Hospitalization for Hypoglycemia in Japanese Diabetic Patients: A Retrospective Study Using a National Inpatient Database, 2008–2012

We aimed to elucidate the epidemiology, patient demographics, and clinical outcomes of hospitalization for hypoglycemia in diabetic patients using a Japanese large-scale database. We conducted a retrospective study using a national inpatient database of acute care hospitals in Japan. Diabetic patients ages ≥15 years with hypoglycemia as a main diagnosis for hospitalization were eligible. We estimated the annual number of hospitalizations in Japan and compared the annual admission rate by age and treatment groups. We also analyzed the association between patient characteristics and in-hospital mortality. Among 22.7 million discharge records from July 2008 and March 2013, a total of 25,071 patients were eligible. The mean age was 73.4 years, and the mean body mass index (BMI) was 22.3 kg/m(2). The estimated annual hospitalization for hypoglycemia in Japan was ∼20,000. Annual admission rates for hypoglycemia per 1000 diabetic patients and 1000 diabetic patients receiving insulin or oral hypoglycemic agents were 2.1 and 4.1, respectively. Patients <40 years and >70 years old were at a higher risk of hospitalization. In-hospital mortality was 3.8%, and risk factors associated with poor survival were male sex, older age, lower bed capacity, community hospital, low BMI, coma at admission, and higher Charlson Comorbidity Index. To prevent severe hypoglycemia that leads to death and complications, individualized and careful glycemic control are important, especially in very old or young patients and in those with comorbid conditions or low BMI.