The Effect of Loss of Excess Weight on the Metabolic Risk Factors after Bariatric Surgery in Morbidly and Super-Obese Patients

BACKGROUND: Changes in metabolic risk factors such as dyslipidemia and hyperinsulinemia as well as levels of sex hormones and leptin were studied in morbidly obese (MO) and super-obese (SO) patients during excess weight loss (EWL), separately in males and females. METHODS: In this prospective clinical intervention study, 431 patients were included (361 females and 70 males). There were 217 patients with MO (BMI 40-49.9 kg/m2) and 214 patients with SO (BMI > or =50 kg/m2). All patients underwent restrictive bariatric operations. Metabolic parameters (lipids, insulin, leptin, hepatic transaminases, uric acid, and sex hormones) were measured before obesity surgery and at defined postoperative points of EWL (25%, 50%, 75% and 100%). RESULTS: Successful weight reduction of 25% EWL was achieved by 94% of patients at 2 months. With this moderate EWL, most of the patients already improved their risk profile considerably, including normalization of insulin levels. Additional EWL led to a further amelioration of risk profile in all patients, including normalization of triglyceride levels. Male MO and SO patients had a worse metabolic situation preoperatively and a greater benefit after weight loss. Even though SO patients did not lose as much excess weight as MO patients, they did profit comparably. CONCLUSION: Bariatric surgery is a valuable tool not only to reduce excess weight in severely obese patients but also to improve the metabolic risk profile within a short time-frame. This benefit is most pronounced in high-risk males.