Functional disability as an explanation of the associations between chronic physical conditions and 12-month major depressive episode.
BACKGROUND
The link between physical conditions and mental health is poorly understood. Functional disability could explain the association of physical conditions with major depressive episode (MDE) as an intermediary factor.


METHODS
Data was analyzed from a subsample (N=8796) of the European Study of the Epidemiology of Mental Disorders (ESEMeD), a cross-sectional general population survey. MDE during the last 12 months was assessed using a revision of the Composite International Diagnostic Interview (CIDI 3.0). Lifetime chronic physical conditions were assessed by self-report. Functional disability was measured using a version of the World Health Organization Disability Assessment Schedule (WHODAS). The associations of physical conditions with MDE and explanation by functional disability were quantified using logistic regression.


RESULTS
All physical conditions were significantly associated with MDE. The increases in risk of MDE ranged from 30% for allergy to amply 100% for arthritis and heart disease. When adjusted for physical comorbidity, associations decreased and were no longer statistically significant for allergy and diabetes. Functional disability explained between 17 and 64% of these associations, most substantially for stomach or duodenum ulcer, arthritis and heart disease.


CONCLUSIONS
Due to the cross-sectional nature of the study the temporal relationship of the variables could not be assessed and the amount of explanation cannot simply be interpreted as the amount of mediation.


CONCLUSIONS
Our findings suggest that the association of chronic physical conditions with MDE is partly explained by functional disability. Such explanation is more pronounced for pain causing conditions and heart disease. Health professionals should be particularly aware of the increased risk of depressive disorder when patients experience disability from these conditions.
Stegmann
Mariken E
ME
Interdisciplinary Center for Psychiatric Epidemiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
Ormel
Johan
J
de Graaf
Ron
R
Haro
Josep-Maria
JM
de Girolamo
Giovanni
G
Demyttenaere
Koen
K
Kovess
Vivianne
V
Matschinger
Herbert
H
Vilagut
Gemma
G
Alonso
Jordi
J
Burger
Huibert
H
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease / Q000453:epidemiology / Q000523:psychology*; D015897:Comorbidity; D003431:Cross-Cultural Comparison; D003430:Cross-Sectional Studies; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology; D004185:Disability Evaluation; D005060:Europe; D005260:Female; D006801:Humans; D007406:Interview, Psychological; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012803:Sick Role; D055815:Young Adult