Purpose: Among patients with diabetes, major depression is associated with more diabetic complications, lower medication adherence, and poorer self-care of diabetes. We reported earlier that enhanced depression care reduces depression symptoms but not hemoglobin A1c level. This study examined effects of depression interventions on self-management among depressed diabetic patients.
Methods: A total of 329 patients in 9 primary care clinics were randomized to an evidence-based collaborative depression treatment (pharmacotherapy, problem-solving treatment, or both in combination) or usual primary care (routine medical services). Outcome measures included the Summary of Diabetes Self-Care Activities (SDSCA), reported at baseline and 3, 6, and 12 months, and medication non-adherence as assessed by automated pharmacy refill data of oral hypoglycemic agents, lipid-lowering agents, and angiotensin-converting enzyme inhibitors. We used mixed regression models adjusted for baseline differences to compare the intervention with usual care groups at follow-up assessments.
Results: During the 12-month intervention period, enhanced depression care and outcomes were not associated with improved diabetes self-care behaviors (healthy nutrition, physical activity, or smoking cessation). Relative to the usual care group, the intervention group reported a small decrease in body mass index (mean difference = 0.70 kg/m2, 95% CI, 0.17 to 1.24 kg/m2) and a higher rate of nonadherence to oral hypoglycemic agents (mean difference = -6.3%, 95% CI, -11.91% to -0.71%). Adherence to lipid-lowering agents and to antihypertensive medicines was similar for the 2 groups.
Conclusions: In general, diabetes self-management did not improve among the enhanced depression treatment group during a 12-month period, except for small between-group differences of limited clinical importance. Research needs to assess whether self-care interventions tailored for specific conditions, in addition to enhanced depression care, can achieve better diabetes and depression outcomes.