The prevalence of comorbid depression in adults with diabetes - A meta-analysis

OBJECTIVE - To estimate the odds and prevalence of clinically relevant depr ession in adults with type 1 or type 2 diabetes. Depression is associated w ith hyperglycemia and an increased risk for diabetic complications; relief of depression is associated with improved glycemic control. A more accurate estimate of depression prevalence than what is currently available is need ed to gauge the potential impact of depression management in diabetes. RESEARCH DESIGN AND METHODS - MEDLINE and PsycINFO databases and published references were used to identify studies that reported the prevalence of de pression in diabetes, Prevalence was calculated as an aggregate mean weight ed by the combined number of subjects in the included studies. We used chi (2) statistics and odds ratios (ORs) to assess the rate and likelihood of d epression as a function of type of diabetes, sex, subject source, depressio n assessment method, and study design. RESULTS - A total of 42 eligible studies were identified; 20 (48%) included a nondiabetic comparison group. in the controlled studies, the odds of dep ression in the diabetic group were twice that of the nondiabetic comparison group (OR = 2.0, 95% CI 1.8-2.2) and did not differ by sex, type of diabet es, subject source, or assessment method. The prevalence of comorbid depres sion was significantly higher in diabetic women (28%) than in diabetic men (18%), in uncontrolled (30%) than in controlled studies (21%), in clinical (32%) than in community (20%) samples, and when assessed by self-report que stionnaires (31%) than by standardized diagnostic interviews (11%). CONCLUSIONS - The presence of diabetes doubles the odds of comorbid depress ion. Prevalence estimates are affected by several clinical and methodologic al variables that do nor affect the stability of the ORs.