A Comparison of Inpatient Cost Per Day in General Surgery Patients with Type 2 Diabetes Treated with Basal-Bolus versus Sliding Scale Insulin Regimens

BACKGROUND: The identification of cost-effective glycaemic management strategies is critical to hospitals. Treatment with a basal-bolus insulin (BBI) regimen has been shown to result in better glycaemic control and fewer complications than sliding scale regular insulin (SSI) in general surgery patients with type 2 diabetes mellitus (T2DM), but the effect on costs is unknown. OBJECTIVE: We conducted a post hoc analysis of the RABBIT Surgery trial to examine whether total inpatient costs per day for general surgery patients with T2DM treated with BBI (n = 103) differed from those for patients with T2DM treated with SSI (n = 99) regimens. METHODS: Data were collected from patient clinical and hospital billing records. Charges were adjusted to reflect hospital costs. General linearized models were used to estimate the risk-adjusted effects of BBI versus SSI treatment on average total inpatient costs per day. RESULTS: Risk-adjusted average total inpatient costs per day were $US5404. Treatment with BBI compared with SSI reduced average total inpatient costs per day by $US751 (14%; 95% confidence interval [CI] 20–4). Being treated in a university medical centre, being African American or having a bowel procedure or higher-volume pharmacy use significantly reduced costs per day. CONCLUSIONS: In general surgery patients with T2DM, a BBI regimen significantly reduced average total hospital costs per day compared with an SSI regimen. BBI has been shown to improve outcomes in a randomized controlled trial. Those results, combined with our findings regarding savings, suggest that hospitals should consider adopting BBI regimens in patients with T2DM undergoing surgery.