Prevalence and predictors of hypoglycemia in South Korea.

OBJECTIVES: This study aimed to identify the prevalence and predictors of hypoglycemia in patients with type 2 diabetes (T2D) using South Korea's nationwide healthcare database. STUDY DESIGN: Retrospective cohort and nested case-control analyses were conducted to estimate the prevalence and predictors of hypoglycemia, respectively. METHODS: A cohort of 2,273,481 patients with T2D was followed to estimate the 1-year prevalence of hypoglycemia. Total hypoglycemia was identified using outpatient, inpatient, or emergency department visit data containing a diagnosis code for hypoglycemia. Severe hypoglycemia was defined as an event with inpatient admission or emergency care. Within the T2D cohort, cases with hypoglycemia were identified, and up to 4 controls were randomly selected after matching by sex, age, and cohort entry date. Possible predictive factors included insurance type, medical institution type, hypoglycemic history, antidiabetic drugs, Charlson Comorbidity Index score, and diabetic complications. We conducted conditional logistic regression analyses to estimate adjusted odds ratios (aORs) and 95% CIs to identify predictors of hypoglycemia. RESULTS: The prevalences of total and severe hypoglycemia were 1.38% and 0.96%, respectively. Those with a history of hypoglycemia had the highest risk for a further hypoglycemic event (aOR, 16.71; 95% CI, 15.62-17.88). Use of combination therapy with insulin and sulfonylurea was highly associated with severe hypoglycemia (aOR, 15.09; 95% CI, 13.60-16.74). Among diabetic complications, the presence of nephropathy was the greatest predictive factor (aOR, 1.79; 95% CI, 1.73-1.85). CONCLUSIONS: Patients with a history of hypoglycemia or receiving combined antidiabetic therapy must be appropriately managed to achieve optimal glycemic control without significant risk of hypoglycemia.