This study evaluated the safety and efficacy of two insulin regimens for inpatient hyperglycemia management: combination short-plus long-acting insulin (basal-bolus insulin regimen, BBIR) vs. short-acting insulin only (correctional insulin only regimen, CIOR).
Chart reviews identified noncritically ill patients with pre-existing type 2 diabetes mellitus receiving insulin injections. Study participants (N = 138) were divided into BBIR (N = 104) and CIOR (N = 34) groups. Data for the entire duration of each patient’s stay were analyzed.
The primary outcome of percent hyperglycemic days was higher in BBIR vs. CIOR (3.97 ± 0.33% vs. 1.22 ± 0.38%). The safety outcome of percent hypoglycemic events was not different between BBIR and CIOR (0.78 ± 0.22% vs. 0.53 ± 0.37%). Regarding secondary outcomes, the percentage of euglycemic days was lower in BBIR vs. CIOR (26.74 ± 2.97% vs. 40.98 ± 5.91%). Overall blood glucose (BG) and daily insulin dose were higher in BBIR vs. CIOR (231.43 ± 5.37 vs. 195.55 ± 6.25 mg/dL and 41.36 ± 3.07 vs. 5.02 ± 0.68 units, respectively). Insulin regimen-associated differences in hyperglycemia and daily insulin dose persisted after adjusting for covariates.
Our observations linking BBIR to worse glycemic outcomes differ from those reported in the randomized controlled Rabbit 2 and Rabbit 2 Surgery trials. This discrepancy can be partly explained by the fact that BBIR patients displayed worse glycemic baselines. Also, there was no diabetes stewardship team to monitor BG and modify insulin therapy, which is relevant since achieving euglycemia in BBIR patients requires more dose adjustments. This study highlights challenges with standard inpatient glycemic management and calls for further research assessing the benefits of pharmacist-led diabetes stewardship.