Weight-Based, Insulin Dose–Related Hypoglycemia in Hospitalized Patients With Diabetes

OBJECTIVE To determine the association of weight-based insulin dose with hypoglycemia in noncritically ill inpatients with diabetes. RESEARCH DESIGN AND METHODS We performed a retrospective, case-control study of 1,990 diabetic patients admitted to hospital wards. Patients with glucose levels <70 mg/dL (case subjects) were matched one to one with nonhypoglycemic control subjects on the basis of the hospital day of hypoglycemia, age, sex, and BMI. RESULTS Relative to 24-h insulin doses <0.2 units/kg, the unadjusted odds of hypoglycemia increased with increasing insulin dose. Adjusted for insulin type, sliding-scale insulin use, and albumin, creatinine, and hematocrit levels, the higher odds of hypoglycemia with increasing insulin doses remained (0.6-0.8 units/kg: odds ratio 2.10 [95% CI 1.08-4.09], P = 0.028; >0.8 units/kg: 2.95 [1.54-5.65], P = 0.001). The adjusted odds of hypoglycemia were not greater in patients who received 0.2-0.4 units/kg (1.08 [0.64-1.81], P = 0.78) or 0.4-0.6 units/kg (1.60 [0.90-2.86], P = 0.11). Although the relationship between insulin dose and hypoglycemia did not vary by insulin type, patients who received NPH trended toward greater odds of hypoglycemia compared with those given other insulins. CONCLUSIONS Higher weight-based insulin doses are associated with greater odds of hypoglycemia independent of insulin type. However, 0.6 units/kg seems to be a threshold below which the odds of hypoglycemia are relatively low. These findings may help clinicians use insulin more safely.