Long-term weight loss and metabolic benefit from Roux-en-Y gastric bypass in patients with superobesity

BACKGROUND: Although Roux-en-Y gastric bypass (RYGB) is widely performed worldwide, its efficacy in patients with a body mass index (BMI) greater than 50 kg/m2 remains controversial. The aim of the present paper was to assess long-term (10 years or more) weight loss and metabolic results of RYGB in patients with superobesity (SO; BMI > 50 kg/m2), compared with patients with morbid obesity (MO; BMI 35-50 kg/m2). METHODS: This study involved retrospective analysis of a prospectively followed cohort of adult patients operated on for a primary RYGB between 1999 and 2008. Long-term weight loss and metabolic parameters were compared between SO and MO patients, with a sex-specific subgroup analysis in SO patients. Multiple logistic regression assessed independent predictors of poor long-term weight loss. RESULTS: Among the 957 included patients, 193 (20.2 per cent) were SO (mean BMI 55.3 kg/m2versus 43.3 kg/m2 in MO). Upon 10-year follow-up, which was complete in 86.3 per cent of patients, BMI remained higher in SO patients (mean 39.1 kg/m2versus 30.8 kg/m2, P < 0.001) although total bodyweight loss (per cent TBWL) was similar (28.3 per cent versus 28.8 per cent, P = 0.644). Male SO patients had a trend to higher 10-year per cent TBWL, while initial BMI greater than 50 kg/m2 and low 5-year per cent TBWL were independent predictors of long-term TBWL less than 20 per cent. Diabetes remission was observed in 39 per cent SO and 40.9 per cent MO patients (P = 0.335) at 10 years, and all patients had a significant lipid profile improvement. CONCLUSION: Substantial improvement in co-morbidities was observed in all patients 10 years after RYGB. Total weight loss was similar in SO and MO patients, leaving SO patients with higher BMI. Suboptimal TBWL 5 years after surgery in SO, especially female patients, may warrant prompt reassessment to improve long-term outcomes.