Prevalence and Correlates of Depressive Disorders in Elderly with Type 2 Diabetes in Primary Health Care Settings

Objective: Depression is associated with poor glycemic control and complications in people with type 2 diabetes. We assessed the prevalence of depressive symptoms and antidepressant medication use among elderly with and without type 2 diabetes and the association between depression and diabetes complications.

Research Design And Methods: In 2004-2006, the Primary Health Care research in Type 2 Diabetes Study applied the Beck Depression Inventory II (BDI-II) to 458 participants with type 2 diabetes (47% male, aged 65 + or -8.9 years, type 2 diabetes duration 19 + or - 8.7 years) and 546 participants without diabetes (non diabetic group) (51% male, aged 59 + or - 8.7 years). Use of antidepressant medication was self-reported. Depressive disorder was defined as a BDI-II score >14 and/or use of antidepressant medication. Occurrence of diabetes complications (retinopathy, blindness, neuropathy, diabetes-related amputation, and kidney or pancreas transplantation) was self-reported.

Results: Mean BDI-II score, adjusted for age and sex, was significantly higher in participants with type 2 diabetes than in non diabetic participants (least-squares mean + or - SE: 7.4 + or - 0.3 vs. 5.0 + or - 0.3; P<0.0001). The prevalence of depressive disorder (as defined by BDI-II>14 and/or antidepressant use) in participants with type 2 diabetes was significantly higher than that of age- and sex-adjusted non diabetic participants (32.1 vs. 16.0%, P<0.0001). Type 2 diabetic participants reported using more antidepressant medications (20.7 vs. 12.1%, P = 0.0003). More type 2 diabetic than non diabetic participants were classified as depressed by BDI-II cut score (17.5 vs. 5.7%, P<0.0001) or by either BDI-II cut score or antidepressant use (32.1 vs. 16.0%, P<0.0001). Participants reporting diabetes complications (n = 209) had higher mean BDI-II scores than those without complications (10.7 + or - 9.3 vs. 6.4 + or - 6.3, P<0.0001).

Conclusions: Depression is highly prevalent in type 2 diabetes and requires further study on assessment and treatment.