NPH Insulin Versus Insulin Glargine Versus NPH Insulin Plus Insulin Glargine for the Treatment of Dexamethasone-Induced Hyperglycemia in Patients With COVID-19: A Retrospective Cohort Study.

Background: Dexamethasone use in patients hospitalized with COVID-19 significantly reduces mortality; however, it commonly results in hyperglycemia. Optimal treatment of dexamethasone-induced hyperglycemia is not well established.

Objective: The study purpose was to assess the difference in blood glucose (BG) control between insulin glargine, neutral protamine hagedorn (NPH) insulin, and insulin glargine plus NPH insulin for dexamethasone-induced hyperglycemia in patients with type 2 diabetes (T2DM) and COVID-19 infection.

Methods: This retrospective study was conducted in adult inpatients with T2DM and COVID-19 infection who received 6 mg of dexamethasone once daily and insulin during the 5-day study period. The primary outcome was the difference in mean point-of-care (POC) BG levels between study insulins. Secondary outcomes included the incidence of hyperglycemia and hypoglycemia, length of stay, and the percent difference between the mean daily inpatient and home basal insulin doses (for patients who were receiving basal insulin prior to admission in the insulin glargine and insulin glargine and NPH insulin groups only).

Results: Ninety-six patients were included in the analysis (67 insulin glargine, 10 NPH insulin, and 19 insulin glargine plus NPH insulin). The difference in mean POC BG level was not different among groups (254 ± 60 mg/dL vs 234 ± 39 mg/dL vs 250 ± 51 mg/dL, respectively; P = 0.548). There were no significant differences in the secondary outcomes.

Conclusions: No difference in the mean POC BG level was observed. Dexamethasone-induced hyperglycemia was poorly controlled in patients with T2DM and COVID-19 infection.