Medical weight loss treatment for obesity with metabolic syndrome: from standard diagnosis to comprehensive intervention

I. Overview of Metabolic Syndrome Obesity, especially abdominal obesity, is associated with insulin resistance and often leads to type 2 diabetes. These factors can also cause hyperglycemia, dyslipidemia, hypertension, and vascular inflammation, promoting the development of atherosclerotic cardiovascular disease (CVD). The simultaneous presence of metabolic risk factors suggests the presence of metabolic syndrome (MS). There are several diagnostic criteria for MS: 1. WHO criteria: including abnormal blood glucose/insulin resistance, plus blood pressure >140/90 mmHg, TG ≥1.7 mmol/L, central obesity (waist-to-hip ratio >0.9 for men, >0.85 for women), or microalbuminuria. 2. NCEP-ATP III: including at least 3 of the following: waist circumference, TG, HDL-c, blood pressure, and fasting blood glucose. 3. International Diabetes Federation (IDF): central obesity is a necessary condition (≥85 cm for Chinese men, ≥80 cm for women), plus 2 or more of the other indicators. Weight gain is a major risk factor for MS; waist circumference alone can identify up to 46% of individuals who will develop MS within 5 years. Consumption of soft drinks and sugary beverages is also associated with an increased risk of MS. II. Medical treatment for MS: First-line treatments for MS are weight loss and increased physical activity.

Lifestyle interventions: (1) Total dietary energy: A negative energy balance must be achieved. A dietary intake of >800 kcal/day is recommended, as very low energy intake may slow the resting metabolic rate. (2) Dietary patterns: The Mediterranean diet group showed significant improvements in weight loss, blood pressure, and blood lipids. The DASH diet improved triglycerides, diastolic blood pressure, and fasting blood glucose even better. Low glycemic index foods are particularly beneficial for MS patients. Patient adherence is the most important predictor of weight loss. (3) Exercise: At least 30 minutes of moderate-intensity exercise daily is recommended. (4) Continuous monitoring: Doctors and nutritionists should conduct regular follow-ups and encourage lifelong improvement.

Drug-induced weight loss: Orlistat reduces fat absorption by inhibiting pancreatic lipase, thus suppressing 25%–30% of energy intake in the form of fat. Side effects are mainly gastrointestinal reactions (oil spots, increased flatulence and bowel movements), and it may reduce the absorption of fat-soluble vitamins; therefore, it is generally recommended to take a multivitamin supplement before bedtime. For patients with type 2 diabetes, hypoglycemic agents that promote weight loss (such as metformin, GLP-1 receptor agonists, and SGLT-2 inhibitors) are preferred. Liraglutide (3.0 mg/day) has been approved for weight loss.

Weight loss surgery: Recommended indications for surgery: ① Ages 18-60, with poorly controlled weight gain despite medical treatment. ② Surgery should be actively pursued for BMI ≥ 32.5 kg/m²; surgery is recommended for those with BMI ≥ 28-32.4 kg/m² who meet the criteria for the additional two MS subgroups; for those with BMI 25-27.4 kg/m², if there is abdominal obesity and comorbidities, the level of surgery may be increased at the discretion of the surgeon.