Comorbid depression, chronic pain, and disability in primary care.
OBJECTIVE
The objectives of this study were to provide estimates of the prevalence and strength of association between major depression and chronic pain in a primary care population and to examine the clinical burden associated with the two conditions, singly and together.


METHODS
A random sample of Kaiser Permanente patients who visited a primary care clinic was mailed a questionnaire assessing major depressive disorder (MDD), chronic pain, pain-related disability, somatic symptom severity, panic disorder, other anxiety, probable alcohol abuse, and health-related quality of life (HRQL). Instruments included the Patient Health Questionnaire, SF-8, and Graded Chronic Pain Questionnaire. A total of 5808 patients responded (54% of those eligible to participate).


RESULTS
Among those with MDD, a significantly higher proportion reported chronic (i.e., nondisabling or disabling) pain than those without MDD (66% versus 43%, respectively). Disabling chronic pain was present in 41% of those with MDD versus 10% of those without MDD. Respondents with comorbid depression and disabling chronic pain had significantly poorer HRQL, greater somatic symptom severity, and higher prevalence of panic disorder than other respondents. The prevalence of probable alcohol abuse/dependence was significantly higher among persons with MDD compared with individuals without MDD regardless of pain or disability level. Compared with participants without MDD, the prevalence of other anxiety among those with MDD was more than sixfold greater regardless of pain or disability level.


CONCLUSIONS
Chronic pain is common among those with MDD. Comorbid MDD and disabling chronic pain are associated with greater clinical burden than MDD alone.
Department of Psychiatry and Behavioral Sciences, University School of Medicine, Stanford, CA, USA. arnow@stanford.edu
Bruce A
BA
Arnow
Enid M
EM
Hunkeler
Christine M
CM
Blasey
Janelle
J
Lee
Michael J
MJ
Constantino
Bruce
B
Fireman
Helena C
HC
Kraemer
Robin
R
Dea
Rebecca
R
Robinson
Chris
C
Hayward
D000203:Activities of Daily Living; D000328:Adult; D000368:Aged; D000437:Alcoholism / Q000453:epidemiology; D001008:Anxiety Disorders / Q000453:epidemiology; D002140:California / Q000453:epidemiology; D002908:Chronic Disease; D015897:Comorbidity; D003865:Major Depressive Disorder / Q000453:epidemiology*; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000453:epidemiology*; D016584:Panic Disorder / Q000453:epidemiology; D015995:Prevalence; D011788:Quality of Life