Bariatric Surgery Does Not Decrease Mortality Rate of Older Males

There has been an obesity epidemic in the United States and in other parts of the world.  Obesity is a difficult condition to treat, but bariatric surgery has been shown to be the most effective way to induce weight loss in the severely obese.  Bariatric surgery has been shown to decrease mortality in patients who undergo the procedure.  These studies have primarily investigated the mortality rates of younger, white, mostly female patients after bariatric surgery.  Researchers headed by Dr. Matthew Maciejewski wanted to examine if there was a mortality benefit for older men.  The results of their study were published online in the Journal of the American Medical Association.  Mortality rates for older men who had gone through bariatric surgery were investigated at 12 Veterans Affairs medical centers.  The researchers used a retrospective cohort study involving 850 veterans who had bariatric surgery from January 2000 to December 2006 and compared mortality to 41,244 individuals who did not have the surgery.  The study participants were followed by the investigators for a mean of 6.7 years up to December of 2008.  The main outcome that was measured was all cause mortality.  The surgical study participants had an average age of 49.5 and a mean body mass index (BMI) of 47.4, while the nonsurgical study participants had an average age of 54.7 and a BMI of 42.0.  The bariatric surgery patients had a mortality rate of 1.5%, 2.2%, and 6.8% at 1, 2, and 6 year after surgery, respectively.  The nonsurgical patients had mortality rates of 2.2%, 4.6%, 15.2% at 1, 2, and 6 year time intervals, respectively.  After adjustment for variables, bariatric surgery remained associated with reduced mortality.  After further statistical analysis of 1694 propensity-matched patients, bariatric surgery was no longer associated with reduced mortality in older veteran men.  The authors wrote “In propensity score–adjusted analyses of older severely obese patients with high baseline mortality in Veterans Affairs medical centers, the use of bariatric surgery compared with usual care was not associated with decreased mortality…”.  These results are in conflict with previous studies that have shown a mortality advantage for patients who undergo bariatric surgery.  Some of the differences can be explained by the patient populations that were examined, the time of follow up, and the statistical analysis of variable factors such as comorbidities.  The investigators noted that previous studies examined a younger predominantly female patient population.  Finally, the authors wrote “Even though bariatric surgery is not associated with reduced mortality among older male patients, many patients may still choose to undergo bariatric surgery, given the strong evidence for significant reductions in body weight and comorbidities and improved quality of life”.

Reference:

Maciejewski ML, et al. “Survival Among High-Risk Patients After Bariatric Surgery” JAMA published online first.  June 12, 2011. doi:10.1001/jama.2011.817

Tagged as: bariatric surgery, Dr. Matthew Maciejewski, mortality rate, obesity