836-P: Models to Predict Initial Insulin Requirements in Hospitalized Patients with Diabetes

Background: The quality of inpatient glycemic control is limited by unknown starting dose of insulin at hospital admission.

Aim: To evaluate and estimate the first day insulin dose requirement in hospitalized patients with diabetes mellitus.

Methods: In this retrospective cohort study, patients with previous history of diabetes mellitus, aged ≥ 18 years, and admitted to UC Davis Medical Center from January 1, 2017 to December 31, 2018 were randomly recruited. Independent factors that may affect the insulin requirement were collected. The dependent factor is corrected insulin total daily dose (CxTDD) during the first 24 hours of hospitalization, which is defined as the insulin dose actually given plus calculated correction dose to target average blood glucose 180 mg/dL. Multivariable regression analyses are used to build models to predict CxTDD.

Results: The 144 patients who were prescribed insulin before admission had higher average blood glucose and higher CxTDD during the first 24 hours of hospitalization, compared to the 97 patients who were not prescribed insulin before admission (median 201.7 vs. 171 mg/dL, 25 vs. 5 units, respectively]. The adjusted R squares of the multivariable regression models are 58.6% in patients who were on insulin before admission, and 35.5% in those who were not, with common significant independent factors including first blood glucose upon presentation, body weight, oral intake, and new glucocorticoid use. Opiate/IV pain medication and home insulin daily dose are significant predictive factors (SIRS shows trend toward significance) only in patients who were prescribed insulin before admission.

Conclusion: Models to predict the first day insulin dose requirement shows clear differences between patients who were prescribed insulin versus not prescribed insulin before admission. First blood glucose upon presentation is a strong predictor of first day insulin dose requirement after hospitalization and this has not been emphasized previously in the literature.