Outcome of biliopancreatic diversion in subjects with Prader-Willi syndrome

Background: In Prader-Willi Syndrome (PWS), mental retardation and compulsive hyperphagia cause early obesity, the co-morbidities of which lead to short life-expectancy, with death usually occurring in their 20s. Long-term weight loss is mandatory to lengthen the survival; therefore, the lack of compliance in voluntary food restriction requires a surgical malabsorptive approach. Methods: 15 PWS subjects were submitted to biliopancreatic diversion (BPD) and followed (100%) for a mean period of 8.5 (4-13) years. BPD consists of a distal gastrectomy with a long Roux-en-Y reconstruction which, by delaying the meeting between food and biliopancreatic juices, causes an intestinal malabsorption. Indication for BPD was BMI >40 or >35 with metabolic complications. Preoperative mean age was 21±5 years, mean weight 127±26 kg, and mean Body Mass Index (BMI, kg/m²) 53±10. According to Holm's criteria, all of the subjects had a total score ≥8. IQ assessment was performed in each subject, with a mean score of 72±10. An arbitrary lifestyle score was given to each subject. Results: No perioperative complications were observed. Percent excess weight loss (%EWL) was 59±15 at 2 years and 56±16 at 3 years, and then progressive regain occurred; at 5 years %EWL was 46±22 and at 10 years 40±27. Spearman rank test failed to demonstrate any correlation between weight loss at 5 years and patient data, except with lifestyle score (Spearman r=0.8548, p