Risk factors associated with mortality after Roux-en-Y gastric bypass surgery.

objectiveWe sought to identify the major risk factors associated with mortality in Roux-en-Y gastric bypass (RYGB) surgery.

backgroundBariatric surgery has become an established treatment for extreme obesity. Bariatric surgery mortality has steadily declined with current rates of less than 0.5%. However, significant variation in the mortality rates has been reported for specific patient cohorts and among bariatric centers.

methodsClinical outcome data from 185,315 bariatric surgery patients from the Bariatric Outcome Longitudinal Database were reviewed. Of these, 157,559 patients had either documented 30 or more day follow-up data, including mortality. Multiple demographic, socioeconomic, and clinical factors were analyzed by univariate analysis for their association with 30-day mortality after gastric bypass. Variables found to be significant were entered into a multiple logistic regression model to identify factors independently associated with 30-day mortality. On the basis of these results, a RYGB mortality risk score was developed.

resultsThe overall 30-day mortality rate for the entire bariatric surgery cohort was 0.1%. Of the 81,751 RYGB patients, the mortality rate was 0.15%. Factors significantly associated with 30-day gastric bypass mortality included increasing body mass index (BMI) (P<0.0001), increasing age (P<0.005), male gender (P<0.001), pulmonary hypertension (P<0.0001), congestive heart failure (P=0.0008), and liver disease (P=0.038). When the RYGB risk score was applied, a significant trend (P<0.0001) between increasing risk score and mortality rate is found.

conclusionsIncreasing BMI, increasing age, male gender, pulmonary hypertension, congestive heart failure, and liver disease are risk factors for 30-day mortality after RYGB. The RYGB risk score can be used to determine patients at greater risk for mortality after RYGB surgery.