Major Finding: Gastric bypass provided no survival benefit to older, obese patients followed for a mean of 6.7 years after their operations, when compared to propensity-matched controls (HR, 0.83; 95% CI, 0.61-1.14).
Data Source: Retrospective cohort study of 850 participants in a Veterans Affairs Study who had bariatric surgery in 2000-2006 and 41,244 nonsurgical controls.
Disclosures: Dr Maciejewski is a paid consultant to Takeda Pharmaceuticals and Novartis and owns stock in Amgen. Dr. Livingston is a paid consultant to Texas Instruments.
SEATTLE – Gastric bypass did not extend the lives of older, severely obese patients in a Department of Veterans Affairs Study.
Though bariatric surgery is often assumed to extend lives, “physicians should advise patients such as those examined here that there is no survival benefit at nearly 7 years, and the longer-term survival benefit is still unknown,” lead author Matthew L. Maciejewski, Ph.D., of Duke University and the Center for Health Services Research in Primary Care at the Durham VA Medical Center said at the meeting.
He and his colleagues compared 850 VA Roux-en-Y gastric bypass patients with 41,244 nonsurgical controls. The operations were conducted between 2000 and 2006. The average age in the bypass group was 50 years and average body mass index was 47 kg/m
At first glance, bypass patients appeared to do better after a mean follow-up of 6.7 years. Although 6.8% had died after 6 years, for instance, 15.2% had died in the control group (hazard ratio, 0.64; 95% confidence interval, 0.51-0.80).
The apparent advantage, however, diminished after covariate adjustment (HR, 0.80; 95% CI, 0.63-0.99), and vanished when patients were propensity matched one to one with the most similar controls based on age, sex, race, marital status, BMI, diagnosis related groups (DRG), and other factors (HR, 0.83; 95% CI, 0.61-1.14). When the investigators further adjusted for the start time, the advantage disappeared (HR, 0.94, 95% CI, 0.64-1.39).
In short, “the use of bariatric surgery, compared with usual care, was not associated with decreased mortality,” Dr. Maciejewski and his colleagues concluded (JAMA 2011 [doi:10.1001/jama.2011.817]).
The results mean “you should not select people [for surgery] thinking they are going to live longer,” said coauthor Dr. Edward Livingston, chair of the GI and endocrine surgery division at the University of Texas Southwestern Medical School at Dallas.
Selection instead should be based on immediate concerns. Out-of-control diabetes, a patient too big to get around, sleep apnea, failing joints, and other weight-related problems make “surgery a reasonable option,” said Dr. Livingston.
The findings contradict previous studies suggesting a survival benefit for bariatric surgery, but those studies were largely of younger women with inherently lower obesity-related mortality risks, or foreign studies that don't translate well to the United States, he said.
In contrast, the veterans in the study – older, obese, and comorbid – “die at a very high rate, so we expected [surgery to show] a big benefit in a short amount of time. The belief is if you take people that are really sick with diabetes, hypertension, and sleep apnea, and get a lot of weight off them, they live longer. We didn't see it.”