Comparison between adherence assessments and blood glucose monitoring measures to predict glycemic control in adults with type 1 diabetes: a cross-sectional study

BACKGROUND Adherence to treatment has been defined as the degree to which a patient's behavior corresponds to medical or health advice; however, the most appropriate method to evaluate adherence to diabetes care has yet to be identified. We conducted analyses to compare adherence assessments and blood glucose monitoring measures with regard to their ability to predict glycemic control in adults with type 1 diabetes. METHODS We analyzed four instruments to evaluate adherence: Self-Care Inventory-Revised, a self-administered survey; Diabetes Self-Monitoring Profile (DSMP), administered by trained researchers; a categorical (yes/no/sometimes) adherence self-evaluation; and a continuous (0-100) adherence self-evaluation. Blood glucose monitoring frequency was evaluated by self-report, diary, and meter download. RESULTS Participants (n = 82) were aged 39.0 ± 13.1 years with a mean diabetes duration of 21.2 ± 11.1 years; 27 % monitored blood glucose >4 times/day. The DSMP score was the strongest predictor of glycemic control (r = -0.32, P = 0.004) among adherence assessments, while blood glucose monitoring frequency assessed by meter download was the strongest predictor among blood glucose monitoring measures (r = -40, P < 0.001). All the self-report assessments had a significant but weak correlation with glycemic control (r ≤ 0.28, P ≤ 0.02). The final adjusted model identified the assessment of blood glucose monitoring frequency by meter download as the most robust predictor of HbA1c (estimate effect size = -0.58, P = 0.003). CONCLUSIONS In efforts to evaluate adherence, blood glucose monitoring frequency assessed by meter download has the strongest relationship with glycemic control in adults with type 1 diabetes.