Abstract
INTRODUCTION: Basal and intermediate insulin is available as U-100 (glargine, determir, NPH) or ultra-long-acting (ULA) U-200 (degludec) or U-300 (glargine). Insulins may be substituted with other insulin formulations based on financial factors, formulary preferences, patient preference, and patient response. OBJECTIVE: Evaluate the impact on total daily dose of insulin when switching from an intermediate or basal U-100 to a ULA insulin. METHODS: A single-center retrospective chart review was performed at a federally qualified health center. Patients switched from a U-100 intermediate or basal insulin to a U-200 degludec or U-300 glargine ULA insulin from 2019 to March 2024 were assessed. Clinical measures assessed were initial intermediate or basal insulin total daily dose, ULA insulin total daily dose at time of switch, at 1, 3, and 6 months, and change in HgbA1c, BMI, and weight. RESULTS: When switched from a U-100 to a U-200 or U-300 insulin (n = 53), basal insulin total daily dose decreased by 13.1 units at 6 months (P < .05). At the 6-month mark after ULA switch, HgbA1c decreased (P < .001), but BMI (P = .161) and weight (P = .076) were similar. HgbA1c, BMI, weight, and total daily insulin dose were not significantly different between patients assigned U-200 and U-300 insulins. CONCLUSION: Patients switched from a U-100 basal insulin may utilize a lower total daily dose of a ULA insulin and experience reductions in HgbA1c, BMI, and weight.