Depression and diabetes - Impact of depression symptoms on adherence, function, costs

Background: Depression is common among patients with chronic medical illnes s. We explored the impact of depressive symptoms in primary care patients w ith diabetes on diabetes self-care, adherence to medication regimens, funct ioning, and health care costs. Methods: We administered a questionnaire to 367 patients with types 1 and 2 diabetes from 2 health maintenance organization primary care clinics to ob tain data on demographics, depressive symptoms, diabetes knowledge, functio ning, and diabetes self-care. On the basis of automated data, we measured m edical comorbidity, health care costs, glycosylated hemoglobin (HbA(1c)) le vels, and oral hypoglycemic prescription refills. Using depressive symptom severity tertiles (low, medium, or high), we per formed regression analyses to determine the impact of depressive symptoms on adherence to diabetes se lf-care and oral hypoglycemic regimens, HbA(1c) levels, functional impairme nt, and health care costs. Results: Compared with patients in the low-severity depression symptom tert ile, those in the medium- and high-severity tertiles were significantly les s adherent to dietary recommendations. Patients in the high-severity tertil e were significantly distinct from those in the low-severity tertile by hav ing a higher percentage of days in nonadherence to oral hypoglycemic regime ns (15% vs 7%); poorer physical and mental functioning;; seater probability of having any emergency department, primary care, specialty care, medical inpatient, and mental health costs; and among users of health care within c ategories, higher primary (51% higher), ambulatory (75% higher),and total h ealth care costs (86% higher). Conclusions: Depressive symptom severity is associated with poorer diet and medication regimen adherence, functional impairment, and higher health car e costs in primary care diabetic patients. Further studies testing the effe ctiveness and cost-effectiveness of enhanced models of care of diabetic pat ients with depression are needed.