Emotional distress predicts reduced type 2 diabetes treatment adherence in the Glycemia Reduction Approaches in Diabetes: A Comparative Effectiveness (GRADE) Study

Abstract

<p dir="ltr">We examined longitudinal associations between emotional distress (specifically, depressive symptoms and diabetes distress) and medication adherence in the GRADE study, a large randomized controlled trial comparing four glucose-lowering medications added to metformin in adults with relatively recent-onset type 2 diabetes mellitus (T2DM). Research Design and Methods: The Emotional Distress Substudy assessed medication adherence, depressive symptoms, and diabetes distress in 1,739 GRADE participants via self-completed questionnaires administered biannually up to 3 years. We examined baseline depressive symptoms and diabetes distress as predictors of medication adherence over 36 months. Bidirectional visit-to-visit relationships were also examined. Treatment satisfaction, beliefs about medication, self-efficacy, and perceived control were evaluated as mediators of longitudinal associations. Results: At baseline, participants (56% White, 17% Hispanic/Latino, 18% Black, 66% male) had a mean (SD) age of 58.0±10.2 years, diabetes duration of 4.2±2.8 years, HbA1c of 7.5±0.5%, and medication adherence of 89.9%±11.1%. Higher baseline depressive symptoms and diabetes distress were independently associated with lower adherence over 36 months (p<0.001). Higher depressive symptoms and diabetes distress at one visit predicted lower adherence at the subsequent 6-month visit (p<0.0001), but not vice versa. Treatment assignment did not moderate relationships. Patient-reported concerns about diabetes medications mediated the largest percentage (11.9-15.5%) of the longitudinal link between emotional distress and adherence. Conclusions: Depressive symptoms and diabetes distress both predict lower adherence to glucose-lowering medications over time among adults with T2DM. Addressing emotional distress and concerns about anticipated negative effects of taking these treatments may be important to support diabetes treatment adherence.</p>