About 20 million U.S. adults with diabetes (DM) used glucose-lowering medications in 2016. We examined insurance coverage for prescription medications and its association with glycemic control in this population, overall and by age group. We used data from 3,311 adults aged ≥18y with self-reported diagnosed DM and treated with oral hypoglycemic agents or insulin in the 2005-2016 National Health and Nutrition Examination Survey. Participants reported on having health insurance that covered any part of prescription costs. Poor glycemic control (poor A1C) was defined as A1C >9%. During 2005-2016, 15.3% (95%CI 13.7-17.1) of treated U.S. adults with DM lacked prescription coverage, including 8.9% (7.9-10.1) who were uninsured and 6.4% (5.2-7.8) who were insured without any prescription coverage. Compared to treated adults ≥65y, the percentage without prescription coverage was 55% higher for treated adults 18-44y (20.3%, 16.3-25.0 vs. 13.1%, 10.7-16.0) and similar for those 45-64y (15.9%, 13.7-18.4). Overall, 21.4% (17.6-25.7) of treated adults without prescription coverage and 13.5% (11.9-15.3) with prescription coverage had poor A1C (prevalence ratio 1.58 [1.25-2.00]). By age group, % poor A1C differed by coverage status for treated adults 18-44y (covered: 24.9% [18.8-32.1]; not covered: 38.9% [28.2-50.8], p=0.034) and those 45-64y (covered: 15.2% [12.8-18.1]; not covered: 25.5% [19.8-32.3], p=0.005) but not for those ≥65y (covered: 7.5% [6.1-9.1]; not covered: 6.4% [4.0-9.9], p=0.29). For those insulin-treated, % poor A1C differed by coverage status only among adults 18-44y (covered: 31.9% [23.4-41.8]; not covered: 70.0% [53.1-82.8], p<0.001). Despite the high usage of medication among U.S. adults with diabetes, about 15% of the treated population has no prescription coverage. Most young adults under 45y without prescription coverage who use insulin have poor glycemic control, signifying a major public health concern.
K.M. Bullard: None. S.R. Benoit: None. S. Saydah: None. C. Mercado: None. G. Imperatore: None.
