Bariatric surgery associated with reduced risk for dying over the long-term, especially for older patients

A study of more than 26,000 patients found that bariatric surgery is associated with a lower risk for dying over the long-term, especially for heavier patients and those who have weight loss surgery at older ages. The results are published in Annals of Internal Medicine.

Researchers from McMaster University and St. Joseph's Healthcare Hamilton, Ontario, Canada studied more than 13,000 adults with moderate to severe obesity who had weight loss surgery and a matched cohort of more than 13,000 patients who were eligible for surgery but did not have it from 2010 to 2016 in Ontario to compare the risk for dying over the long term between the two groups. They also examined whether the age, gender, and BMI at the time of surgery had any impact on survival.

After a median follow-up of almost 5 years, the researchers found that the overall mortality rate was 1.4 percent in the surgery group and 2.5 percent in the nonsurgery group, with a lower adjusted hazard ratio of all-cause mortality (HR, 0.68 [95% CI, 0.57 to 0.81]). The difference in mortality risk was substantial among older adults and those who were more obese when they had bariatric surgery. After measurable differences between patients who had surgery and those who didn't were accounted for, patients aged 55 years or older had a 48 percent lower risk for dying than matched patients who didn't have surgery. Meanwhile, men and women derived essentially equal benefits. According to the researchers, their study provides one of the most complete pictures of the association between bariatric surgery and mortality by delineating the specific effects among several important patient subgroups.