Trends and risk factors in severe hypoglycemia among individuals with type 2 diabetes in Korea

Aims: Because of the development of new classes of antidiabetic drugs, hypoglycemic events were expected to decrease. We investigated the trends and risk factors for severe hypoglycemia in subjects with type 2 diabetes in Korea. Methods: We conducted repeated cross-sectional analyses using a Korean National Health Insurance Service–National Sample Cohort from 2006 to 2015. Severe hypoglycemia was defined as hospitalization or a visit to an emergency department with diagnosis of hypoglycemia using ICD-10 codes. Results: During the study period, the prevalence of type 2 diabetes continuously increased. The percentage of patients prescribed metformin and dipeptidyl peptidase-4 inhibitor increased, while the use of sulfonylurea decreased considerably, especially since 2009. The proportion of patients prescribed ≥3 classes of drugs continually increased. Age-standardized incidence of severe hypoglycemia per 1000 patients with diabetes increased from 6.00 to 8.24 between 2006 and 2010, and then fell to 6.49 in 2015. Predictors of severe hypoglycemia included female, older age, comorbidities, polypharmacy, and sulfonylurea or insulin usage. Conclusions: Trends of severe hypoglycemia were associated with changes in drug classes rather than number of antidiabetic drugs. Relentless efforts to reduce the prescription of drugs with a high risk of hypoglycemia should be implemented, particularly for older women with multiple comorbidities.