COPD, 00:1–7, 2014 ISSN: 1541-2555 print / 1541-2563 online Copyright © Informa Healthcare USA, Inc. DOI: 10.3109/15412555.2014.898034
ORIGINAL RESEARCH
COPD Assessment Test: A Simple Tool to Evaluate Disease Severity and Response to Treatment Maria Papaioannou,1 Georgia Pitsiou,2 Katerina Manika,1 Paschalina Kontou,3 Pavlos Zarogoulidis,1 Lazaros Sichletidis,1 and Ioannis P. Kioumis1
COPD Downloaded from informahealthcare.com by University of Laval on 06/05/14 For personal use only.
1
Department of Pneumonology, Aristotle University of Thessaloniki, G.H. “G. Papanikolaou,” Exohi, Thessaloniki, Greece
2
Respiratory Intensive Care Unit, Aristotle University of Thessaloniki, G.H. “G. Papanikolaou,” Exohi, Thessaloniki, Greece
3
1st Intensive Care Unit, G.H. “G. Papanikolaou”, Exohi, Thessaloniki, Greece
Abstract The COPD assessment test (CAT) is a short questionnaire designed to assess the impairment in health status of COPD patients. We aimed to determine the change of the CAT in COPD patients after 1 year of treatment and test the association between the score and clinical and lung function variables. Methods A cohort of 111 newly diagnosed COPD patients in primary care was evaluated at baseline and one year after the implementation of the recommended treatment according to the Global Initiative for the management of COPD (GOLD). Results Most of the patients (82%) were diagnosed with mild to moderate airflow limitation (mean FEV1 72 ± 21.5% predicted) and the CAT score increased in proportion with the GOLD stage of severity. The CAT significantly correlated with the number of exacerbations, visits to general practitioners and days of hospitalization both at the beginning and at 1 year follow-up. A strong negative correlation between the CAT score and FEV1 predicted was also observed. The CAT was responsive to the application of treatment with a significant improvement in the mean score (95% confidence interval) following 12 months of treatment by –2.4 (–2.9, –1.9) despite the small decline in lung function indices. The number of exacerbations in the preceding year and FEV1 were independent predictors of the CAT score in the general linear model. Conclusion The CAT questionnaire may serve as a simple, measurable tool complementary to spirometry in the assessment of severity and of response to treatment in unselected COPD patients in primary care.
Abbreviations CAT GOLD SGRQ GPs ICS/LABA
COPD assessment test Global Initiative for COPD St George’s Respiratory Questionnaire general practitioners inhaled corticosteroids/long-acting β2 agonists
Introduction Keywords: disease management, exacerbation, health status, lung function; primary care Correspondence to: Ioannis P. Kioumis, M.D., Ph.D., Associate Professor of Pneumonology-Infectious Diseases, Aristotle University of Thessaloniki, Department of Pneumonology, Gen. Hospital “G. Papanikolaou,” Exohi 57010, Thessaloniki, Greece, phone: 0030 2313 307974, fax: 0030 2310 358477, email: [email protected]
The COPD assessment test (CAT) is a short, patient-completed questionnaire designed to provide a score that indicates the impact of the disease on health status of COPD patients (1). CAT development has involved well-accepted methodologies used to develop psychometric tools (1). Subsequent item reduction and validation studies resulted in the final 8-item CAT questionnaire with good sensitivity and reliability (1,2). The eight questions forming the CAT cover the most burdensome symptoms of COPD such as breathlessness and limitations in daily activities. The design of the test aims to improve the communication between COPD patients and healthcare 1
COPD Downloaded from informahealthcare.com by University of Laval on 06/05/14 For personal use only.
2
Papaioannou et al.
professionals, thus enabling a common understanding of the disease’s severity and impact (2). Interestingly, it has been demonstrated that it is possible to relate CAT scores to clinical scenarios descriptive of impaired health status in COPD, providing users of the CAT with a more rounded understanding of the effects of COPD associated with different CAT scores (3). The questionnaire exhibits high reproducibility and is independent of various languages, as well (4,5). When compared with other more complex health status questionnaires, such as St. George’s Respiratory Questionnaire (SGRQ) and clinical COPD Questionnaire, the CAT showed similar psychometric properties (2,6). Although SGRQ reflects the COPD health status very well, it is rather complicated, time consuming and scores can only be calculated by a computer-based scoring system (6). On the other hand, the CAT is much shorter and easier to use, and can be completed within a few minutes at most (1). The high correlation between SGRQ and CAT is remarkable, suggesting that the CAT provides a reliable measure of the impact of COPD on a patient’s health status (2,6). Recent studies also indicate that the CAT is sensitive to changes in health status associated with recovery from exacerbations (7), and is immediately responsive to pulmonary rehabilitation, not only in COPD, but also in unselected chronic respiratory disease patients (8,9). We hypothesized that CAT score, owing to its good discriminative properties, would be sensitive to detect treatment effects in a cohort of COPD patients. Accordingly, the aim of the present study is: (i) to establish the association between clinical variables and the CAT score in a cohort of first diagnosed COPD patients in primary care and (ii) to determine the change of CAT score and associate variables following 1 year of treatment with application of current GOLD guidelines in routine clinical practice.
Patients and methods Details of the initial study design and entry requirements have been published previously and are summarized here (10). Twenty-five general practitioners (GPs) in Northern Greece participated in the study. The first 50 patients aged >40 years, who visited each GP for any reason during the period for 1st March 2009 to 31 May 2009 and fulfilled the entry criteria, were included in the study. All participants completed the IPAG questionnaire (11) and underwent spirometry with the handheld PiKo-6® flow meter, both of which were used as screening tools for the diagnosis of COPD. Exclusion criteria were previous medically confirmed diagnosis of respiratory diseases, previous use of inhaler medication and uncontrolled cardiac disease. Guided by a respiratory physician who visited the GPs, all subjects performed spirometry (Vitalograph Ltd, Buckingham, UK) according to American Thoracic Society/ European Respiratory Society (ATS/ERS) guidelines (12). Postbronchodilator forced expiratory volume in 1 second
(FEV1), forced vital capacity (FVC) and FEV1/FVC were recorded. Patients with significant (> 12%) acute bronchodilator reversibility were excluded from the present study. COPD diagnosis was based on physicians’ clinical evaluation and was confirmed by post-bronchodilator spirometry on stable condition according to Global Initiative for Obstructive Lung Disease (GOLD) guidelines (13). Then, 111 newly diagnosed COPD patients were finally enrolled in the present study. The Medical Ethics Committee of the G. Papanikolaou Hospital, Thessaloniki, Greece approved the study protocol. The patients were categorized in GOLD stages according to the severity of airflow limitation (post-bronchodilator FEV1 % predicted > 80% for stage I, 50–80% for stage II, 30–50% for stage III and < 30% for stage IV). Pharmacological treatment was assigned by the GPs according to the GOLD stage. In particular, short acting bronchodilators (salbutamol 200 mcg prn) were recommended as “rescue” relief therapy for GOLD stage I patients, long-acting anticholinergic or long-acting β2 agonists (tiotropium 18 mcg od or formoterol 12 mcg bid) for GOLD stage II patients and finally a combination of inhaled corticosteroids with long-acting β2 agonists (ICS/LABA) or/and long-acting anticholinergic (budesonide/formoterol 320/9 mcg bid or/and tiotropium 18 mcg od) for GOLD severity stage III and IV patients. Compliance to treatment was monitored by the GPs during the next 12 months at regular followup visits every 3 months. All subjects performed a second spirometry, conducted by the respiratory physicians, in a follow-up visit after 12 months of treatment. All participants completed an 8-item CAT questionnaire both at the time of diagnosis (baseline-CAT1) as well as after one year of treatment (end of study-CAT2). The history of exacerbations, hospitalization and visit to GPs related to COPD during the previous 12 months was recorded at baseline and 1 year after the implementation of the recommended treatment. An exacerbation was defined as a worsening of symptoms that required oral corticosteroids and/or antibiotics and/or hospitalization. The presence of cardiovascular disease in general, as well as the presence of systemic hypertension, coronary artery disease, congestive heart failure, arrhythmias or stroke, was specifically recorded.
CAT questionnaire The patients in this study completed the CAT questionnaire that was validated by Jones (1). The CAT consists of eight items, each formatted as a semantic 6-point differential scale, making the tool easy for patients to complete. The items are related to cough and phlegm, chest tightness, breathlessness going up hills/stairs, activity limitations at home, confidence leaving home, sleep and energy. Each item is scored from 0 to 5, giving a total score range from 0 to 40 and providing a reliable measure of the impact of COPD on a patient’s health status. CAT scores are categorized into severity bands, as described in the CAT users guide (http://www.catestonline.org): Low Impact (CAT Copyright © 2014 Informa Healthcare USA, Inc
COPD Assessment Test in primary care
Table 1. Demographic and clinical characteristics of patients with COPD (N = 111) GOLD stage Characteristic
I
II
III
IV
Reported population
Subjects No.
40
52
17
2
111
71.1 ± 8.8
71.1 ± 8.7
70.7 ± 8.9
69.7 ± 10.6
71.1 ± 8.7
0.546
Females
4
8
5
0
17
0.280
Males
36
44
12
2
94
Smoking status Smokers Non-smokers Former smokers
13 3 20
14 7 23
5 2 5
0 0 2
38 21 52
Smoking, pack-years
44.5 ± 38.8
44.2 ± 38.4
45.6 ± 39.8
53.6 ± 35.8
44.4 ± 38.6
0.250
2.36 ± 0.49 a
1.85 ± 0.47 b
1.07 ± 0.31 c
0.68 ± 0.18 c
1.89 ± 0.64
< 0.001
3.49 ± 0.67
2.77 ± 0.66
1.83 ± 0.52
1.78 ± 0.60
2.87 ± 0,86
0.776
0.68 ± 0.03 a
0.67 ± 0.04 a
0.59 ± 0.07 b
0.39 ± 0.03 c
0.65 ± 0.61
< 0.001
Age, years
FEV1, L/sec FVC, L FEV1/FVC COPD Downloaded from informahealthcare.com by University of Laval on 06/05/14 For personal use only.
p value
0.182
Values are expressed as mean ± SD. All spirometric data refer to values after bronchodilation. FEV1: forced expiratory volume in 1 second; FVC: forced vital capacity. Values followed by different letters within lines differ significantly.
score 1 to 10), Medium Impact (11 to 20), High Impact (21 to 30), and Very High Impact (31 to 40) (14). The questionnaire was accessed via www.CATestonline.org and was translated into the Greek language.
Statistical analysis The paired samples t-test was used to test pre- versus post-treatment differences between continuous measurements, while the chi-square test was used for the comparison of proportions. One-way analysis of variance (ANOVA) was employed in order to check differences of continuous measurements among GOLD stages, and the Tukey-Kramer HSD test was used as post-hoc. The Pearson correlation coefficient was used for the assessment of linear relationships between continuous variables. The General Linear Model was used for the assessment of the dependence between the CAT score and FEV1, adjusting for the presence of exacerbations, while binary logistic regression was used to model the probability of exacerbation based on CAT scores. Any p-values less than 0.05 were considered statistically significant. The statistical package SPSS version 17.0 (SPSS Inc., Chicago, IL) and JMP 8.0 (SAS Inst., Cary, NC) were used for data analysis.
Results Of the 1,250 subjects examined (50 subjects × 25 GPs), 172 refused to participate in the second phase of the study (spirometry) or did not meet the ATS/ERS criteria for spirometry. Thus, data on 1,078 subjects (57.1% males, mean age 65.3 ± 11.4 years) were collected and analyzed. The percentage of smokers was 48.4% (38 ± 29 pack-years). We diagnosed 111 (10.3%) patients with COPD who were enrolled in the current extension study. Five patients were withdrawn due to lack of compliance to treatment (3/5) and due to serious adverse event www.copdjournal.com
unrelated to treatment (death 1-stroke 1). In the subgroup of smokers the prevalence of COPD was 17.2% (90/522). The clinical characteristics of COPD patients are summarized in Table 1. The majority of COPD patients were males with a mean age of 71 years, mean smoking history of 44 pack-years and mean FEV1 of 1.89 L (72 ± 21.5% predicted). Most of them (92/111, 82%) were classified in GOLD stages I and II. In one year follow-up, mean FEV1 decreased by 0.06 (95% confidence interval: −0.08, −0.03) and FVC by 0.06 (95% CI: −0.09, −0.02). Following 12 months of treatment, a substantial decrease in the number of exacerbations was also observed from the patients’ medical records (paired t-test, t105 = 4.83, p < 0.001). A proportional decrease was found in the number of visits to GPs (t105 = 7.52, p < 0.001). No difference in the number of hospitalizations (t105 = −0.38, p = 0.71) and the days of hospitalizations (t105 = 0.96, p = 0.34) was noted (Table 2).
CAT scores and COPD severity There was a significant improvement in the mean CAT score following 12 months of treatment by −2.4 (95% CI: −2.9, −1.9); p < 0.001. CAT score increased along with severity according to the GOLD stage, demonstrating impairment in health status of the patients across all stages. This result was found both at baseline (one-way ANOVA, F3,107 = 59.17, p < 0.001) and at the end of the study (F3,102 = 30.98, p < 0.001) (Table 3). A significant correlation between FEV1 and total CAT score was detected at baseline (Pearson correlation, r = −0.583, p < 0.001) and at the end of study as well (r = −0.523, p < 0.001). Association between CAT scores and exacerbations Based on binary logistic regression modeling, we sought to assess if exacerbations lead to poorer health outcomes as measured by the CAT and whether the CAT score
3
4
Papaioannou et al.
COPD Downloaded from informahealthcare.com by University of Laval on 06/05/14 For personal use only.
Table 2. Change of the CAT score, the clinical and lung function parameters after 12 months of treatment
CAT FEV1, L/sec FEV1% pred FVC, L FEV1/FVC Exacerbations Yes No No. of Exacerbations Hospitalizations Yes No No. of hospitalizations Days of hospitalizations Visits to GPs Yes No No. of visits to GPs
Pre-treatment
Post-treatment
p value
10.8 ± 6 1.89 ± 0.64 72 ± 22 2.87 ± 0.86 0.65 ± 0.06
8.4 ± 4.5 1.83 ± 0.61 67 ± 24 2.81 ± 0.83 0.65 ± 0.05
ORIGINAL RESEARCH
COPD Assessment Test: A Simple Tool to Evaluate Disease Severity and Response to Treatment Maria Papaioannou,1 Georgia Pitsiou,2 Katerina Manika,1 Paschalina Kontou,3 Pavlos Zarogoulidis,1 Lazaros Sichletidis,1 and Ioannis P. Kioumis1
COPD Downloaded from informahealthcare.com by University of Laval on 06/05/14 For personal use only.
1
Department of Pneumonology, Aristotle University of Thessaloniki, G.H. “G. Papanikolaou,” Exohi, Thessaloniki, Greece
2
Respiratory Intensive Care Unit, Aristotle University of Thessaloniki, G.H. “G. Papanikolaou,” Exohi, Thessaloniki, Greece
3
1st Intensive Care Unit, G.H. “G. Papanikolaou”, Exohi, Thessaloniki, Greece
Abstract The COPD assessment test (CAT) is a short questionnaire designed to assess the impairment in health status of COPD patients. We aimed to determine the change of the CAT in COPD patients after 1 year of treatment and test the association between the score and clinical and lung function variables. Methods A cohort of 111 newly diagnosed COPD patients in primary care was evaluated at baseline and one year after the implementation of the recommended treatment according to the Global Initiative for the management of COPD (GOLD). Results Most of the patients (82%) were diagnosed with mild to moderate airflow limitation (mean FEV1 72 ± 21.5% predicted) and the CAT score increased in proportion with the GOLD stage of severity. The CAT significantly correlated with the number of exacerbations, visits to general practitioners and days of hospitalization both at the beginning and at 1 year follow-up. A strong negative correlation between the CAT score and FEV1 predicted was also observed. The CAT was responsive to the application of treatment with a significant improvement in the mean score (95% confidence interval) following 12 months of treatment by –2.4 (–2.9, –1.9) despite the small decline in lung function indices. The number of exacerbations in the preceding year and FEV1 were independent predictors of the CAT score in the general linear model. Conclusion The CAT questionnaire may serve as a simple, measurable tool complementary to spirometry in the assessment of severity and of response to treatment in unselected COPD patients in primary care.
Abbreviations CAT GOLD SGRQ GPs ICS/LABA
COPD assessment test Global Initiative for COPD St George’s Respiratory Questionnaire general practitioners inhaled corticosteroids/long-acting β2 agonists
Introduction Keywords: disease management, exacerbation, health status, lung function; primary care Correspondence to: Ioannis P. Kioumis, M.D., Ph.D., Associate Professor of Pneumonology-Infectious Diseases, Aristotle University of Thessaloniki, Department of Pneumonology, Gen. Hospital “G. Papanikolaou,” Exohi 57010, Thessaloniki, Greece, phone: 0030 2313 307974, fax: 0030 2310 358477, email: [email protected]
The COPD assessment test (CAT) is a short, patient-completed questionnaire designed to provide a score that indicates the impact of the disease on health status of COPD patients (1). CAT development has involved well-accepted methodologies used to develop psychometric tools (1). Subsequent item reduction and validation studies resulted in the final 8-item CAT questionnaire with good sensitivity and reliability (1,2). The eight questions forming the CAT cover the most burdensome symptoms of COPD such as breathlessness and limitations in daily activities. The design of the test aims to improve the communication between COPD patients and healthcare 1
COPD Downloaded from informahealthcare.com by University of Laval on 06/05/14 For personal use only.
2
Papaioannou et al.
professionals, thus enabling a common understanding of the disease’s severity and impact (2). Interestingly, it has been demonstrated that it is possible to relate CAT scores to clinical scenarios descriptive of impaired health status in COPD, providing users of the CAT with a more rounded understanding of the effects of COPD associated with different CAT scores (3). The questionnaire exhibits high reproducibility and is independent of various languages, as well (4,5). When compared with other more complex health status questionnaires, such as St. George’s Respiratory Questionnaire (SGRQ) and clinical COPD Questionnaire, the CAT showed similar psychometric properties (2,6). Although SGRQ reflects the COPD health status very well, it is rather complicated, time consuming and scores can only be calculated by a computer-based scoring system (6). On the other hand, the CAT is much shorter and easier to use, and can be completed within a few minutes at most (1). The high correlation between SGRQ and CAT is remarkable, suggesting that the CAT provides a reliable measure of the impact of COPD on a patient’s health status (2,6). Recent studies also indicate that the CAT is sensitive to changes in health status associated with recovery from exacerbations (7), and is immediately responsive to pulmonary rehabilitation, not only in COPD, but also in unselected chronic respiratory disease patients (8,9). We hypothesized that CAT score, owing to its good discriminative properties, would be sensitive to detect treatment effects in a cohort of COPD patients. Accordingly, the aim of the present study is: (i) to establish the association between clinical variables and the CAT score in a cohort of first diagnosed COPD patients in primary care and (ii) to determine the change of CAT score and associate variables following 1 year of treatment with application of current GOLD guidelines in routine clinical practice.
Patients and methods Details of the initial study design and entry requirements have been published previously and are summarized here (10). Twenty-five general practitioners (GPs) in Northern Greece participated in the study. The first 50 patients aged >40 years, who visited each GP for any reason during the period for 1st March 2009 to 31 May 2009 and fulfilled the entry criteria, were included in the study. All participants completed the IPAG questionnaire (11) and underwent spirometry with the handheld PiKo-6® flow meter, both of which were used as screening tools for the diagnosis of COPD. Exclusion criteria were previous medically confirmed diagnosis of respiratory diseases, previous use of inhaler medication and uncontrolled cardiac disease. Guided by a respiratory physician who visited the GPs, all subjects performed spirometry (Vitalograph Ltd, Buckingham, UK) according to American Thoracic Society/ European Respiratory Society (ATS/ERS) guidelines (12). Postbronchodilator forced expiratory volume in 1 second
(FEV1), forced vital capacity (FVC) and FEV1/FVC were recorded. Patients with significant (> 12%) acute bronchodilator reversibility were excluded from the present study. COPD diagnosis was based on physicians’ clinical evaluation and was confirmed by post-bronchodilator spirometry on stable condition according to Global Initiative for Obstructive Lung Disease (GOLD) guidelines (13). Then, 111 newly diagnosed COPD patients were finally enrolled in the present study. The Medical Ethics Committee of the G. Papanikolaou Hospital, Thessaloniki, Greece approved the study protocol. The patients were categorized in GOLD stages according to the severity of airflow limitation (post-bronchodilator FEV1 % predicted > 80% for stage I, 50–80% for stage II, 30–50% for stage III and < 30% for stage IV). Pharmacological treatment was assigned by the GPs according to the GOLD stage. In particular, short acting bronchodilators (salbutamol 200 mcg prn) were recommended as “rescue” relief therapy for GOLD stage I patients, long-acting anticholinergic or long-acting β2 agonists (tiotropium 18 mcg od or formoterol 12 mcg bid) for GOLD stage II patients and finally a combination of inhaled corticosteroids with long-acting β2 agonists (ICS/LABA) or/and long-acting anticholinergic (budesonide/formoterol 320/9 mcg bid or/and tiotropium 18 mcg od) for GOLD severity stage III and IV patients. Compliance to treatment was monitored by the GPs during the next 12 months at regular followup visits every 3 months. All subjects performed a second spirometry, conducted by the respiratory physicians, in a follow-up visit after 12 months of treatment. All participants completed an 8-item CAT questionnaire both at the time of diagnosis (baseline-CAT1) as well as after one year of treatment (end of study-CAT2). The history of exacerbations, hospitalization and visit to GPs related to COPD during the previous 12 months was recorded at baseline and 1 year after the implementation of the recommended treatment. An exacerbation was defined as a worsening of symptoms that required oral corticosteroids and/or antibiotics and/or hospitalization. The presence of cardiovascular disease in general, as well as the presence of systemic hypertension, coronary artery disease, congestive heart failure, arrhythmias or stroke, was specifically recorded.
CAT questionnaire The patients in this study completed the CAT questionnaire that was validated by Jones (1). The CAT consists of eight items, each formatted as a semantic 6-point differential scale, making the tool easy for patients to complete. The items are related to cough and phlegm, chest tightness, breathlessness going up hills/stairs, activity limitations at home, confidence leaving home, sleep and energy. Each item is scored from 0 to 5, giving a total score range from 0 to 40 and providing a reliable measure of the impact of COPD on a patient’s health status. CAT scores are categorized into severity bands, as described in the CAT users guide (http://www.catestonline.org): Low Impact (CAT Copyright © 2014 Informa Healthcare USA, Inc
COPD Assessment Test in primary care
Table 1. Demographic and clinical characteristics of patients with COPD (N = 111) GOLD stage Characteristic
I
II
III
IV
Reported population
Subjects No.
40
52
17
2
111
71.1 ± 8.8
71.1 ± 8.7
70.7 ± 8.9
69.7 ± 10.6
71.1 ± 8.7
0.546
Females
4
8
5
0
17
0.280
Males
36
44
12
2
94
Smoking status Smokers Non-smokers Former smokers
13 3 20
14 7 23
5 2 5
0 0 2
38 21 52
Smoking, pack-years
44.5 ± 38.8
44.2 ± 38.4
45.6 ± 39.8
53.6 ± 35.8
44.4 ± 38.6
0.250
2.36 ± 0.49 a
1.85 ± 0.47 b
1.07 ± 0.31 c
0.68 ± 0.18 c
1.89 ± 0.64
< 0.001
3.49 ± 0.67
2.77 ± 0.66
1.83 ± 0.52
1.78 ± 0.60
2.87 ± 0,86
0.776
0.68 ± 0.03 a
0.67 ± 0.04 a
0.59 ± 0.07 b
0.39 ± 0.03 c
0.65 ± 0.61
< 0.001
Age, years
FEV1, L/sec FVC, L FEV1/FVC COPD Downloaded from informahealthcare.com by University of Laval on 06/05/14 For personal use only.
p value
0.182
Values are expressed as mean ± SD. All spirometric data refer to values after bronchodilation. FEV1: forced expiratory volume in 1 second; FVC: forced vital capacity. Values followed by different letters within lines differ significantly.
score 1 to 10), Medium Impact (11 to 20), High Impact (21 to 30), and Very High Impact (31 to 40) (14). The questionnaire was accessed via www.CATestonline.org and was translated into the Greek language.
Statistical analysis The paired samples t-test was used to test pre- versus post-treatment differences between continuous measurements, while the chi-square test was used for the comparison of proportions. One-way analysis of variance (ANOVA) was employed in order to check differences of continuous measurements among GOLD stages, and the Tukey-Kramer HSD test was used as post-hoc. The Pearson correlation coefficient was used for the assessment of linear relationships between continuous variables. The General Linear Model was used for the assessment of the dependence between the CAT score and FEV1, adjusting for the presence of exacerbations, while binary logistic regression was used to model the probability of exacerbation based on CAT scores. Any p-values less than 0.05 were considered statistically significant. The statistical package SPSS version 17.0 (SPSS Inc., Chicago, IL) and JMP 8.0 (SAS Inst., Cary, NC) were used for data analysis.
Results Of the 1,250 subjects examined (50 subjects × 25 GPs), 172 refused to participate in the second phase of the study (spirometry) or did not meet the ATS/ERS criteria for spirometry. Thus, data on 1,078 subjects (57.1% males, mean age 65.3 ± 11.4 years) were collected and analyzed. The percentage of smokers was 48.4% (38 ± 29 pack-years). We diagnosed 111 (10.3%) patients with COPD who were enrolled in the current extension study. Five patients were withdrawn due to lack of compliance to treatment (3/5) and due to serious adverse event www.copdjournal.com
unrelated to treatment (death 1-stroke 1). In the subgroup of smokers the prevalence of COPD was 17.2% (90/522). The clinical characteristics of COPD patients are summarized in Table 1. The majority of COPD patients were males with a mean age of 71 years, mean smoking history of 44 pack-years and mean FEV1 of 1.89 L (72 ± 21.5% predicted). Most of them (92/111, 82%) were classified in GOLD stages I and II. In one year follow-up, mean FEV1 decreased by 0.06 (95% confidence interval: −0.08, −0.03) and FVC by 0.06 (95% CI: −0.09, −0.02). Following 12 months of treatment, a substantial decrease in the number of exacerbations was also observed from the patients’ medical records (paired t-test, t105 = 4.83, p < 0.001). A proportional decrease was found in the number of visits to GPs (t105 = 7.52, p < 0.001). No difference in the number of hospitalizations (t105 = −0.38, p = 0.71) and the days of hospitalizations (t105 = 0.96, p = 0.34) was noted (Table 2).
CAT scores and COPD severity There was a significant improvement in the mean CAT score following 12 months of treatment by −2.4 (95% CI: −2.9, −1.9); p < 0.001. CAT score increased along with severity according to the GOLD stage, demonstrating impairment in health status of the patients across all stages. This result was found both at baseline (one-way ANOVA, F3,107 = 59.17, p < 0.001) and at the end of the study (F3,102 = 30.98, p < 0.001) (Table 3). A significant correlation between FEV1 and total CAT score was detected at baseline (Pearson correlation, r = −0.583, p < 0.001) and at the end of study as well (r = −0.523, p < 0.001). Association between CAT scores and exacerbations Based on binary logistic regression modeling, we sought to assess if exacerbations lead to poorer health outcomes as measured by the CAT and whether the CAT score
3
4
Papaioannou et al.
COPD Downloaded from informahealthcare.com by University of Laval on 06/05/14 For personal use only.
Table 2. Change of the CAT score, the clinical and lung function parameters after 12 months of treatment
CAT FEV1, L/sec FEV1% pred FVC, L FEV1/FVC Exacerbations Yes No No. of Exacerbations Hospitalizations Yes No No. of hospitalizations Days of hospitalizations Visits to GPs Yes No No. of visits to GPs
Pre-treatment
Post-treatment
p value
10.8 ± 6 1.89 ± 0.64 72 ± 22 2.87 ± 0.86 0.65 ± 0.06
8.4 ± 4.5 1.83 ± 0.61 67 ± 24 2.81 ± 0.83 0.65 ± 0.05
