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

Abstract

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.

Fig. 1

Weight evolution of patients with morbid obesity versus superobesity during the 10-year follow-up a BMI values. b Excess BMI loss (EBMIL per cent). c Total bodyweight loss (TBWL per cent). All variables are represented by mean values in each time point. An asterisk (*) indicates significant a difference between MO and SO patients. SO, superobesity; MO, morbid obesity; BMI, body mass index.

Fig. 2

Metabolic profile evolution of patients with morbid obesity versus superobesity during the 10-year follow-up a Fasting glycaemia values (mol/l). b Total cholesterol (mmol/l). c High-density lipoprotein (HDL) cholesterol (mmol/l). d Ratio total/HDL cholesterol. e Low-density lipoprotein (LDL) cholesterol (mmol/l). f Triglycerides (mmol/l). g Urates (mmol/l). All variables are represented by mean values. An asterisk (*) indicates significant a difference between MO and SO patients. SO, superobesity; MO, morbid obesity.

Fig. 3

Weight evolution of male versus female patients with superobesity during the 10-year follow-up a BMI values. b Excess BMI loss (EBMIL per cent). c Total bodyweight loss (TBWL per cent). All variables are represented by mean values in each time point. An asterisk (*) indicates significant a difference between male and female patients. M, male; F, female; BMI, body mass index.