Remission and Relapse Patterns of Type-II Diabetes Mellitus After Bariatric Surgery: A Retrospective Study at a Tertiary Care Center

Background: Type-II diabetes mellitus (T2DM) is commonly associated with obesity and is generally treated with long-term medications. Bariatric surgery has demonstrated positive metabolic outcomes, including glycemic improvement and decreased use of antidiabetic medications. Remission can, however, not be permanent, and relapse of diabetes can occur in the follow-up period. Objective: To assess T2DM remission, relapse, and postoperative glycemic outcomes after bariatric surgery in patients with obesity. Methods: This retrospective observational study was conducted at the General Surgery Department, Hayatabad Medical Complex, Peshawar, Pakistan, between September 2022 and August 2025. A total of 93 patients who presented with obesity were included. The data on demographic characteristics, BMI, glycemic parameters, the use of antidiabetic medications, remission, and relapse were obtained from the hospital records. Follow-up was defined as the time from bariatric surgery to the last available postoperative clinic visit or laboratory assessment. Complete diabetes remission was defined as HbA1c <6.5% maintained for at least three months without glucose-lowering medication. Results: The average age was 43.6 ± 9.8 years. The mean BMI was 44.2 ± 5.9 kg/m² prior to surgery and 33.1 ± 5.2 kg/m² at the most recent follow-up. The average HbA1c dropped to 6.4 ± 0.9% from 8.3 ± 1.4%, while fasting blood glucose decreased from 176.8 ± 42.5 mg/dL to 121.6 ± 28.4 mg/dL. A total diabetes remission was reached in 56 patients (60.2%), and partial improvement of glycemic levels in 21 patients (22.6%). Conclusion: Bariatric surgery was associated with significant improvement in glycemic control, reduction in BMI, and decreased requirement for antidiabetic medications during available follow-up. Although a substantial proportion of patients achieved diabetes remission, relapse was observed in some cases, highlighting the need for long-term metabolic monitoring.