Body Mass Index–Mortality Relationship in Severe Hypoglycemic Patients With Type 2 Diabetes

BACKGROUND: Hypoglycemia is associated with a higher risk of death. This study analyzed various body mass index (BMI) categories and mortalities of severe hypoglycemic patients with type 2 diabetes mellitus (DM) in a hospital emergency department. METHODS: The study included 566 adults with type 2 diabetes who were admitted to 1 medical center in Taiwan between 2008 and 2009 with a diagnosis of severe hypoglycemia. Mortality data, demographics, clinical characteristics and the Charlson's Comorbidity Index were obtained from the electronic medical records. Patients were stratified into 4 study groups as determined by the National Institute of Health (NIH) and World Health Organization classification for BMI, and the demographics were compared using the analysis of variance and χ(2) test. Kaplan-Meier's analysis and the Cox proportional-hazards regression model were used for mortality, and adjusted hazard ratios were adjusted for each BMI category among participants. RESULTS: After controlling for other possible confounding variables, BMI <18.5 kg/m(2) was independently associated with low survival rates in the Cox regression analysis of the entire cohort of type 2 DM patients who encountered a hypoglycemic event. Compared to patients with normal BMI, the mortality risk was higher (adjusted hazard ratios = 4.9; 95% confidence interval [CI] = 2.4–9.9) in underweight patients. Infection-related causes of death were observed in 101 cases (69.2%) and were the leading cause of death. CONCLUSIONS: An independent association was observed between BMI less than 18.5 kg/m(2) and mortality among type 2 DM patient with severe hypoglycemic episode. Deaths were predominantly infection related.