Does emotional distress predict worse glycemic control over time? Results from the Glycemia Reduction Approaches in Diabetes: A Comparative Effectiveness Study
Objectives To evaluate whether baseline levels of depressive symptoms and diabetes specific distress are associated with glycemic control in the GRADE study, a large randomized controlled trial comparing the metabolic effects of four common glucose-lowering medications when combined with metformin in individuals with type 2 diabetes.
Methods The primary and secondary outcomes were defined as an HbA1c value ≥7%, subsequently confirmed, and an HbA1c value ˃7.5%, subsequently confirmed, respectively. Separate Cox proportional hazards models assessed the association between baseline levels of each exposure of interest (depressive symptoms measured by Patient Health Questionnaire (PHQ-8) and diabetes distress measured by Diabetes Distress Scale) and the subsequent risk of metabolic outcome.
Results This substudy included 1,739 participants (56% Non-Hispanic White, 18% Non-Hispanic Black, 17% Hispanic, 68% male, mean [SD] age=58.0 [10.2] years, diabetes duration=4.2 [2.8] years, and HbA1c=7.5% [0.48]). A total of 1,157 participants reached the primary outcome, with time to event of 2.1 years on average, while 738 participants reached the secondary outcome at 3 years on average. Adjusting for sex, race/ethnicity, treatment group, and baseline age, duration of type 2 diabetes, body mass index, and HbA1c, there were no significant associations between the depressive symptoms or diabetes distress and the subsequent risk of the primary or secondary outcomes.
Conclusions The current findings suggest that, at least at for individuals with diabetes of relatively short duration, baseline levels of emotional distress are not associated with glycemic control over time.
