The association of physical activity and depression in Type 2 diabetes

Aims Physical inactivity and depressed mood are both associated with a higher likelihood of diabetes-related complications; the association between physical activity and depressed mood in Type 2 diabetes has not been reviewed previously. We have reviewed (i) the strength of this association and (ii) the impact of depression-specific management and physical activity interventions on mood and activity levels in overweight adults with Type 2 diabetes. Methods Studies published between January 1996 and September 2007 were identified (OVID-MEDLINE, PSYCH-INFO and EMBASE) using pertinent search terms (keyword/title). Results Of the 12 studies included (10 cross-sectional, two trials), most employed a standardized questionnaire for depressed mood but only one item for physical activity. In adults with Type 2 diabetes, the inactive are 1.72 to 1.75 times more likely to be depressed than the more active; the depressed are 1.22 to 1.9 times more likely to be physically inactive than the non-depressed. Two randomized trials demonstrated that a depression management programme improved mood, but only one demonstrated increased physical activity. Conclusions Studies to date suggest an association between depressed mood and physical inactivity in adults with Type 2 diabetes, although objective measures of physical activity have not been employed. Depression-specific management may improve mood and possibly activity. A trial comparing the impact of depression-specific management compared with exercise intervention on depressed mood and activity in Type 2 diabetes is justified.