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

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

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.

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.

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).

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.