Exocrine Pancreatic Insufficiency after Roux-en-Y gastric bypass

Abstract

Background: Gastric resection, short bowel syndrome, and diabetes mellitus are risk factors for development of exocrine pancreatic insufficiency (EPI). Reasons are multifactorial and not completely elucidated.

Objectives: To determine the prevalence of EPI after distal (dRYGB) and proximal Roux-en-Y gastric bypass (pRYGB) and to assess the influence of respective limb lengths.

Setting: University hospital, Switzerland.

Methods: The study comprised 188 consecutive patients who underwent primary dRYGB (common channel<120 cm, biliopancreatic limb 80-100 cm) or pRYGB (alimentary limb = 155 cm, biliopancreatic limb 40-75 cm) and who were followed-up for at least 2 years. Patients with a history of gastrointestinal or hepatobiliary resection (except for cholecystectomy), postoperative pregnancy, and any revision of RYGB (gastric pouch, limb lengths) were excluded. EPI was defined by clinical symptoms in combination with fecal pancreatic elastase-1<200 μg/g stool or fecal pancreatic elastase-1>200 and<500 μg/g stool and positive dechallenge-rechallenge test with pancreatic enzyme replacement therapy.

Results: Mean follow-up was 52.2 months (range 24-120). Seventy-nine patients (42%) underwent dRYGB, and 109 (58%) underwent pRYGB. Of those, 59 (31%) patients were diagnosed with EPI after a mean 12.5±16.3 months. There was a significant difference between dRYGB and pRYGB groups in initial body mass index (dRYGB 47.1±8.1 kg/m(2) versus pRYGB 42.7±6.1 kg/m(2); P<.01), patients in Obesity Surgery Mortality Risk Score group C (13% versus 3%; P = .02), and prevalence of EPI (48% versus 19%; P<.01). Neither overall small bowel length nor absolute or relative limb lengths were influencing factors on EPI after dRYGB.

Conclusion: Prevalence of EPI after dRYGB (48%) and pRYGB (19%) is of clinical importance. There was no significant difference in absolute or relative limb lengths between EPI and non-EPI groups after dRYGB.

Keywords: Bariatric surgery; Diarrhea; Exocrine pancreatic insufficiency; Limb lengths; Postcibal asynchrony; Roux-en-Y gastric bypass; Steatorrhea.