Insulin Glargine in Critically ill Patients: Once/Day versus Twice/Day Dosing

Twice/day dosing of insulin glargine has been used to treat hyperglycemia in clinical practice; however, data supporting its use in the critically ill population are lacking. This study was designed to evaluate the safety and efficacy of twice/day insulin glargine in critically ill patients.

A retrospective study was conducted in adult patients admitted to the intensive care units between February 2013 and June 2017 who received insulin glargine twice/day or 40 units or more once/day for 48 hours or longer. Post cardiovascular surgery patients were excluded. Data were collected for up to 14 patient-days. The efficacy outcomes included the incidence of hyperglycemia (blood glucose [BG] above 180 mg/dl), predose hyperglycemia rate (BG above 180 mg/dl within 4 hrs before the dose), and BG variability (standard deviation). The safety outcome was assessed by the development of hypoglycemia (BG below 70 mg/dl).

A total of 58 patients (twice/day = 23; once/day = 35) were included in the analysis. Demographics were similar between the groups including history of diabetes mellitus, baseline hemoglobin A_1C , and home insulin use. No difference was observed between the twice/day and once/day groups in the mean BG (153 vs 154 mg/dl, p=0.95, respectively), and BG variability (46 vs 44 mg/dl, p=0.29, respectively). Although the overall incidence of hyperglycemia was similar between twice/day and once/day groups (96% vs 97%, p=1.00, respectively), the twice/day group had a significantly lower predose hyperglycemia rate (twice/day 0.27 vs once/day 0.43, p=0.02). Additionally, the twice/day group did not experience an increased incidence of hypoglycemia (twice/day 23% vs once/day 34%, p=0.57) or hypoglycemia without having anything by mouth (twice/day 0% vs once/day 9%, p=0.27).

This is the first study demonstrating that twice/day insulin glargine reduced the rate of predose hyperglycemia without increasing the risk of hypoglycemia in critically ill patients. A large randomized study is needed to confirm the safety and efficacy of twice/day glargine in the critically ill.