Longitudinal Follow-Up of Roux-en-Y Gastric Bypass Patients after Evaluation of Abdominal Pain: 2010 ACG/AstraZeneca Fellow Award

Abstract

Purpose: Abdominal pain is a common and potentially challenging patient symptom. In the USA, Roux-en-Y gastric bypass (RYGB) is the most common surgical procedure for medically-complicated obesity. The purpose of this study is to determine the diagnostic stability after evaluation of abdominal pain in RYGB patients. Methods: This is a prospective, cohort study performed in an urban community hospital. Consecutive RYGB patients (n=147 patients) seen at a new joint Medical/Surgical Bariatric Clinic from February 1, 2008 to January 31, 2009 were included. Chief complaint and the location of abdominal pain were recorded. Information collected included date of surgery, duration of symptom, weight loss after surgery, smoking status, and the use of an NSAID/aspirin. Baseline demographics (i.e. age, sex and body mass index) were also recorded. In diagnostic evaluation, 25 patients underwent glucose hydrogen breath testing (GHBT), 19 completed upper endoscopy, 8 received empiric trials of metronidazole, and 4 underwent CT scan of the abdomen. Whole blood thiamine levels were measured in all patients. Reexamination of patients who were evaluated for abdominal pain was performed 1 year after completion of the patients' initial evaluation (up to May 2010). Results: Forty-nine out of 147 patients reported a chief complaint of abdominal pain (prevalence: 33%). Duration of abdominal pain ranged from 1 week to 7 years (median: 6 months). Following an initial evaluation, a diagnosis was established in 38 of 49 patients (77%). These diagnoses included: small intestinal bacterial overgrowth (SIBO; n=25), thiamine deficiency (n=5), marginal ulceration at the site of the gastrojejunal anastomosis (n=3), cholecystitis (n=2), and partial small intestinal obstruction (n=1). One patient obtained prolonged pain relief after a nerve block for abdominal wall pain. Appropriate treatment was initiated based upon the initial diagnosis. During a 1 year follow-up period, 1 additional patient (2%) received relief of abdominal pain following cholecystectomy, 42 (85%) reported improvement in their abdominal pain, while 2 patients did not follow-up. Conclusion: This study demonstrates that abdominal pain is common after RYGB. In our RYGB patients, SIBO (diagnosed by abnormal GHBT) is the most common cause for chronic abdominal pain. The majority of RYGB patients obtain improvement in their abdominal pain after diagnosis and treatment. This study also demonstrates that after an appropriate initial evaluation, in a 1 year follow up, an additional origin for abdominal pain was identified in only 2% of patients after RYGB.