Mary A M Rogers, Joyce M Lee, Renuka Tipirneni, Tanima Banerjee, Catherine Kim

Type 1 diabetes mellitus, which often originates during childhood, is a lifelong disease that requires intensive daily medical management. Because health care services are critical to patients with this disease, we investigated the frequency of interruptions in private health insurance, and the outcomes associated with them, for working-age adults with type 1 diabetes in the United States in the period 2001-15. We designed a longitudinal study with a nested self-controlled case series, using the Clinformatics Data Mart Database. The study sample consisted of 168,612 adults ages 19-64 with type 1 diabetes who had 2.6 mean years of insurance coverage overall. Of these adults, 24.3 percent experienced an interruption in coverage. For each interruption, there was a 3.6 percent relative increase in glycated hemoglobin. The use of acute care services was fivefold greater after an interruption in health insurance compared to before the interruption and remained elevated when stratified by age, sex, or diabetic complications. An interruption was associated with lower perceived health status and lower satisfaction with life. We conclude that interruptions in private health insurance are common among adults with type 1 diabetes and have serious consequences for their well-being.