Association Between the Relative Duration of Sliding Scale Insulin Use and the Length of Hospital Stay in Non-Critically Ill Patients with Type 2 Diabetes.

Objective To examine the association between the proportion of hospitalizations managed with sliding-scale insulin and inpatient outcomes in non-critically ill patients with type 2 diabetes mellitus. Patients and Methods We conducted a retrospective cohort study of 595 hospitalized patients with previously diagnosed type 2 diabetes mellitus who initially received sliding-scale insulin (SSI) for glycemic management and were subsequently transitioned to scheduled insulin therapy prior to discharge. The primary outcome was the length of hospital stay (LOS), and the secondary outcomes included intensive care unit (ICU) transfer and in-hospital mortality. The nonlinearity between the SSI/LOS and outcomes was assessed using quadratic regression. Based on the identified inflection point, patients were stratified into SSI/LOS ≤50% and SSI/LOS >50% groups. Results SSI/LOS demonstrated a non-linear, U-shaped association with the length of stay, with the shortest length of stay observed at 47% (adjusted R2=0.408). Both the lower and higher SSI/LOS values were associated with longer hospitalizations. The results were robust to adjustments for glycemic variability and sensitivity analysis using the absolute SSI duration. Conclusion Relative SSI exposure during hospitalization was nonlinearly associated with LOS. Inpatient insulin management patterns, rather than SSI use alone, may be associated with the hospital course.