Probing for depression and finding diabetes: a mixed-methods analysis of depression interviews with adults treated for type 2 diabetes.

BACKGROUND: Depression has increased prevalence and consistently predicts poor health outcomes among patients with diabetes. The impact of stressors related to diabetes and its treatment on depression assessment is infrequently considered.
METHODS: We used mixed methods to evaluate depressive symptoms in adults with type 2 diabetes. We categorized responses related to diabetes and its treatment during interviews (n=70) using the Montgomery-Åsberg Depression Rating Scale (MADRS) and administered questionnaires to measure diabetes-related distress and depressive symptoms.
RESULTS: Participants (M age=56, SD=7; 67% female; 64% Black; 21% Latino) had mild depression on average (MADRS M=10, SD=9). Half of those with symptoms spontaneously mentioned diabetes context; 61% said diabetes contributed to their symptoms when questioned directly. Qualitative themes included: overlapping symptoms of diabetes and depression; burden of diabetes treatment; emotional impact of diabetes; and the bidirectional influence of depression and diabetes. Diabetes was mentioned more often at higher levels of depression severity (r=.38, p=.001). Higher HbA1c was associated with mentioning diabetes as a context for depressive symptoms (r=.32, p=.007). Insulin-users mentioned diabetes more often than those on oral medications only (p=.005). LIMITATIONS: MADRS is not a traditional qualitative interview so themes may not provide an exhaustive view of the role of diabetes context in depression assessment. CONCLUSIONS AND CLINICAL IMPLICATIONS: The burden of type 2 diabetes and its treatment often provide an explanatory context for depressive symptoms assessed by structured clinical interviews, the gold standard of depression assessment. Diabetes context may influence accuracy of assessment and should inform intervention planning for those needing treatment.