Insulin Requirements in Patients With Type 2 Diabetes Undergoing Bariatric Surgery in the Inpatient Setting and Upon Discharge: A Single-Center Retrospective Analysis of Insulin Management Strategies.

OBJECTIVE

Rapid improvement in blood glucose (BG) after weight-loss surgery (WLS) can make postoperative glucose management challenging in patients with type 2 diabetes mellitus (T2DM). Our study examined the safety and efficacy of insulin management strategies during hospitalization and after discharge following WLS.

METHODS

This single-center retrospective cohort study included 160 adult patients with type 2 diabetes mellitus undergoing WLS. Patients with glycated hemoglobin A1C (HbA1C) level <7% (53 mmol/mol) and not on antihyperglycemic medications or metformin monotherapy were excluded. BG and insulin dosing during hospitalization and at 2-week follow-up, and impact of preoperative HbA1C level were analyzed.

RESULTS

Mean age was 46.3 years. Median preoperative HbA1C level was 8% (64 mmol/mol). Postoperatively, most patients received basal insulin plus sliding-scale insulin (SSI; 79/160, 49%) or SSI alone (77/160, 48%). The initial postoperative basal dose was 0.23 units/kg/day. The median basal insulin dose at discharge was 61% lower than preoperative dose. At 2-week follow-up, 34 of 44 patients (77%) had BG levels between 70-200 mg/dL and 1 of 44 (2.2%) had BG levels >200 mg/dL, with no hypoglycemia. Patients with HbA1C level >9% (75 mmol/mol) had higher BG on admission and during hospitalization, required higher insulin doses while hospitalized, and were more frequently discharged on insulin.

CONCLUSION

SSI is effective in managing BG in some patients immediately after WLS. However, about half of the patients may require basal insulin at doses similar to those required by other inpatients. Preoperative hyperglycemia may affect inpatient insulin needs and BG. Low-dose basal insulin appears safe and effective upon discharge for select patients.