Continuous Subcutaneous Insulin Infusions vs. Multiple Daily Injections of Insulin in Hospitalized Patients: Glycemic Trends in the First 24 Hours of Admission

Abstract

Background: Continuous subcutaneous insulin infusion (CSII) is a common diabetes treatment modality. Glycemic outcomes of patients using CSII in the first 24 hours of hospitalization have not been well studied. This timeframe is of particular importance because insulin pump settings are programmed to achieve tight outpatient glycemic targets which could result in hypoglycemia when patients are hospitalized. Methods: This retrospective cohort study evaluated 216 hospitalized adult patients using CSII and 216 age-matched controls treated with multiple daily injections (MDI) of insulin. Patients using CSII did not make changes to pump settings in the first 24 hours of admission. Blood glucose (BG) values within the first 24 hours of admission were collected. The primary outcome was frequency of hypoglycemia (BG < 70 mg/dL). Secondary outcomes were frequency of severe hypoglycemia (BG < 40 mg/dL) and hyperglycemia (BG ≥ 180 mg/dL). Results: There were significantly fewer events of hypoglycemia [incident rate ratio (IRR) 0.61, 95% confidence interval (CI) 0.42–0.88, p = 0.007] and hyperglycemia (IRR 0.79, 95% CI 0.65–0.96, p = 0.02) in the CSII group compared to the MDI group. There was a trend toward fewer events of severe hypoglycemia in the CSII group (IRR 0.15, 95% CI 0.02–0.93, p = 0.06). Conclusions: Patients using CSII experienced fewer events of both hypoglycemia and hyperglycemia in the first 24 hours of hospital admission than those treated with MDI. Our study demonstrates that CSII use is safe and effective for the treatment of diabetes within the first 24 hours of hospital admission.