Impact of Race and Ethnicity on Severe Hypoglycemia Associated with Sulfonylurea Use for Type 2 Diabetes among Veterans

Sulfonylureas are associated with hypoglycemia. Whether a racial/ethnic disparity in this safety outcome exists is unknown. We sought to assess the impact of race/ethnicity on severe hypoglycemia associated with sulfonylurea use for type 2 diabetes (T2D). Using Veterans Affairs and Medicare data, Veterans initially receiving metformin monotherapy for T2D between 2004 and 2006 were identified. Sulfonylurea use (either alone or via the addition of a prescription for a sulfonylurea to metformin) was captured and compared to remaining on metformin alone during the follow-up period (2007–2016). Hazard ratios (HR) and 95% confidence intervals (CI) from longitudinal competing risk Cox models were used to measure the association between sulfonylurea use and severe hypoglycemia defined as hospitalization for hypoglycemia. A total of 113,668 Veterans with T2D were included. A higher risk of severe hypoglycemia was associated with the receipt of sulfonylurea prescriptions versus remaining on metformin alone across all groups. The effect was largest among Hispanic Veterans (HR: 7.59, 95%CI:4.32–13.33), followed by Veterans in the other race/ethnicity cohort (HR: 4.57, 95%CI:2.50–8.36) and Non-Hispanic Black Veterans (HR: 3.67, 95%CI:2.78–4.85). The effect was smallest among Non-Hispanic White Veterans (HR: 3.11, 95%CI:2.77–3.48). In conclusion, a higher risk of severe hypoglycemia associated with sulfonylurea prescriptions was observed across all analyses. The relationship was most pronounced for Hispanic Veterans, who had nearly 8 times the risk of severe hypoglycemia with sulfonylureas versus remaining on metformin alone.