Leveraging benefit design for better diabetes self-management and A1C control.

OBJECTIVES: To evaluate the relationship between cost sharing for blood glucose testing strips and glycemic control rates.

STUDY DESIGN: A retrospective observational study using medical and pharmacy claims data integrated with laboratory glycated hemoglobin (A1C) values for patients using insulin and testing strips. A new user study design was utilized to identify individuals from 14 commercial US health plans who filled testing strips with assumed intention to monitor blood glucose.

METHODS: Patients were divided into low (<20% of annual testing strip cost; n = 3575) and high (≥20%; n = 3580) cost-sharing categories. We compared the likelihood of patients in low and high cost-sharing categories achieving glycemic control (A1C <8.0%) through modified Poisson regression models.

RESULTS: Patients with low cost sharing for testing strips had higher rates of control than those with high cost sharing (58.1% vs 50.3%; P <.001). Low cost sharing was associated with greater probability of glycemic control (adjusted risk ratio [aRR], 1.14; 95% CI, 1.09-1.20; P <.0001). Glycemic control was more likely for patients in areas with median household income greater than $60,000 versus less than $40,000 (aRR, 1.16; 95% CI, 1.07-1.25; P <.01) and greater than $80,000 versus less than $40,000 (aRR, 1.18; 95% CI, 1.06-1.32; P <.01).

CONCLUSIONS: We found a statistically significant correlation between cost sharing for testing strips and better A1C control for patients using insulin medication. Lower cost sharing for testing strips can remove a barrier to diabetes self-management and may lead to improved glycemic control at the population level. Future efforts should study the potential benefits of reducing diabetic complications and associated cost savings.