Metabolic Surgery for Metabolic Syndrome

Metabolic syndrome (MetS) is a combination of obesity, high blood pressure, abnormal blood sugar, and lipid disorders. It greatly increases the risk of heart disease, stroke, and type 2 diabetes. In Asian populations, MetS often appears at lower body mass index (BMI) levels than in Western countries, making it a growing public health concern even among individuals without severe obesity.

Bariatric surgery has been proven to help patients lose weight and improve blood sugar, blood pressure, and cholesterol levels. However, most studies have been done in patients with severe obesity. There is limited real-world evidence on how surgery affects patients with MetS at lower BMI levels, especially over the long term. In addition, the short-term biological changes that occur immediately after surgery are not fully understood.

This study is a multicenter prospective cohort including patients who had bariatric surgery in three hospitals in China. Patients are being followed for up to 10 years after surgery.

• Early phase: From postoperative day 1 to 7, changes in blood pressure, glucose, and electrolytes are monitored to capture immediate metabolic effects.
• Long-term phase: Follow-up at 3 months, 6 months, 1 year, 5 years, and 10 years is used to assess sustained improvements in weight, blood pressure, glucose, and lipid profiles.

The primary outcome is improvement or resolution of MetS, defined by standardized criteria including BMI, blood pressure, fasting glucose, and lipid levels. Secondary outcomes include changes in individual risk factors, reduction in medication use, and the proportion of patients free of MetS over time.

By providing both short-term and long-term data, this study will clarify how bariatric surgery affects the full course of MetS. The results will help identify patients who may benefit most, guide treatment recommendations, and support better prevention of cardiovascular and metabolic diseases in Asian populations.

Inclusion criteria

• (1) aged 18-65 years; (2) scheduled to undergo bariatric surgery, including laparoscopic Roux-en-Y gastric bypass (LRYGB) or laparoscopic sleeve gastrectomy (LSG); and (3) met the guideline-based indications for surgery at the time of operation.

Exclusion criteria

• (1) coexisting cardiac insufficiency or renal dysfunction; (2) contraindications to bariatric surgery or anesthesia; and (3) refusal to provide informed consent.