Context: Guidelines recommend scheduled long-acting basal and short-acting bolus insulin several times daily to manage inpatient hyperglycemia. In the "real world," insulin therapy is complicated, with limited data on the comparative effectiveness of different insulin strategies.
Objective: This work aimed to evaluate the association of different insulin strategies with glucose control and hospital outcomes after adjustment for patient and physician factors that influence choice of therapy.
Methods: This retrospective, observational study took place at an academic hospital. Participants included noncritically ill hospitalized medical/surgical patients (n = 4558) receiving subcutaneous insulin for 75% or longer during admission. Insulin therapy was grouped into 3 strategies within the first 48 hours: basal bolus (BB: scheduled long and short/rapid n = 2358), sliding scale (SS: short/rapid acting n = 1855), or basal only (BO: long only: n = 345). Main outcome measures included glucose control: hypoglycemic days, hyperglycemic days, euglycemic days, mean glucose; and hospitalization: in-hospital mortality, length of stay (LOS), and readmissions.
Results: Initial therapy with BB was associated with more hypoglycemic (2.40; CI, 2.04 to 2.82) (P < .001) and fewer euglycemic days (0.90; CI, 0.85 to 0.97) (P = .003) than SS, whereas BO was associated with fewer hyperglycemic days (0.70; CI, 0.62 to 0.79) (P < .001), lower mean glucose (-18.03; CI, -22.46 to -12.61) (P < .001), and more euglycemic days (1.22; CI, 1.09 to 1.37) (P < .001) compared to SS. No difference in mortality, LOS, and readmissions was found. However, decreased LOS was observed in the BB subgroup with a medical diagnostic related group (0.93; CI, 0.89 to 0.97) (P < .001).
Conclusion: BO had a more favorable hyperglycemia profile than SS. BB, on the other hand, showed worse glycemic control as compared to SS. In the real-world hospital, BO may be a simpler and more effective insulin strategy.
Keywords: basal-bolus; hospital; hyperglycemia; hypoglycemia; inpatient; insulin.
© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society.