Hypoglycemia Rates After Restriction of High-Dose Glargine in Hospitalized Patients

Abstract

Hypoglycemia remains one of the main challenges of insulin therapy. To reduce insulin-related hypoglycemia at our institution, we restricted inpatient ordering of high glargine doses (≥0.5 U/kg/day) to endocrine staff in May 2013. This retrospective cohort study assesses its effect on hypoglycemia and glycemic control within 48 hours of admission (ADM). We identified 692 adult patients hospitalized at Boston Medical Center who received glargine upon ADM from November 1, 2012 through April 30, 2013 as the pre-intervention group, and 651 adult patients admitted between November 1, 2013 and April 30, 2014 as the postintervention group. Demographics, medical history, home insulin regimen, concurrent oral diabetes medications or glucocorticoid administration, ADM serum creatinine, all blood glucose levels (BG) ≤48 hours of ADM, and hemoglobin A1c values ≤3 months were assessed. Hypoglycemia was defined as BG ≤70 mg/dL, and hyperglycemia as BG ≥200 mg/dL. Multivariable regression models assessed potential associations between covariates and incidence of hypoglycemia and average BG ≤48 hours of ADM. Demographics were similar between groups. Significantly less patients received high-dose glargine in the post-intervention group (5.2% vs. 0.3%, P<.001). Incidences of hypoglycemia were significantly lower in the postintervention group (20.9% vs. 17.8%, P<.001 per ADM; 3.4% vs. 2.3%, P = .001 per BG measurements [BGM]). Mean BG levels ≤48 hours of ADM and incidence of hyperglycemia were not significantly different. The adjusted incident rate ratio of hypoglycemia was 0.63 per ADM and 0.74 per BGM in the postintervention group compared to the pre-intervention group (P = .001 and P = .063, respectively). We found that implementation of a restriction on high doses of glargine resulted in lower rates of hypoglycemia without worsening glycemic control. ADM = admission BG = blood glucose BGM = blood glucose measurements BMC = Boston Medical Center BMI = body mass index EMR = electronic medical record HgbA1c = hemoglobin A1c IRR = incidence rate ratio NPH = neutral protamine Hagedorn TDD = total daily dose T2D = type 2 diabetes.