Insulin Dosing and Glycemic Outcomes Among Steroid-treated Hospitalized Patients

Objective: To determine the optimal insulin-to-steroid dose ratio for the attainment of glycemic control in hospitalized patients. Methods: We retrospectively studied data collected from the electronic health records within an academic medical center from 18 599 patient-days where patients were treated concurrently with insulin and steroids. Multivariate logistic regression analyses, which included demographic and clinical variables, were performed to assess the relationships between the exposures of total and basal insulin-to-steroid ratios and the outcomes of glycemic control (all blood glucose readings on the following patient-day were >70 and ≤180 mg/dL) and hypoglycemia within 3 subgroups of steroid dosing: low (≤10-mg prednisone equivalent dose [PED]), medium (from >10-mg to ≤40-mg PED), and high (>40-mg PED). Results: Increased insulin-to-steroid ratio was associated with increased odds of both glycemic control and hypoglycemia. The optimal total insulin-to-steroid ratio for attaining glycemic control was 0.294 U/kg/10-mg PED in the low-dose subgroup, 0.257 U/kg/10-mg PED in the medium-dose subgroup, and 0.085 U/kg/10-mg PED in the high-dose subgroup. The optimal basal insulin-to-steroid ratio was 0.215 U/kg/10-mg PED in the low-dose subgroup, 0.126 U/kg/10-mg PED in the medium-dose subgroup, and 0.036 U/kg/10-mg PED in the high-dose subgroup. Conclusion: Increasing insulin-to-steroid ratios are positively associated with glycemic control and hypoglycemia. Our study suggests that approximately 0.3 U/kg/10-mg PED is an optimal dose for low- and medium-dose steroids, whereas approximately 0.1 U/kg/10-mg PED is an optimal dose for high-dose steroids. Further prospective studies are needed to identify insulin regimens that will optimize glycemic control in steroid-treated patients while minimizing the risk of hypoglycemia.