Insulin Insecurity and Its Subsequent Impact on Emerging Adults and Families of Children With Type 1 Diabetes

Multiple states have passed legislation limiting out-of-pocket insulin costs for individuals on private insurance, including Colorado in 2020. Because disruptions in insulin access are life-threatening for people with type 1 diabetes, this study examined the real-world impact of Colorado's law on patient/parent-reported outcomes.

Patient/parent-reported frequency of insulin insecurity (insulin rationing, running out early, or finding alternative sources of insulin), cost concerns, and most recent insulin out-of-pocket cost were assessed by a clinic-developed survey. Demographics, A1C, and glycemic time in range (TIR; 70-180 mg/dL) were obtained from medical record review. Linear regression models were fit to compare out-of-pocket costs, A1C, and TIR, adjusting for sex, diabetes duration, race/ethnicity, insurance, and age.

Of 184 enrolled participants, 149 responded to insulin insecurity questions, with 34% reporting at least one insulin insecurity behavior. Insulin insecurity was associated with higher monthly insulin costs ($77.60 vs. $19.30, P = 0.004) and A1C (+0.69 ± 0.23%, P = 0.003) and lower TIR (-9.78 ± 4.03%, P = 0.02) compared with insulin security. Similar rates of insecurity were seen in emerging adults (46%, n = 18/39) and those publicly insured (43.5%, n = 10/23). There was no difference in mean copayments between those on public versus private insurance ($39.40 vs. $38.00).

Despite costs falling below the out-of-pocket cap, insulin insecurity remains common among emerging adults and families of youth with type 1 diabetes and is associated with worse glycemia. Further research into root causes of insecurity, such as limitations on early refills, is required.