Regimen-Related Distress, Medication Adherence, and Glycemic Control in Rural African American Women With Type 2 Diabetes Mellitus

Abstract

Background: Regimen-related emotional distress in patients with type 2 diabetes mellitus (T2DM) is associated with poor glycemic control, but the mediators of this relationship are not well described. Objective: This cross-sectional study at baseline examines these relationships, including the specific role of medication adherence in rural African American women. Methods: At baseline in the EMPOWER randomized trial, the investigators collected the following data: Regimen-Related Distress (RRD; subscale of the validated Diabetes Distress Scale), diabetes medications, medication adherence using the Morisky Medication Adherence Scale, and hemoglobin A1C (A1C). Results: The study enrolled 189 rural African American women with T2DM (mean age = 53 ± 11 years, A1C = 9.1% ± 1.8%, body mass index = 37.7% ± 8.2%; 61% on insulin); 56% reported elevated RRD (mean ≥ 3.0), and this was associated with significantly lower medication adherence (4.4 vs 6.4, P < 0.001) and significantly higher A1C (9.5% vs 8.6%, P < 0.001). In multivariate modeling, both elevated RRD (exp β = 2.1; 95% CI = 1.1-4.2; P < 0.05) and lower medication adherence (exp β = 3.3; 95% CI = 1.1-9.6; P < 0.05) were independently associated with higher A1C values. In mediation analysis, medication adherence was a significant mediator of the effects of RRD on A1C. Conclusion: Among rural African American women with T2DM, elevated levels of RRD were common and were associated with higher A1C values, in part via effects on medication adherence. Complex treatment regimens accompanied by psychological distress may be associated with poorer glycemic control.