Negative association of concomitant physical symptoms with the course of major depressive disorder: A systematic review
Received 20 July 2009; received in revised form 2 November 2009; accepted 30 November 2009. published online 22 January 2010.
Abstract
Objective
The prognosis of depression greatly varies among patients, and the physical symptoms that often accompany depression may predict treatment resistance and a worse outcome. If so, this may have important clinical implications. The aim of this systematic review was to explore the association of concomitant physical symptoms with the outcome of major depressive disorder (MDD).
Methods
Systematic review: Medline, Psychinfo, and the Cochrane Library were searched for prospective, cross-sectional, and retrospective studies, and also for open-label trials and randomized controlled trials. The risk of bias assessment and data extraction were performed in duplicate. A qualitative best-evidence synthesis was performed, based on the number of studies reporting on the association between physical symptoms and the course of MDD, the consistency of the results, and the methodological quality. The findings were reported according to the PRISMA guidelines.
Results
Nine studies met the inclusion criteria. Although the design, outcome measures, and data presentation varied too much to make statistical pooling possible, the best evidence synthesis resulted in strong, consistent evidence for a negative association between physical symptoms and the course of MDD.
Conclusion
This systematic review shows a negative association of concomitant physical symptoms with the course of MDD. The effect might be considerable, but the number of studies addressing this topic is small and there was a wide variation in the study designs and outcome measures. More research is needed.
aDepartment of Diagnosis and Treatment, Netherlands Institute of Mental Health and Addiction (Trimbos Institute), Utrecht, The Netherlands
bDepartment of General Practice and the EMGO+ Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
cArthritis Research Campaign National Primary Care Centre, Keele University, Keele, United Kingdom
dDepartment of Psychiatry and the EMGO+ Institute for Health and Care Research, VU University Medical Care Center, Amsterdam, The Netherlands
eDepartment of Clinical and Developmental Psychology, University of Tilburg, Tilburg, The Netherlands
Corresponding author. Department of Diagnosis and Treatment, Netherlands Institute of Mental Health and Addiction (Trimbos Institute), PO Box 725, 3500 AS Utrecht, The Netherlands. Tel.: +31 30 2971185; fax: +31 30 2971111.
ABSTRACT