511675
2013
APY22110.1177/1039856213511675Australasian PsychiatryMohan et al.
AP
Somatoform disorders
Somatoform disorders in patients with chronic pain
Australasian Psychiatry 2014, Vol 22(1) 66–70 © The Royal Australian and New Zealand College of Psychiatrists 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1039856213511675 apy.sagepub.com
Indra Mohan Consultant Psychiatrist, The Northern Hospital – Psychiatry, Epping, VIC, Australia Christine Lawson-Smith Consultation-Liaison Psychiatrist, Royal Perth Hospital, Perth, WA, Australia David A Coall Senior Lecturer, School of Medical Sciences, Edith Cowan University, Joondalup, WA; Adjunct Research Fellow, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Perth, WA, Australia Gillian Van der Watt Senior Research officer, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Perth, WA, Australia
Aleksandar Janca Winthrop Professor and Head of School, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Perth, WA, Australia
Abstract Objective: To assess the frequency and characteristics of somatoform disorders in patients with chronic pain. Method: The study took place in the psychiatric outpatient clinic of a rehabilitation hospital. Participants were interviewed using the World Health Organization Somatoform Disorders Schedule (WHO-SDS) version 2.0. Thirty new and 30 current attendees to the clinic were interviewed following referral by pain medicine specialists. Results: Somatoform disorders were commonly co-morbid with chronic pain in the study population. Persistent somatoform pain disorder (PSPD) was the commonest somatoform disorder. There was a significant difference between women and men suffering from somatic autonomic dysfunction (SAD). Conclusions: The findings of this study confirm that somatoform disorders are common co-morbid diagnoses in patients with chronic pain. Combining psychological treatments with medication, appropriate physical treatments and attending to social issues, may indeed improve the well-being of such patients. Keywords: somatoform disorders, chronic pain, persistent somatoform pain disorder, somatisation, somatoform autonomic dysfunction
P
ain is ubiquitous in medical practice, causing significant distress and disability.1,2 The co-morbidity of chronic pain and psychiatric disorders (in particular depression and anxiety) has long been known.3–7 Somatisation, known to occur in patients with chronic pain, is also a common, costly problem encountered in health care, involving not only ever-increasing treatment expenses, but also significant costs to families and the community through unemployment and ‘sick days’ off work.8,9 There has been a major, philosophical shift in the concept of ‘somatisation’, a term regarded by many, along with ‘medically unexplained symptoms’, as rather pejorative.10–12 Nevertheless, patients who have clusters of functional symptoms in addition to their chronic pain, are difficult to treat. Considerable research world-wide has been undertaken to understand better the complexities of these patients; this includes sophisticated imaging techniques that not only demonstrate the cerebral changes that occur in chronic pain, but also the effects of certain treatments.5,13 The aim of this study was to establish the frequency and characteristics of somatoform disorders in patients with
chronic pain attending an outpatient psychiatric clinic in a rehabilitation hospital in Western Australia. To our knowledge, there is no published outpatient study that has explored somatoform disorders in patients with chronic pain in Australia.
Methods
Design and participants The study was not funded and participants were interviewed using the World Health Organization Somatoform Disorders Schedule (WHO-SDS) version 2.0.14,15 The sample consisted of 60 patients referred to the psychiatric outpatients’ clinic by pain medicine specialists; 30 were new attendees and 30 were current attendees. All patients suffered from chronic pain. Approval for the study was obtained from the Royal Perth Hospital Ethics Correspondence: Indra Mohan, Consultant Psychiatrist, The Northern Hospital – Psychiatry, 185 Cooper Street, Epping, VIC 3076, Australia. Email: [email protected]
66 Downloaded from apy.sagepub.com at UCSF LIBRARY & CKM on March 25, 2015
Mohan et al.
Committee. An information sheet about the study was provided for participants and their informed consent was gained prior to inclusion in the study. Patients could withdraw from the study at any time. Confidentiality of the information obtained was assured. Participants had to be aged between 18 and 60 years to be included in the study. In addition, they had to be referred by pain medicine specialists who suspected psychological symptoms were present and that their patients would benefit from a psychiatric assessment. Participants also had to have suffered from chronic pain for a period of at least 6 months and informed consent had to be obtained. Patients with a moderate to severe intellectual disability, a significant physical disability, dementia, significant speech or hearing difficulties were excluded from the study. Patients using illicit drugs or were alcohol dependent were excluded, as were people with a psychotic illness and those with suicidal ideation. Data collection The sample was assessed using the WHO-SDS (version 2.0), which is a reliable and valid instrument for the detection and assessment of somatic symptoms.14–16 Training in the use of the instrument was provided. The data collectors were a consultation-liaison psychiatrist and a psychiatric registrar. On average, an hour was spent gathering the data from each patient. Statistical analyses The sample size calculations were performed using the STASTICA data analysis software system, taking into account that the expected frequency of somatoform disorders within pain clinic settings is at least 20%, with
and accuracy of +/–1%. A total of 50 patients would be required for 95% power, assuming a type 1 error rate of alpha=0.05. Therefore, a sample size of 60 would ensure sufficient power. Pearson’s zero-order correlations and t-tests were used to examine the bivariate relationships between continuous and categorical variables. Chi-squared tests explored differences in proportions between categorical variables. The independent influences of gender and age on the duration of persistent somatoform pain disorder (PSPD) and the duration of somatoform autonomic dysfunction (SAD) were examined using the linear regression procedure in IBM SPSS Statistics 19. In all cases, the unstandardised regression coefficient (B) is reported, which shows the change in the dependent variable that results from a one unit change in the explanatory variable.
Results The number of participants in the study was 60. The majority were female (58%) and the mean age was 45.6 (+/– 9.34) years. Forty-three percent of participants were married and 33% were separated or divorced. Only 23.3% of participants were employed at the time of the study, while the majority (71.1%) had been unemployed for at least 12 months prior to the study. Two participants were studying at secondary educational colleges. The majority of participants (75%) had completed 10 years or more of schooling. There were no significant differences between male and female participants on socio-demographic variables. PSPD was seen in 83% of patients, satisfying both the Diagnostic and Statistical Manual 4th edition (DSM-1V)17 and the International Classification of Diseases 10th edition (ICD-10)18 diagnostic classification schedules. PSPD was of lengthy duration i.e.: 17.3 (+/-14.7) years. Very
Table 1. Study population characteristicsa (n=60) Variables Persistent Somatoform Pain Disorder (F45.4) Present Absent Assessment impossible Number of factors Duration (years) Treatments (four or more different treatments) Number of professionals in last 12 months General health (most of life) Excellent Good Fair Poor aVariability
n
Mean (%)
50 1 9 50 50 10
83% 2% 15% 2.4 17.3 16.9% 27.8
4 18 12 24
7% 30% 20% 40%
SD
1.6 14.7
Range 0–6 0–58 5–130
in sample size due to missing values. 67 Downloaded from apy.sagepub.com at UCSF LIBRARY & CKM on March 25, 2015
Australasian Psychiatry 22(1)
Table 2. Participants who received specific treatments Treatment
Total
n
%
n
%
n
%
Medicine Psychotherapy or counseling Surgery Acupuncture Other treatment Other alternative treatment
59a 34 19 13 16 6
100 58 32 22 27 10
34a 21 10 8 7 6
100 62 29 24 21 18
25 13 9 5 9 0
100 52 36 20 36 0
aVariability
Female
Male
in sample size due to missing values.
Table 3. Impact of symptoms on participants Symptom
Total (n = 60)
Persistent somatoform pain disorder (F45.4) Present (n = 50) Absent (n = 10)
Somatoform disorders Bothered a great deal for 6 months or more by pains Pains kept you from working/seeing friends Pains last experienced less than 2 weeks ago Digestive system problems interfered with normal activities Digestive system problems last experienced less than 2 weeks ago Bodily problems (B25–B46) interfered with normal activities Bodily problems (B25–B46) last experienced less than 2 weeks ago Bodily problems (B50–B61) interfered with normal activities Bodily problems (B50–B61) last experienced less than 2 weeks ago Hypochondriasis Worry about condition interfere with life Worry about condition last experienced less than 2 weeks ago Neurasthenia Feeling tired interfered with normal activities Feeling tired last experienced less than 2 weeks ago
n
%
n
%
n
%
49 46 50 16 28 18 25 18 17
82 77 83 27 47 43b 86b 43b 59b
49 46 49 12 23 14 20 15 13
100b 100b 98 24 46 40b 83b 42b 52b
0 0 1 4 5 4 5 3 4
0 0 10 40 50 57b 50 50b 100b
15 15
98b 83b
12 12
85b 86b
3 3
100b 75b
45 43
96b 92b
43 42
98b 98b
1 1
25b 10
aVariability
in sample size due to missing values. out of those individuals reporting symptom due to missing cases. The selection criteria for symptoms to be included in this list were those symptom that were experienced by 25% or more (n = 15) of the total sample (nw = 60). bPercentage
few (7%) rated their health as excellent and 40% rated their health as being poor (Table 1). All participants received medications irrespective of gender. Fewer male than female participants had received psychotherapy or counselling (male 52% compared to female 62%). Other treatments, such as surgery or acupuncture, were less commonly undertaken (Table 2). All participants who
had PSPD complained of disturbing pains which interfered with their quality of life, including their ability to work and socialise (Table 3). Chest pains (48%), pounding of the heart (56%) and headaches (48%) were amongst the commonest complaints. Sleep difficulties (84%), impatience, irritability associated with fatigue (86%) and an inability to relax (85%) were commonly
68 Downloaded from apy.sagepub.com at UCSF LIBRARY & CKM on March 25, 2015
Mohan et al.
Table 4. Symptoms experienced by participants Symptom
Total (n = 60)
Persistent somatoform pain disorder (F45.4) Present (n = 50) Absent (n = 10)
Somatoform disorders Chest pains Headaches Stomach churning Lump in throat Periods of weakness Trouble keeping balance Body shook a lot Shortness of breath Heavy and fast breathing Heart pounding Heaviness or lightness Skin blotchiness Sex was not pleasurable Hypochondriasis Worry about serious physical illness/deformity Neurasthenia Tired all the time Get easily tired Weakness/exhaustion from little effort Difficult to recover from fatigue Dizziness during fatigue Sleep difficulties during fatigue Impatient/irritable during fatigue Unable to relax during fatigue
n
%
n
%
n
%
26 25 21 16 22 17 18 25 23 31 15 17 15
43 40 35 27 37 28 30 42 38 52 25 28 25
24 24 19 15 21 15 16 21 22 28 14 14 12
48 48 38 30 42 30 32 42 44 56 28 28 24
2 0 2 1 1 2 2 4 1 3 1 3 3
20 0 20 10 10 20 20 40 10 30 10 30 30
16
27
12
24
4
40
36 35 24 22 19 39 40 46
60 58 40 37 32 65 67 77
33 33 23 22 17 36 37 36
66 66 46 50b 39b 84b 86b 85b
3 2 1 0 2 3 3 3
30 20 10 0 50b 75b 75b 75b
aVariability
in sample size due to missing values. out of those individuals reporting symptom due to missing cases. The selection criteria for symptoms to be included in this list were those symptom that were experienced by 25% or more (n = 15) of the total sample (n = 60). bPercentage
reported amongst those who were diagnosed as having co-morbid neurasthenia and PSPD (Table 4). The analysis used the DSM-IV diagnosis of PSPD, which was also consistent with ICD-10 criteria.17,18 Spearman’s rho was used to assess associations between continuous variables with PSPD. A diagnosis of PSPD was associated with more of these patients with this disorder consulting more health professionals in the last year (r=.257, p
2013
APY22110.1177/1039856213511675Australasian PsychiatryMohan et al.
AP
Somatoform disorders
Somatoform disorders in patients with chronic pain
Australasian Psychiatry 2014, Vol 22(1) 66–70 © The Royal Australian and New Zealand College of Psychiatrists 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1039856213511675 apy.sagepub.com
Indra Mohan Consultant Psychiatrist, The Northern Hospital – Psychiatry, Epping, VIC, Australia Christine Lawson-Smith Consultation-Liaison Psychiatrist, Royal Perth Hospital, Perth, WA, Australia David A Coall Senior Lecturer, School of Medical Sciences, Edith Cowan University, Joondalup, WA; Adjunct Research Fellow, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Perth, WA, Australia Gillian Van der Watt Senior Research officer, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Perth, WA, Australia
Aleksandar Janca Winthrop Professor and Head of School, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Perth, WA, Australia
Abstract Objective: To assess the frequency and characteristics of somatoform disorders in patients with chronic pain. Method: The study took place in the psychiatric outpatient clinic of a rehabilitation hospital. Participants were interviewed using the World Health Organization Somatoform Disorders Schedule (WHO-SDS) version 2.0. Thirty new and 30 current attendees to the clinic were interviewed following referral by pain medicine specialists. Results: Somatoform disorders were commonly co-morbid with chronic pain in the study population. Persistent somatoform pain disorder (PSPD) was the commonest somatoform disorder. There was a significant difference between women and men suffering from somatic autonomic dysfunction (SAD). Conclusions: The findings of this study confirm that somatoform disorders are common co-morbid diagnoses in patients with chronic pain. Combining psychological treatments with medication, appropriate physical treatments and attending to social issues, may indeed improve the well-being of such patients. Keywords: somatoform disorders, chronic pain, persistent somatoform pain disorder, somatisation, somatoform autonomic dysfunction
P
ain is ubiquitous in medical practice, causing significant distress and disability.1,2 The co-morbidity of chronic pain and psychiatric disorders (in particular depression and anxiety) has long been known.3–7 Somatisation, known to occur in patients with chronic pain, is also a common, costly problem encountered in health care, involving not only ever-increasing treatment expenses, but also significant costs to families and the community through unemployment and ‘sick days’ off work.8,9 There has been a major, philosophical shift in the concept of ‘somatisation’, a term regarded by many, along with ‘medically unexplained symptoms’, as rather pejorative.10–12 Nevertheless, patients who have clusters of functional symptoms in addition to their chronic pain, are difficult to treat. Considerable research world-wide has been undertaken to understand better the complexities of these patients; this includes sophisticated imaging techniques that not only demonstrate the cerebral changes that occur in chronic pain, but also the effects of certain treatments.5,13 The aim of this study was to establish the frequency and characteristics of somatoform disorders in patients with
chronic pain attending an outpatient psychiatric clinic in a rehabilitation hospital in Western Australia. To our knowledge, there is no published outpatient study that has explored somatoform disorders in patients with chronic pain in Australia.
Methods
Design and participants The study was not funded and participants were interviewed using the World Health Organization Somatoform Disorders Schedule (WHO-SDS) version 2.0.14,15 The sample consisted of 60 patients referred to the psychiatric outpatients’ clinic by pain medicine specialists; 30 were new attendees and 30 were current attendees. All patients suffered from chronic pain. Approval for the study was obtained from the Royal Perth Hospital Ethics Correspondence: Indra Mohan, Consultant Psychiatrist, The Northern Hospital – Psychiatry, 185 Cooper Street, Epping, VIC 3076, Australia. Email: [email protected]
66 Downloaded from apy.sagepub.com at UCSF LIBRARY & CKM on March 25, 2015
Mohan et al.
Committee. An information sheet about the study was provided for participants and their informed consent was gained prior to inclusion in the study. Patients could withdraw from the study at any time. Confidentiality of the information obtained was assured. Participants had to be aged between 18 and 60 years to be included in the study. In addition, they had to be referred by pain medicine specialists who suspected psychological symptoms were present and that their patients would benefit from a psychiatric assessment. Participants also had to have suffered from chronic pain for a period of at least 6 months and informed consent had to be obtained. Patients with a moderate to severe intellectual disability, a significant physical disability, dementia, significant speech or hearing difficulties were excluded from the study. Patients using illicit drugs or were alcohol dependent were excluded, as were people with a psychotic illness and those with suicidal ideation. Data collection The sample was assessed using the WHO-SDS (version 2.0), which is a reliable and valid instrument for the detection and assessment of somatic symptoms.14–16 Training in the use of the instrument was provided. The data collectors were a consultation-liaison psychiatrist and a psychiatric registrar. On average, an hour was spent gathering the data from each patient. Statistical analyses The sample size calculations were performed using the STASTICA data analysis software system, taking into account that the expected frequency of somatoform disorders within pain clinic settings is at least 20%, with
and accuracy of +/–1%. A total of 50 patients would be required for 95% power, assuming a type 1 error rate of alpha=0.05. Therefore, a sample size of 60 would ensure sufficient power. Pearson’s zero-order correlations and t-tests were used to examine the bivariate relationships between continuous and categorical variables. Chi-squared tests explored differences in proportions between categorical variables. The independent influences of gender and age on the duration of persistent somatoform pain disorder (PSPD) and the duration of somatoform autonomic dysfunction (SAD) were examined using the linear regression procedure in IBM SPSS Statistics 19. In all cases, the unstandardised regression coefficient (B) is reported, which shows the change in the dependent variable that results from a one unit change in the explanatory variable.
Results The number of participants in the study was 60. The majority were female (58%) and the mean age was 45.6 (+/– 9.34) years. Forty-three percent of participants were married and 33% were separated or divorced. Only 23.3% of participants were employed at the time of the study, while the majority (71.1%) had been unemployed for at least 12 months prior to the study. Two participants were studying at secondary educational colleges. The majority of participants (75%) had completed 10 years or more of schooling. There were no significant differences between male and female participants on socio-demographic variables. PSPD was seen in 83% of patients, satisfying both the Diagnostic and Statistical Manual 4th edition (DSM-1V)17 and the International Classification of Diseases 10th edition (ICD-10)18 diagnostic classification schedules. PSPD was of lengthy duration i.e.: 17.3 (+/-14.7) years. Very
Table 1. Study population characteristicsa (n=60) Variables Persistent Somatoform Pain Disorder (F45.4) Present Absent Assessment impossible Number of factors Duration (years) Treatments (four or more different treatments) Number of professionals in last 12 months General health (most of life) Excellent Good Fair Poor aVariability
n
Mean (%)
50 1 9 50 50 10
83% 2% 15% 2.4 17.3 16.9% 27.8
4 18 12 24
7% 30% 20% 40%
SD
1.6 14.7
Range 0–6 0–58 5–130
in sample size due to missing values. 67 Downloaded from apy.sagepub.com at UCSF LIBRARY & CKM on March 25, 2015
Australasian Psychiatry 22(1)
Table 2. Participants who received specific treatments Treatment
Total
n
%
n
%
n
%
Medicine Psychotherapy or counseling Surgery Acupuncture Other treatment Other alternative treatment
59a 34 19 13 16 6
100 58 32 22 27 10
34a 21 10 8 7 6
100 62 29 24 21 18
25 13 9 5 9 0
100 52 36 20 36 0
aVariability
Female
Male
in sample size due to missing values.
Table 3. Impact of symptoms on participants Symptom
Total (n = 60)
Persistent somatoform pain disorder (F45.4) Present (n = 50) Absent (n = 10)
Somatoform disorders Bothered a great deal for 6 months or more by pains Pains kept you from working/seeing friends Pains last experienced less than 2 weeks ago Digestive system problems interfered with normal activities Digestive system problems last experienced less than 2 weeks ago Bodily problems (B25–B46) interfered with normal activities Bodily problems (B25–B46) last experienced less than 2 weeks ago Bodily problems (B50–B61) interfered with normal activities Bodily problems (B50–B61) last experienced less than 2 weeks ago Hypochondriasis Worry about condition interfere with life Worry about condition last experienced less than 2 weeks ago Neurasthenia Feeling tired interfered with normal activities Feeling tired last experienced less than 2 weeks ago
n
%
n
%
n
%
49 46 50 16 28 18 25 18 17
82 77 83 27 47 43b 86b 43b 59b
49 46 49 12 23 14 20 15 13
100b 100b 98 24 46 40b 83b 42b 52b
0 0 1 4 5 4 5 3 4
0 0 10 40 50 57b 50 50b 100b
15 15
98b 83b
12 12
85b 86b
3 3
100b 75b
45 43
96b 92b
43 42
98b 98b
1 1
25b 10
aVariability
in sample size due to missing values. out of those individuals reporting symptom due to missing cases. The selection criteria for symptoms to be included in this list were those symptom that were experienced by 25% or more (n = 15) of the total sample (nw = 60). bPercentage
few (7%) rated their health as excellent and 40% rated their health as being poor (Table 1). All participants received medications irrespective of gender. Fewer male than female participants had received psychotherapy or counselling (male 52% compared to female 62%). Other treatments, such as surgery or acupuncture, were less commonly undertaken (Table 2). All participants who
had PSPD complained of disturbing pains which interfered with their quality of life, including their ability to work and socialise (Table 3). Chest pains (48%), pounding of the heart (56%) and headaches (48%) were amongst the commonest complaints. Sleep difficulties (84%), impatience, irritability associated with fatigue (86%) and an inability to relax (85%) were commonly
68 Downloaded from apy.sagepub.com at UCSF LIBRARY & CKM on March 25, 2015
Mohan et al.
Table 4. Symptoms experienced by participants Symptom
Total (n = 60)
Persistent somatoform pain disorder (F45.4) Present (n = 50) Absent (n = 10)
Somatoform disorders Chest pains Headaches Stomach churning Lump in throat Periods of weakness Trouble keeping balance Body shook a lot Shortness of breath Heavy and fast breathing Heart pounding Heaviness or lightness Skin blotchiness Sex was not pleasurable Hypochondriasis Worry about serious physical illness/deformity Neurasthenia Tired all the time Get easily tired Weakness/exhaustion from little effort Difficult to recover from fatigue Dizziness during fatigue Sleep difficulties during fatigue Impatient/irritable during fatigue Unable to relax during fatigue
n
%
n
%
n
%
26 25 21 16 22 17 18 25 23 31 15 17 15
43 40 35 27 37 28 30 42 38 52 25 28 25
24 24 19 15 21 15 16 21 22 28 14 14 12
48 48 38 30 42 30 32 42 44 56 28 28 24
2 0 2 1 1 2 2 4 1 3 1 3 3
20 0 20 10 10 20 20 40 10 30 10 30 30
16
27
12
24
4
40
36 35 24 22 19 39 40 46
60 58 40 37 32 65 67 77
33 33 23 22 17 36 37 36
66 66 46 50b 39b 84b 86b 85b
3 2 1 0 2 3 3 3
30 20 10 0 50b 75b 75b 75b
aVariability
in sample size due to missing values. out of those individuals reporting symptom due to missing cases. The selection criteria for symptoms to be included in this list were those symptom that were experienced by 25% or more (n = 15) of the total sample (n = 60). bPercentage
reported amongst those who were diagnosed as having co-morbid neurasthenia and PSPD (Table 4). The analysis used the DSM-IV diagnosis of PSPD, which was also consistent with ICD-10 criteria.17,18 Spearman’s rho was used to assess associations between continuous variables with PSPD. A diagnosis of PSPD was associated with more of these patients with this disorder consulting more health professionals in the last year (r=.257, p
