities Predicted lung function FEV1% Mild stage of COPD (FEV1% ≥ 80) Moderate stage of COPD (50% ≤ FEV1% < 80) Severe stage of COPD (30 ≤ FEV1% < 50) Very severe stage of COPD (FEV1% < 30)
154 154 79 75 152 35 27 47 28 15 154 77 77 154 68 86 154
(100) (100) (51.3) (48.7) (98.7) (22.7) (17.5) (30.5) (18.2) (9.7) (100) (50) (50) (100) (44.2) (55.8) (100)
64.6 (10.2)
36–87
154 (100)
59.1 (22.6)
2.7 (1.3)
1.9 (1.4)
The results of the bivariate analyses (Fig. 1) show that the IP items; consequences, identity, concern and emotional representation are significantly related to lower lung function (r = –0.21– –0.48, p < 0.01–0.001) and more symptoms of breathlessness (r = 0.44–0.67, p < 0.01–0.001). Further, a lower lung function is significantly related to higher scores of the IP item timeline (r = –0.19, p < 0.05, Fig. 1). In the regression analyses with IP items as the dependent variables, there were no significant relationships between IP scores and the demographic variables (Table 3). However, a lower predicted lung function is significantly associated with a higher IP
Variables
N
Mean (SD)
Range
Score for each Illness Perception item: 1. How much does your illness affect your life?
153
5.9 (2.6)
1–10
2. How long do you think your illness will continue?
150
9.3 (1.7)
1–10
3. How much control do you feel you have over your illness?
153
5.6 (2.5)
1–10
4. How much do you think your treatment can help your illness?
146
4.5 (2.6)
1–10
5. How much do you experience symptoms from your illness?
153
5.9 (2.2)
1–10
6. How concerned are you about your illness?
153
5.6 (2.9)
1–10
7. How well do you feel you understand your illness?
153
4.0 (2.5)
1–10
8. How much does your illness affect you emotionally? (e.g., does it make you angry, scared, upset or depressed?
153
Breathlessness (Possible score from 0–10) Physical health (SF-12, PCS) (Possible score from 0–100) Mental health (SF-12, MCS) (Possible score from 0–100) Global quality of life (Possible score from 16–112)
153
2.4 (2.1)
144
32.4 (10.8)
4.6–56.8
154
47 (12.3)
13.5–72.6
154
80.3 (14.1)
35–110
1–5
0–7 17–124
28 (18) 72 (46.8) 39 (25.3) 15 (9.7)
© 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd
48 (2.8)
1–10
0–7.5
Illness perception in people with COPD 459
Scand J Psychol 55 (2014)
r= - 0.43*** FEV1% r=0.67 *** Breathlessness
r= - 0.19* FEV1 %
r= - 0.62*** Physical health r= - 0.26** Mental health r= - 0.38*** Global quality of life
Consequences Timeline
Personal control
Treatment control r= - 0.48*** FEV1% r=0.62*** Breathlessness
r= - 0.24*** FEV1% r=0.44** Breathlessness
r= - 0.50*** Physical health r= - 0.30** Mental health r= - 0.31**** Global quality of life
Identity
r= - 0.31*** Physical health r= - 0.19*Mental health r= - 0.31** Global quality of life
Concern
Coherence
r= - 0.21** FEV1% r=0.45*** Breathlessness
r= - 0.21*Global quality of life
Emotional
r= - 0.20** Physical health r= - 0.55*** Mental health r= - 0.47***Global quality of life
representation
Notes: Breathlessness: higher score= more problems with breathlessness, IP score (consequences, timeline, personal control treatment control identity, concern, coherence, emotional representation) higher score = higher perceived threats from illness, Physical health and Mental health: higher score = fewer health problems, Global quality of life: higher score = better quality of life. * p < 0.05, ** p < 0.01, *** p < 0.001.
Fig. 1. Bivariate relationship between lung function (FEV1%), breathlessness, brief illness perception questionnaire, physical health, mental health and global quality of life. Pearson’s r.
score with regard to the items consequences (st. b = –0.19, p < 0.05) and identity (st. b = –0.28, p < 0.001). More symptoms of breathlessness are associated with a higher IP score on the items consequences (st. b = 0.62, p < 0.001), identity (st. b = 0.51, p < 0.001), concern (st. b = 0.40, p < 0.001) and emotional representation (st. b = 0.37, p < 0.001). The adjusted variances of the significantly associated variables explain 50% for consequences, 45% for identity, 19% for concern and 21% for emotional representation. The Sobel test shows that predicted lung function becomes significantly lower ( p < 0.001) or vanish as a significant predictor when breathlessness is entered in the equations (see Fig. 1) in which the dependent variables are consequences, identity, concern and emotional representation, indicating that breathlessness acted as mediator between predicted lung function and illness perception in these cases (Table 3).
The associations between IP and mental health, physical health and global QOL, controlling for demographic, clinical variables and breathlessness The results of the bivariate analyses (Fig. 1) show that higher scores on IP items; consequences, identity, concern and emotional representation are significantly related to impaired physical health (r = –0.20 – –0.62, p < 0.05–0.001), mental health (r = –0.19 – –0.55, p < 0.05–0.01) and global QOL (r = –0.31 – –0.47, p < 0.01–0.001). In addition, higher levels on IP coherence are significantly related to impaired global QOL (r = –0.21, p < 0.05). Table 4, shows the multiple regression analysis between IP items, breathlessness, FEV1% and physical health, mental health and global QOL, controlling for age and gender. More breathlessness is significantly related to impaired physical health (st. b = –0.52, p < 0.001), mental health (st. b = –0.32, p < 0.01) and global QOL (st. b = –0.39, p < 0.001).
Table 3. Predicting illness perception by breathlessness and predicted lung function (FEV1%). Multiple linear regressions with controls for age and gender. Standardized betas and explained variance
Consequences (BIPQ 1)b ᵇ St ß FEV1% Breathlessnessa Adjusted R²
0.19* 0.62*** 0.50
Timeline (BIPQ 2)b ᵇ St ß 0.18 0.05 0.04
Personal control (BIPQ 3)bᵇ St ß 0.03 0.00 0.03
Treatment control (BIPQ 4)b ᵇ St ß 0.14 0.05 0.00
Identity (BIPQ 5)b ᵇ St ß
Concern (BIPQ 6)b ᵇ St ß
0.28*** 0.51*** 0.45
0.12 0.40*** 0.19
Coherence (BIPQ 7)b ᵇ St ß 0.10 0.09 0.01
Emotional representation (BIPQ 8)b ᵇ St ß 0.15 0.37*** 0.21
Notes: a higher score = more problems with breathlessness,ᵇb higher score = higher perceived threats from illness, *p < 0.05, ***p < 0.001. Age and gender showed no significant effects in any of the equations (i.e., when predicted lung function and breathlessness was controlled). © 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd
© 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd b
–0.15 0.07
–0.04 0.05
–0.27** 0.11
–0.52*** 0.25
0.05 0.03
–0.11 0.06
–0.10 0.07
–0.63*** 0.37
Step 2
–0.22* –0.49*** 0.39 –0.50*** –0.08 0.27 –0.52*** –0.11 0.28 –0.51*** 0.03 0.25 –0.36*** –0.33** 0.33 –0.48*** –0.10 0.28 –0.53*** –0.07 0.27 –0.53*** –0.04 0.27
Step 3 –0.32** 0.13
Step 1
–0.53*** 0.30
–0.13 0.07
–0.13 0.07
–0.30** 0.12
–0.01 0.05
0.03 0.05
0.13 0.07
–0.25** 0.10
Step 2
Mental healthc ᶜ
d
–0.39*** 0.16
Step 1
–0.44*** 0.22
–0.21* 0.08
–0.24** 0.09
–0.33** 0.12
–0.13 0.06
0.02 0.04
–0.09 0.06
–0.41*** 0.17
Step 2
Global quality of lifed ᵈ
higher score = better quality of life,
–0.28* –0.08 0.13 –0.32*** 0.14 0.15 –0.32*** 0.03 0.13 –0.33*** –0.02 0.14 –0.24* –0.17 0.15 –0.31** –0.03 0.13 –0.34*** –0.15 0.15 –0.15 –0.48*** 0.31
Step 3
higher score = higher perceived threats from illness, ᶜ c higher score = fewer health problems, ᵈ
–0.52*** 0.28
Breathlessnessa Adjusted R² Breathlessnessa Consequences (BIPQ-1)b ᵇ Adjusted R² Breathlessnessa Timeline (BIPQ-2)b ᵇ Adjusted R² Breathlessnessa Personal control (BIPQ-3)b ᵇ Adjusted R² Breathlessnessa Treatment control (BIPQ-4)b ᵇ Adjusted R² Breathlessnessa Identity (BPIQ-5)b ᵇ Adjusted R² Breathlessnessa Concern (BIPQ-6)b ᵇ Adjusted R² Breathlessnessa Coherence (BIPQ-7)b ᵇ Adjusted R² Breathlessnessa Emotional representation (BIPQ-8)b ᵇ Adjusted R²
Independent variable breathlessness: Independent variable breathlessness and IP:
Notes: a higher score = more problems with breathlessness,ᵇ *p < 0.05, **p < 0.01, ***p < 0.001.
Step 1
Standardized betas
Variables↓
Physical healthc ᶜ
–0.21* –0.28** 0.20 –0.36*** –0.07 0.16 –0.39*** 0.02 0.16 –0.38*** –0.15 0.18 –0.31** –0.16 0.17 –0.34*** –0.14 0.18 –0.41*** –0.22* 0.21 –0.26** –0.35*** 0.26
Step 3
Table 4. Direct and indirect effects of breathlessness and illness perception on dependent variables. Multiple linear regression analyses with standardized betas and explained variance. All coefficients controlled for age, gender and FEV 1%
460 C. R. Borge et al. Scand J Psychol 55 (2014)
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The explained variance is 28% for physical health, 13% for mental health and 16% for global QOL (step 1, Table 4). In the equations, higher scores on the IP items; consequences (st. b = –0.63, p < 0.001), identity (st. b = –0.52 p < 0.001) and concern (st. b = –0.27, p < 0.01) are significantly related to impaired physical health (step 2, Table 4). The adjusted variances of the significantly associated variables explain 37% for consequences, 25% for identity and 11% for concern in physical health. Further higher scores on the IP items; consequences (st. b = –0.25, p < 0.01), identity (st. b = –0.30, p < 0.01) and emotional representation (st. b = –0.53, p < 0.001) are significantly related to impaired mental health (step 2, Table 4). The adjusted variances of the significantly associated variables explain 10% for consequences, 12% for identity and 30% for emotional representation in mental health. Finally, impaired global QOL is associated with higher IP scores on the items consequences (st. b = –0.41, p < 0.001), identity (st. b = –0.33, p < 0.01), concern (st. b = –0.24, p < 0.01), coherence (st. b = –0.21, p < 0.05) and emotional representation (st. b = –0.44, p < 0.001) (step 2, Table 4). The adjusted variances of the significantly associated variables explain 17% for consequences, 12% for identity, 9% for concern, 8% for coherence and 22% for emotional representation in global QOL. After entering breathlessness and IP items in step 3 the st. b for breathlessness was significantly reduced in the equations (sobel test) for (1) consequences and physical health, (2) identity and physical health, (3) emotional representation and mental health, and (4) consequences and global QOL compared to step 1, indicating that the said IP items acted as mediators in the those relationships (Table 4). In the other 19 equations we found no mediator effect of the IP items.
DISCUSSION Our findings support the assumptions in the CSM and the expected pattern of breathlessness being associated with certain dimensions of IP (greater perceived threat from the illness), and several dimensions of IP being associated with poorer health and QOL. In this study we found that people with COPD who experienced more breathlessness also perceived more consequences, higher identity of symptoms, were more concerned and reported a higher emotional representation of the disease. The explained variance in IP was highest for those who experienced more consequences (50%) from their disease and identified more symptoms (45%) from their disease. This indicates that the experience of breathlessness has an important impact on how people with COPD think about their disease. They may experience consequences in various ways such as pulmonary infections, coughing and sputum (Hill, Goldstein, Guyatt et al., 2010). A person might not know that he/she has COPD because shortness of breath comes on only gradually. It is well known that people with COPD often wait to contact their doctor until they start becoming aware of increased breathlessness, and by then their pulmonary function has already become chronically debilitated (GOLD, 2013; Hill et al., 2010). In our study, we found bivari© 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd
Illness perception in people with COPD 461 ate associations between decreased lung function and higher IP of the dimensions consequences, timeline, identity, concern and emotional representation. Further breathlessness emerged as a mediator in the relationship between predicted lung function and the IP dimensions consequences, identity, concern and emotional representation. Our results are interesting, since in previous research we have only found evidence of a bivariate association between the dimension emotional representation (Howard et al., 2009) and consequences with low predicted lung function (Howard et al., 2009; Fischer et al., 2010). As explained by the CSM, decreased pulmonary function may lead to fear of breathlessness, which in turn may impact on how COPD patients focus on the consequences of the disease and fear that the disease will last for a long time and that more symptoms are expected which in its turn will lead to greater concern and representation of emotional distress. The results from our study show that those who report poor physical health also experienced more consequences, identified more symptoms, and were more concerned about their disease. Hartman et al. (2013) found similar results; namely, that those being less physically active also experienced more consequences and were more concerned about their disease. Scharloo et al. (2007) also found a relationship with the dimension consequences, but in addition with timeline which surprisingly we did not find. Our results could be explained by the fact that a majority of our patients had a moderate stage of disease (46.8%). On this background they might still be rather optimistic about their disease, entertaining hopes of getting better (Philip, Gold, Brand, Douglass, Miller & Sundararajan, 2012). Mental health scores were negatively affected by patients who perceived more consequences from their disease, identified more symptoms and reported higher emotional representation. Similar results are reported by Scharloo et al. (2007) who find an association between high IP scores (using the subscales “illness identity,” “emotional representations” and “causal attributions”) and increased mental health problems in COPD patients. With respect to breathlessness, we found a significant relationship to poorer mental health, which is consistent with research by Moy et al. (2009), who reported that breathlessness in COPD is significantly related to more mental health problems. The “global quality of life” concept used in this study (Burckhardt et al., 1989) refers to how happy people are with respect to their economic situation, work and relationships with friends and family. In our study, we found that several of the IP dimensions were related to reduced global QOL (i.e., consequences, identity, concern, coherence, emotional representation). We have not found any other studies that have examined how global QOL is related to IP in COPD patients. However, it seems reasonable that the more one perceives COPD as a threat, the worse one’s global QOL will be. The effect of breathlessness became significantly weaker only in few of the equations in which IP was introduced as an additional independent, that is, the effects on physical health (reduced by consequences, identity), mental health (reduced by emotional representation) and global QOL (reduced by consequences and global QOL) indicating that IP acted as a mediating
462 C. R. Borge et al. factor in the said associations. Thus most of the IP items show direct relationships with QOL and these relationships are not confounded by breathlessness nor do they mediate the impact of breathlessness which retains its direct effects in most cases. Given the results of this study, it may be worthwhile to focus on IP in COPD health care interventions such as rehabilitation and patient education as a focus like this could help to reduce the impact of symptoms. An example of such an intervention was reported by Broadbent, Ellis, Thomas, Gamble and Petrie (2009), who showed that a tailored IP intervention helps myocardial infarction patients get back to work and also gain a better understanding of their condition. Furthermore, teaching patients to be physically active could reduce fear, which is part of the reasoning behind physical training, mental assessment and pulmonary rehabilitation programs in COPD treatment (Troosters, Casaburi, Gosselink & Decramer, 2005). However, it may be necessary to develop broader IP interventions, including how to motivate patients to change their illness perceptions, especially with respect to evaluating their disease as less threatening. For example, such an intervention could be included in regular conversations with patients and their spouses before and after hospitalizations, or as a regular component of self-management pulmonary rehabilitation programs. Teaching COPD patients strategies to control their symptoms of breathlessness for example by means of breathing control exercises might also be a strategy to influence illness perception in patients with COPD.
STRENGTHS AND LIMITATIONS There are several limitations to this study. First, the crosssectional design does not allow us to make causal inferences about the relationships reported here. Second, the response rate was rather low (40%), partly because the inclusion criteria required participants to speak and write Norwegian, and partly because COPD patients at all stages of the disease were allowed to participate. The first requirement may have limited participation because the outpatient list used for this study was for an area of Norway where there are many minority speaking people, and the second criterion meant that patients in more advanced stages of COPD may not have had the energy to participate. We used an early version of the Norwegian BIPQ that had a scale from 1–10 and not 0–10. This may have resulted in a higher IP. However, separate analyses show that the patients in our study scoring 1 were of low frequency with a mean of 5%. On this background we believe that our result might not have been influenced much by the missing value 0 in the scale.
CONCLUSIONS We found that patients with COPD who experience a high degree of breathlessness also perceive COPD to be more threatening. For most IP domains higher scores were associated with more physical health problems, mental health problems and a lower global QOL. Our data also indicated that only few of the IP items act as mediators in the relationship between breathlessness and physical/mental health and global QOL. © 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd
Scand J Psychol 55 (2014)
Our results suggest the possibilities of interventions aiming to help people with COPD to manage their symptoms, be more realistic about their disease and understand its consequences. Tailoring IP interventions along these lines might help COPD patients restructure their perceptions of COPD, which, in turn, even could help to reduce symptoms of breathlessness and increase physical activity and QOL. CB and AW were responsible for the study conception, design and data collection. CB, AW and TM performed the analysis. All authors were responsible for writing and revisions of the manuscript. There are no conflicts of interest in this study.
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Scand J Psychol 55 (2014) Howard, C., Hallas, C. N., Wray, J. & Carby, M. (2009). The relationship between illness perceptions and panic in chronic obstructive pulmonary disease. Behaviour Research and Therapy, 47, 71–76. Lau, R. R. & Hartman, K. A. (1983). Common sense representations of common illnesses. Health Psychology, 2, 167–185. Leventhal, H., Meyer, D. & Nerenz, D. (1980). The common sense representation of illness danger. In S. Rachman (Ed.), Contributions to medical psychology (Vol. 2, pp. 7–30). New York: Pergamon. Marks, G. B., Burney, P. G., Premaratne, U. N., Simpson, J. & Webb, J. (1997). Asthma in Greenwich, UK: Impact of the disease and current management practices. The European Respiratory Journal, 10, 1224–1229. Marks, G. B., Dunn, S. M. & Woolcock, A. J. (1992). A scale for the measurement of quality of life in adults with asthma. Journal of Clinical Epidemiology, 45, 461–472. Mikkelsen, R. L., Middelboe, T., Pisinger, C. & Stage, K. B. (2004). Anxiety and depression in patients with chronic obstructive pulmonary disease (COPD). A review. Nordic Journal of Psychiatry, 58, 65–70. Moy, M. L., Reilly, J. J., Ries, A. L., Mosenifar, Z., Kaplan, R. M., Lew, R. et al. (2009). Multivariate models of determinants of health-related quality of life in severe chronic obstructive pulmonary disease. Journal of Rehabilitation Research and Development, 46, 643–654. Pellegrino, R., Viegi, G., Brusasco, V., Crapo, R. O., Burgos, F., Casaburi, R. et al. (2005). Interpretative strategies for lung function tests. The European Respiratory Journal, 26, 948–968. Philip, J., Gold, M., Brand, C., Douglass, J., Miller, B. & Sundararajan, V. (2012). Negotiating hope with chronic obstructive pulmonary disease patients: A qualitative study of patients and healthcare professionals. Internal Medicine Journal, 42, 816–822.
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Illness perception in people with COPD 463 Sawicki, G. S., Sellers, D. E. & Robinson, W. M. (2011). Associations between illness perceptions and health-related quality of life in adults with cystic fibrosis. Journal of Psychosomatic Research, 70, 161–167. Scharloo, M., Kaptein, A. A., Schl€ osser, M., Pouwels, H., Bel, E. H., Rabe, K. F. & Wouters, E. F. (2007). Illness perceptions and quality of life in patients with chronic obstructive pulmonary disease. The Journal of Asthma, 44, 575–581. Scharloo, M., Kaptein, A. A., Weinman, J., Hazes, J. M., Willems, L. N., Bergman, W. & Rooijmans, H. G. (1998). Illness perceptions, coping and functioning in patients with rheumatoid arthritis, chronic obstructive pulmonary disease and psoriasis. Journal of Psychosomatic Research, 44, 573–585. Stavem, K., Erikssen, J. & Boe, J. (1999). Performance of a short lungspecific health status measure in outpatients with chronic obstructive pulmonary disease. Respiratory Medicine, 93, 467–475. Troosters, T., Casaburi, R., Gosselink, R. & Decramer, M. (2005). Pulmonary rehabilitation in chronic obstructive pulmonary disease. American Journal of Respiratory and Critical Care Medicine, 172, 19–38. Wahl, A., Burckhardt, C., Wiklund, I. & Hanestad, B. R. (1998). The Norwegian version of the Quality of Life Scale (QOLS–N). A validation and reliability study in patients suffering from psoriasis. Scandinavian Journal of Caring Sciences, 12(4), 215–222. Wahl, A. K., Rustøen, T., Hanestad, B. R., Gjengedal, E. & Moum, T. (2005). Living with cystic fibrosis: Impact on global quality of life. Heart & Lung, 34, 324–331. Ware, J. Jr, Kosinski, M. & Keller, S. D. (1996). A 12-item short-form health survey: Construction of scales and preliminary tests of reliability and validity. Medical Care, 34, 220–233. Received 10 July 2013, accepted 21 May 2014
DOI: 10.1111/sjop.12150
Health and Disability Illness perception in people with chronic obstructive pulmonary disease CHRISTINE R AHEIM BORGE,1,2 TORBJØRN MOUM,3 MARTHA PULINE LEIN,2 ELISE LYNN AUSTEGARD2 and ASTRID KLOPSTAD WAHL1 1
Department of Health Sciences, University of Oslo, Norway Department of Medicine, Lovisenberg Diaconale Hospital, Oslo, Norway 3 Department of Behavioral Sciences in Medicine, University of Oslo, Norway 2
Borge, C. R., Moum, T., Lein, M. P., Austegard, E. L. & Wahl, A. K. (2014). Illness perception in people with chronic obstructive pulmonary disease. Scandinavian Journal of Psychology 55, 456–463. Illness perception (IP) concerns how patients evaluate living with a disease. To get a broader understanding of IP in patients with chronic obstructive pulmonary disease (COPD), we investigated whether breathlessness is an important precursor of IP and whether IP in its turn is related to mental health, physical health and global quality of life (QOL). One hundred and fifty-four patients with COPD participated in a cross-sectional survey. Participants underwent pulmonary function testing, provided socio-demographic and clinical information, and completed the following standardized instruments: Brief Illness Perception Questionnaire, Respiratory Quality of Life Questionnaire, Short-Form 12 Health Survey and the Quality of Life Scale. Multiple regression analyses were performed. A high IP score indicates that a patient believes that his/her illness represents a threat. Participants with a high score on the IP dimensions consequences, identity, concern and emotional representation, experienced more breathlessness. High scores on the IP dimensions consequences, identity and concern were associated with impaired physical health and high scores on the IP dimensions consequences, identity and emotional representation were associated with impaired mental health. Impaired global QOL was associated with high scores on the IP dimensions consequences, identity, concern, coherence and emotional representation. The strength of the associations between breathlessness and physical/mental health and global QOL decreased when certain dimensions of IP were included as predictors, indicating that IP to some extent acts as a mediating factor. These findings may have practical implications of patient counselling by helping COPD patients to cope with their disease by restructuring their personal models of illness. Key words: Chronic obstructive pulmonary disease, illness perception, breathlessness. Christine R aheim Borge, Department of Health Science, University of Oslo, Postboks 1089 Blindern, 0318 Oslo, Norway. Tel: +47 22845372; fax: +47 22845091; e-mail: [email protected] and Department of Medicine, Lovisenberg Diaconale Hospital Norway, 0440 Oslo, Norway. Tel: +47 23225000; e-mail: [email protected]
BACKGROUND Illness perception (IP) concerns a patient’s evaluation of the health threats posed by his/her illness. Such perceptions may influence coping, health and well-being (Leventhal, Meyer & Nerenz, 1980; Cameron & Leventhal, 2003). Leventhal and colleagues (1980; 2003) developed the common-sense model (CSM) based on previous research about how people evaluate their health threats. The model describes a parallel process in which fear and danger are adopted as symbols of your health situation when symptoms are experienced. Previous research has identified five dimensions of how patients with illness regard their own disease (Lau & Hartman, 1983; Leventhal et al., 1980). These dimensions are identity (label placed on the disease and symptoms associated with it), cause (thoughts about the cause of the disease), consequences (outcome of the disease), timeline (duration of disease) and control (beliefs about control or cure), and which have been investigated in illnesses such as rheumatoid arthritis, COPD, psoriasis (Scharloo, Kaptein, Weinman et al., 1998), asthma, diabetes and renal diseases (Broadbent, Petrie, Main & Ziebarth, 2006). Chronic obstructive pulmonary disease (COPD) is a burdensome chronic illness (GOLD (Global Initiative for Chronic Obstructive Lung Disease), 2013), and patients living with COPD may perceive many health threats, including the symptom of breathlessness/dyspnea (GOLD (Global Initiative for Chronic Obstructive Lung Disease), 2013). © 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd
The experience of breathlessness has been reported to be strongly associated with decreased quality of life (QOL) both in terms of mental and physical health in people with COPD (Bentsen, Henriksen, Wentzel-Larsen, Hanestad & Wahl, 2008; Moy, Reilly, Ries et al., 2009). For instance, a study by Braido, Baiardini, Menoni et al. (2011) found that dyspnea was the most relevant factor to cause disability in people with COPD. Further they found that patients with more disability reported higher levels of illness perception compared to people with COPD who were more self-sufficient. Scharloo, Kaptein, Schl€ osser et al. (2007) investigated the association between IP and QOL in COPD. They found that COPD patients with a more positive view of their illness also had better health related QOL and less breathing problems. A meta-analysis of the CSM supports these findings showing that those who have a higher perception of threats from illness also have impaired physical and psychological health (Hagger & Orbell, 2003). A recent study in COPD by Hartman, Boezen, de Greef and ten Hacken (2013) found that higher physical activity was associated with less airway obstruction, dyspnea and negative thoughts about the consequences of the disease. In addition, decreased lung function has been found to be associated with stronger perceptions of consequences from the disease (Fischer, Scharloo, Abbink et al., 2010). With regard to mental state, anxiety, panic and depression are common in COPD (Mikkelsen, Middelboe, Pisinger & Stage, 2004).
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Howard, Hallas, Wray and Carby (2009) investigated the relationship between panic and IP in patients with COPD and found that 63% of patients had experienced panic during the previous year. In addition, they found that younger patients experienced more emotional distress. In other diseases, such as cystic fibrosis, research has found that stronger perception of illness consequences was related to impaired psychosocial function (Sawicki, Sellers & Robinson, 2011). In a Norwegian study, results showed that people with COPD having more social support, perceived fewer consequences from the illness and understood more of their illness and also had a higher self-efficacy (Bonsaksen, Lerdal & Fagermoen, 2012). Summing up, previous research has found that sociodemographic and clinical variables are associated with IP, and that IP and COPD symptoms are associated with health and QOL. However, there is a need to look further into the mediating role of IP in the relationship between the symptom of breathlessness on the one hand and health and quality of life on the other. Such knowledge may give us a better understanding of how symptoms and perceived threats can impact on health and quality of life in COPD, and thus enable health care providers to develop strategies regarding how to assist COPD patients to improve their health status. Based on previous research in COPD and Leventhal’s CSM (Cameron & Leventhal, 2003), we have hypothesized that the symptom of breathlessness represents a perceived threat to control which may impact on IP in patients with COPD. IP represents the individual’s interpretation of danger, which, in turn, can be associated with health and QOL. In addition, demographic and clinical variables may be associated with breathlessness, IP and QOL Hence, in this paper we investigate whether breathlessness among patients with COPD is an important precursor of negative IP. We also examine whether IP is related to mental health, physical health and global QOL, controlling for demographic and clinical variables.
METHODS Study design and participants This study has a cross-sectional design, and it is part of a larger study on multiple symptoms, QOL and self-efficacy in patients with COPD. The study was approved by the Lovisenberg Diaconale Hospital administration and the Norwegian Social Science Service, and it was recommended by the Regional Committee for Medical Research Ethics for Southern Norway. The protocol complied with the Declaration of Helsinki. Up to date, two papers have been published from the larger study (Borge, Wahl & Moum, 2010, 2011). Out of the 502 COPD patients on a registered list in the outpatient unit of a medium-large hospital in Norway, 387 persons met the following inclusion criteria: diagnosed with COPD in the medical record; able to read and write Norwegian; and older than 30 years. Between June 2007 and March 2008, these 387 persons were invited by mail to participate in this study.
Instruments Questionnaire booklet. Patients completed a questionnaire booklet containing questions about clinical and socio-demographic characteristics (i.e., gender, age, living status, education level, smoking status, number of diseases) and standardized measurements of breathlessness, physical
© 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd
health, mental health, global QOL and IP. They completed the booklet at home and brought it to the hospital by appointment. We considered an acceptable rate of missing answers in the questionnaires to be ≤ 20%. The following standardized questionnaires were used: Illness perception was measured with the Brief Illness Perception Questionnaire (BIPQ) (Broadbent et al., 2006). It contains nine questions grouped into items for illness identity, cause, consequences, timeline and cure. These items are: consequences (item 1); timeline (item 2); personal control (item 3); treatment control (item 4); identity (item 5); coherence (item 7); emotional representation (item 8); and casual (item 9). Items 3, 4, and 7 are reversed before interpretation. The scale scores range from 0–10, with higher scores indicating a more threatening view of the illness. The BIPQ has previously been used in persons with asthma. The questionnaire was validated with 6 weeks test–retest reliabilities for the items that ranged from 0.42 to 0.75 (Broadbent et al., 2006). The questionnaire has been translated into Norwegian. Breathlessness was measured with the breathlessness subscale from the Respiratory Quality of Life Questionnaire (RQLQ) (Stavem, Erikssen & Boe, 1999). The questionnaire was originally designed by Marks, Dunn and Woolcock (1992) and Marks, Burney, Premaratne, Simpson and Webb (1997) in Australia, and it has been used in asthma patients. It has been translated into Norwegian, and Stavem et al. (1999) have used it in Norwegian COPD patients. The questionnaire has 20 questions and four subscales with scores that range from 0–10: breathlessness, mood, concerns and social. Each item is measured on a 5-point scale: “not at all,” “mildly,” “moderately,” “severely” and “very severely.” Physical health and mental health conceptualized as health related quality of life were measured with the Short-Form 12 version 2 health survey (SF-12v2) (Ware, Kosinski & Keller, 1996). This questionnaire consists of 12 items that measure physical and mental health. Higher scores indicate better health. Previous studies have reported satisfactory results for the SF-12’s reliability and validity (Ware et al., 1996).The scores was calculated under a license scoring program (License number: QM006198). Global Quality of Life was measured by the Quality of Life Scale (QOLS) (Burckhardt, Woods, Schultz & Ziebarth, 1989). The QOLS contains 16 items that ask about overall satisfaction in domains of life such as health, work, leisure and independence. The items are scored on a 7-point Likert scale with a combined overall score ranging from 16–112. Higher scores indicate better overall perceived QOL. The questionnaire has been used in various patient populations in Norway, including patients with psoriasis (Wahl, Burckhardt, Wiklund & Hanestad, 1998) and cystic fibrosis (Wahl, Rustøen, Hanestad, Gjengedal & Moum, 2005). Physical tests. Forced expiratory volume in one second (FEV1) was measured with a spirometry test (VMax spirometry, SensorMedics, USA, with European standard measurement) according to the American Thoracic Society standard for lung function testing (Pellegrino, Viegi, Brusasco et al., 2005).
Statistical analysis Frequencies, means and standard deviations (SDs) were analyzed for the socio-demographic variables, clinical variables and self-reported data from the questionnaires. In order to analyze the relationship between demographic variables, social variables, clinical variables and the scores from the questionnaire for breathlessness, physical health, mental health, global QOL and IP, we used bivariate correlations (Person’s r) and hierarchical multiple linear regression analyses. We used IP dimensions (i.e., consequences, timeline, personal control, treatment control, identity, concern coherence, emotional representation) as dependent variables in separate multiple linear regression analyses using predicted lung function (FEV1%) and breathlessness as independents and controlling for age and gender. Further we used mental health score, physical health score and global QOL score as dependent variables in separate hierarchical multiple linear regression analyses controlling for step 1; age, gender, FEV1% and breathlessness and step 2; age, gender, FEV% and illness perception
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dimensions (separately), step 3; age, gender, FEV1%, breathlessness, and illness perception dimensions (separately). Standardized Beta (st. ß) is reported in the analysis. Possible mediator effects and the illness perception items were tested for significance using the Sobel test. Statistical significance was set at 5%, and all analyses were performed with IBM SPSS Statistics 20 (IBM, Armonk, NY).
Characteristics of dependent variables: IP, breathlessness, physical health, mental health and global QOL Table 2 presents the descriptive information for illness perception (BIPQ), breathlessness (RQLQ), physical health and mental health (SF-12), and global quality of life (QOLS). For further information see Table 2.
RESULTS The association between breathlessness and IP, controlling for demographic and clinical variables
Participants Out of the 168 people who agreed to participate, four persons were unable to complete the questionnaire, four did not return it and six withdrew their consent. Thus, 154 people (40% response rate) were included in the study.
Reliability of the questionnaires Cronbach’s alphas for the breathlessness subscale of the Respiratory Quality of Life Questionnaire and for the Global QOL of the Quality of Life Scale were both 0.87 in the present sample.
Characteristics of the sample: Socio-demographic and clinical variables
Table 2. Descriptors of breathlessness and score of questionnaires
Table 1 presents the socio-demographic and clinical variables. The mean age of the participants was 64.6 years, 51.3% were males, and 44.2% reported that they are still smokers. The mean predicted lung function was 59.1%, and the mean number of comorbidities was 1.9. For further information see Table 1. Table 1. Descriptors of demographic, social and clinical variables Variables
N (%)
Mean (SD)
Min–Max
Age (years) Gender: Male Female Education: Primary school (1) Vocational school (2) Secondary school (3) University < 4 years (4) University > 4 years (5) Living status: Living with someone Living alone Smoking: Yes No Number of co-morbidities Predicted lung function FEV1% Mild stage of COPD (FEV1% ≥ 80) Moderate stage of COPD (50% ≤ FEV1% < 80) Severe stage of COPD (30 ≤ FEV1% < 50) Very severe stage of COPD (FEV1% < 30)
154 154 79 75 152 35 27 47 28 15 154 77 77 154 68 86 154
(100) (100) (51.3) (48.7) (98.7) (22.7) (17.5) (30.5) (18.2) (9.7) (100) (50) (50) (100) (44.2) (55.8) (100)
64.6 (10.2)
36–87
154 (100)
59.1 (22.6)
2.7 (1.3)
1.9 (1.4)
The results of the bivariate analyses (Fig. 1) show that the IP items; consequences, identity, concern and emotional representation are significantly related to lower lung function (r = –0.21– –0.48, p < 0.01–0.001) and more symptoms of breathlessness (r = 0.44–0.67, p < 0.01–0.001). Further, a lower lung function is significantly related to higher scores of the IP item timeline (r = –0.19, p < 0.05, Fig. 1). In the regression analyses with IP items as the dependent variables, there were no significant relationships between IP scores and the demographic variables (Table 3). However, a lower predicted lung function is significantly associated with a higher IP
Variables
N
Mean (SD)
Range
Score for each Illness Perception item: 1. How much does your illness affect your life?
153
5.9 (2.6)
1–10
2. How long do you think your illness will continue?
150
9.3 (1.7)
1–10
3. How much control do you feel you have over your illness?
153
5.6 (2.5)
1–10
4. How much do you think your treatment can help your illness?
146
4.5 (2.6)
1–10
5. How much do you experience symptoms from your illness?
153
5.9 (2.2)
1–10
6. How concerned are you about your illness?
153
5.6 (2.9)
1–10
7. How well do you feel you understand your illness?
153
4.0 (2.5)
1–10
8. How much does your illness affect you emotionally? (e.g., does it make you angry, scared, upset or depressed?
153
Breathlessness (Possible score from 0–10) Physical health (SF-12, PCS) (Possible score from 0–100) Mental health (SF-12, MCS) (Possible score from 0–100) Global quality of life (Possible score from 16–112)
153
2.4 (2.1)
144
32.4 (10.8)
4.6–56.8
154
47 (12.3)
13.5–72.6
154
80.3 (14.1)
35–110
1–5
0–7 17–124
28 (18) 72 (46.8) 39 (25.3) 15 (9.7)
© 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd
48 (2.8)
1–10
0–7.5
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r= - 0.43*** FEV1% r=0.67 *** Breathlessness
r= - 0.19* FEV1 %
r= - 0.62*** Physical health r= - 0.26** Mental health r= - 0.38*** Global quality of life
Consequences Timeline
Personal control
Treatment control r= - 0.48*** FEV1% r=0.62*** Breathlessness
r= - 0.24*** FEV1% r=0.44** Breathlessness
r= - 0.50*** Physical health r= - 0.30** Mental health r= - 0.31**** Global quality of life
Identity
r= - 0.31*** Physical health r= - 0.19*Mental health r= - 0.31** Global quality of life
Concern
Coherence
r= - 0.21** FEV1% r=0.45*** Breathlessness
r= - 0.21*Global quality of life
Emotional
r= - 0.20** Physical health r= - 0.55*** Mental health r= - 0.47***Global quality of life
representation
Notes: Breathlessness: higher score= more problems with breathlessness, IP score (consequences, timeline, personal control treatment control identity, concern, coherence, emotional representation) higher score = higher perceived threats from illness, Physical health and Mental health: higher score = fewer health problems, Global quality of life: higher score = better quality of life. * p < 0.05, ** p < 0.01, *** p < 0.001.
Fig. 1. Bivariate relationship between lung function (FEV1%), breathlessness, brief illness perception questionnaire, physical health, mental health and global quality of life. Pearson’s r.
score with regard to the items consequences (st. b = –0.19, p < 0.05) and identity (st. b = –0.28, p < 0.001). More symptoms of breathlessness are associated with a higher IP score on the items consequences (st. b = 0.62, p < 0.001), identity (st. b = 0.51, p < 0.001), concern (st. b = 0.40, p < 0.001) and emotional representation (st. b = 0.37, p < 0.001). The adjusted variances of the significantly associated variables explain 50% for consequences, 45% for identity, 19% for concern and 21% for emotional representation. The Sobel test shows that predicted lung function becomes significantly lower ( p < 0.001) or vanish as a significant predictor when breathlessness is entered in the equations (see Fig. 1) in which the dependent variables are consequences, identity, concern and emotional representation, indicating that breathlessness acted as mediator between predicted lung function and illness perception in these cases (Table 3).
The associations between IP and mental health, physical health and global QOL, controlling for demographic, clinical variables and breathlessness The results of the bivariate analyses (Fig. 1) show that higher scores on IP items; consequences, identity, concern and emotional representation are significantly related to impaired physical health (r = –0.20 – –0.62, p < 0.05–0.001), mental health (r = –0.19 – –0.55, p < 0.05–0.01) and global QOL (r = –0.31 – –0.47, p < 0.01–0.001). In addition, higher levels on IP coherence are significantly related to impaired global QOL (r = –0.21, p < 0.05). Table 4, shows the multiple regression analysis between IP items, breathlessness, FEV1% and physical health, mental health and global QOL, controlling for age and gender. More breathlessness is significantly related to impaired physical health (st. b = –0.52, p < 0.001), mental health (st. b = –0.32, p < 0.01) and global QOL (st. b = –0.39, p < 0.001).
Table 3. Predicting illness perception by breathlessness and predicted lung function (FEV1%). Multiple linear regressions with controls for age and gender. Standardized betas and explained variance
Consequences (BIPQ 1)b ᵇ St ß FEV1% Breathlessnessa Adjusted R²
0.19* 0.62*** 0.50
Timeline (BIPQ 2)b ᵇ St ß 0.18 0.05 0.04
Personal control (BIPQ 3)bᵇ St ß 0.03 0.00 0.03
Treatment control (BIPQ 4)b ᵇ St ß 0.14 0.05 0.00
Identity (BIPQ 5)b ᵇ St ß
Concern (BIPQ 6)b ᵇ St ß
0.28*** 0.51*** 0.45
0.12 0.40*** 0.19
Coherence (BIPQ 7)b ᵇ St ß 0.10 0.09 0.01
Emotional representation (BIPQ 8)b ᵇ St ß 0.15 0.37*** 0.21
Notes: a higher score = more problems with breathlessness,ᵇb higher score = higher perceived threats from illness, *p < 0.05, ***p < 0.001. Age and gender showed no significant effects in any of the equations (i.e., when predicted lung function and breathlessness was controlled). © 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd
© 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd b
–0.15 0.07
–0.04 0.05
–0.27** 0.11
–0.52*** 0.25
0.05 0.03
–0.11 0.06
–0.10 0.07
–0.63*** 0.37
Step 2
–0.22* –0.49*** 0.39 –0.50*** –0.08 0.27 –0.52*** –0.11 0.28 –0.51*** 0.03 0.25 –0.36*** –0.33** 0.33 –0.48*** –0.10 0.28 –0.53*** –0.07 0.27 –0.53*** –0.04 0.27
Step 3 –0.32** 0.13
Step 1
–0.53*** 0.30
–0.13 0.07
–0.13 0.07
–0.30** 0.12
–0.01 0.05
0.03 0.05
0.13 0.07
–0.25** 0.10
Step 2
Mental healthc ᶜ
d
–0.39*** 0.16
Step 1
–0.44*** 0.22
–0.21* 0.08
–0.24** 0.09
–0.33** 0.12
–0.13 0.06
0.02 0.04
–0.09 0.06
–0.41*** 0.17
Step 2
Global quality of lifed ᵈ
higher score = better quality of life,
–0.28* –0.08 0.13 –0.32*** 0.14 0.15 –0.32*** 0.03 0.13 –0.33*** –0.02 0.14 –0.24* –0.17 0.15 –0.31** –0.03 0.13 –0.34*** –0.15 0.15 –0.15 –0.48*** 0.31
Step 3
higher score = higher perceived threats from illness, ᶜ c higher score = fewer health problems, ᵈ
–0.52*** 0.28
Breathlessnessa Adjusted R² Breathlessnessa Consequences (BIPQ-1)b ᵇ Adjusted R² Breathlessnessa Timeline (BIPQ-2)b ᵇ Adjusted R² Breathlessnessa Personal control (BIPQ-3)b ᵇ Adjusted R² Breathlessnessa Treatment control (BIPQ-4)b ᵇ Adjusted R² Breathlessnessa Identity (BPIQ-5)b ᵇ Adjusted R² Breathlessnessa Concern (BIPQ-6)b ᵇ Adjusted R² Breathlessnessa Coherence (BIPQ-7)b ᵇ Adjusted R² Breathlessnessa Emotional representation (BIPQ-8)b ᵇ Adjusted R²
Independent variable breathlessness: Independent variable breathlessness and IP:
Notes: a higher score = more problems with breathlessness,ᵇ *p < 0.05, **p < 0.01, ***p < 0.001.
Step 1
Standardized betas
Variables↓
Physical healthc ᶜ
–0.21* –0.28** 0.20 –0.36*** –0.07 0.16 –0.39*** 0.02 0.16 –0.38*** –0.15 0.18 –0.31** –0.16 0.17 –0.34*** –0.14 0.18 –0.41*** –0.22* 0.21 –0.26** –0.35*** 0.26
Step 3
Table 4. Direct and indirect effects of breathlessness and illness perception on dependent variables. Multiple linear regression analyses with standardized betas and explained variance. All coefficients controlled for age, gender and FEV 1%
460 C. R. Borge et al. Scand J Psychol 55 (2014)
Scand J Psychol 55 (2014)
The explained variance is 28% for physical health, 13% for mental health and 16% for global QOL (step 1, Table 4). In the equations, higher scores on the IP items; consequences (st. b = –0.63, p < 0.001), identity (st. b = –0.52 p < 0.001) and concern (st. b = –0.27, p < 0.01) are significantly related to impaired physical health (step 2, Table 4). The adjusted variances of the significantly associated variables explain 37% for consequences, 25% for identity and 11% for concern in physical health. Further higher scores on the IP items; consequences (st. b = –0.25, p < 0.01), identity (st. b = –0.30, p < 0.01) and emotional representation (st. b = –0.53, p < 0.001) are significantly related to impaired mental health (step 2, Table 4). The adjusted variances of the significantly associated variables explain 10% for consequences, 12% for identity and 30% for emotional representation in mental health. Finally, impaired global QOL is associated with higher IP scores on the items consequences (st. b = –0.41, p < 0.001), identity (st. b = –0.33, p < 0.01), concern (st. b = –0.24, p < 0.01), coherence (st. b = –0.21, p < 0.05) and emotional representation (st. b = –0.44, p < 0.001) (step 2, Table 4). The adjusted variances of the significantly associated variables explain 17% for consequences, 12% for identity, 9% for concern, 8% for coherence and 22% for emotional representation in global QOL. After entering breathlessness and IP items in step 3 the st. b for breathlessness was significantly reduced in the equations (sobel test) for (1) consequences and physical health, (2) identity and physical health, (3) emotional representation and mental health, and (4) consequences and global QOL compared to step 1, indicating that the said IP items acted as mediators in the those relationships (Table 4). In the other 19 equations we found no mediator effect of the IP items.
DISCUSSION Our findings support the assumptions in the CSM and the expected pattern of breathlessness being associated with certain dimensions of IP (greater perceived threat from the illness), and several dimensions of IP being associated with poorer health and QOL. In this study we found that people with COPD who experienced more breathlessness also perceived more consequences, higher identity of symptoms, were more concerned and reported a higher emotional representation of the disease. The explained variance in IP was highest for those who experienced more consequences (50%) from their disease and identified more symptoms (45%) from their disease. This indicates that the experience of breathlessness has an important impact on how people with COPD think about their disease. They may experience consequences in various ways such as pulmonary infections, coughing and sputum (Hill, Goldstein, Guyatt et al., 2010). A person might not know that he/she has COPD because shortness of breath comes on only gradually. It is well known that people with COPD often wait to contact their doctor until they start becoming aware of increased breathlessness, and by then their pulmonary function has already become chronically debilitated (GOLD, 2013; Hill et al., 2010). In our study, we found bivari© 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd
Illness perception in people with COPD 461 ate associations between decreased lung function and higher IP of the dimensions consequences, timeline, identity, concern and emotional representation. Further breathlessness emerged as a mediator in the relationship between predicted lung function and the IP dimensions consequences, identity, concern and emotional representation. Our results are interesting, since in previous research we have only found evidence of a bivariate association between the dimension emotional representation (Howard et al., 2009) and consequences with low predicted lung function (Howard et al., 2009; Fischer et al., 2010). As explained by the CSM, decreased pulmonary function may lead to fear of breathlessness, which in turn may impact on how COPD patients focus on the consequences of the disease and fear that the disease will last for a long time and that more symptoms are expected which in its turn will lead to greater concern and representation of emotional distress. The results from our study show that those who report poor physical health also experienced more consequences, identified more symptoms, and were more concerned about their disease. Hartman et al. (2013) found similar results; namely, that those being less physically active also experienced more consequences and were more concerned about their disease. Scharloo et al. (2007) also found a relationship with the dimension consequences, but in addition with timeline which surprisingly we did not find. Our results could be explained by the fact that a majority of our patients had a moderate stage of disease (46.8%). On this background they might still be rather optimistic about their disease, entertaining hopes of getting better (Philip, Gold, Brand, Douglass, Miller & Sundararajan, 2012). Mental health scores were negatively affected by patients who perceived more consequences from their disease, identified more symptoms and reported higher emotional representation. Similar results are reported by Scharloo et al. (2007) who find an association between high IP scores (using the subscales “illness identity,” “emotional representations” and “causal attributions”) and increased mental health problems in COPD patients. With respect to breathlessness, we found a significant relationship to poorer mental health, which is consistent with research by Moy et al. (2009), who reported that breathlessness in COPD is significantly related to more mental health problems. The “global quality of life” concept used in this study (Burckhardt et al., 1989) refers to how happy people are with respect to their economic situation, work and relationships with friends and family. In our study, we found that several of the IP dimensions were related to reduced global QOL (i.e., consequences, identity, concern, coherence, emotional representation). We have not found any other studies that have examined how global QOL is related to IP in COPD patients. However, it seems reasonable that the more one perceives COPD as a threat, the worse one’s global QOL will be. The effect of breathlessness became significantly weaker only in few of the equations in which IP was introduced as an additional independent, that is, the effects on physical health (reduced by consequences, identity), mental health (reduced by emotional representation) and global QOL (reduced by consequences and global QOL) indicating that IP acted as a mediating
462 C. R. Borge et al. factor in the said associations. Thus most of the IP items show direct relationships with QOL and these relationships are not confounded by breathlessness nor do they mediate the impact of breathlessness which retains its direct effects in most cases. Given the results of this study, it may be worthwhile to focus on IP in COPD health care interventions such as rehabilitation and patient education as a focus like this could help to reduce the impact of symptoms. An example of such an intervention was reported by Broadbent, Ellis, Thomas, Gamble and Petrie (2009), who showed that a tailored IP intervention helps myocardial infarction patients get back to work and also gain a better understanding of their condition. Furthermore, teaching patients to be physically active could reduce fear, which is part of the reasoning behind physical training, mental assessment and pulmonary rehabilitation programs in COPD treatment (Troosters, Casaburi, Gosselink & Decramer, 2005). However, it may be necessary to develop broader IP interventions, including how to motivate patients to change their illness perceptions, especially with respect to evaluating their disease as less threatening. For example, such an intervention could be included in regular conversations with patients and their spouses before and after hospitalizations, or as a regular component of self-management pulmonary rehabilitation programs. Teaching COPD patients strategies to control their symptoms of breathlessness for example by means of breathing control exercises might also be a strategy to influence illness perception in patients with COPD.
STRENGTHS AND LIMITATIONS There are several limitations to this study. First, the crosssectional design does not allow us to make causal inferences about the relationships reported here. Second, the response rate was rather low (40%), partly because the inclusion criteria required participants to speak and write Norwegian, and partly because COPD patients at all stages of the disease were allowed to participate. The first requirement may have limited participation because the outpatient list used for this study was for an area of Norway where there are many minority speaking people, and the second criterion meant that patients in more advanced stages of COPD may not have had the energy to participate. We used an early version of the Norwegian BIPQ that had a scale from 1–10 and not 0–10. This may have resulted in a higher IP. However, separate analyses show that the patients in our study scoring 1 were of low frequency with a mean of 5%. On this background we believe that our result might not have been influenced much by the missing value 0 in the scale.
CONCLUSIONS We found that patients with COPD who experience a high degree of breathlessness also perceive COPD to be more threatening. For most IP domains higher scores were associated with more physical health problems, mental health problems and a lower global QOL. Our data also indicated that only few of the IP items act as mediators in the relationship between breathlessness and physical/mental health and global QOL. © 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd
Scand J Psychol 55 (2014)
Our results suggest the possibilities of interventions aiming to help people with COPD to manage their symptoms, be more realistic about their disease and understand its consequences. Tailoring IP interventions along these lines might help COPD patients restructure their perceptions of COPD, which, in turn, even could help to reduce symptoms of breathlessness and increase physical activity and QOL. CB and AW were responsible for the study conception, design and data collection. CB, AW and TM performed the analysis. All authors were responsible for writing and revisions of the manuscript. There are no conflicts of interest in this study.
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