Bariatric Surgery: Life Extending

Does bariatric surgery prolong life? Past research has shown that this surgery initiates sustainable weight loss, sends type 2 diabetes into remission, and reduces cardiovascular disease. A study that appears in the January 2015 issue of JAMA compares patients who underwent elective bariatric surgery with obese people who did not. It documents mortality rates at 5 and 10 years after surgery, finding patients who chose bariatric surgery cut their likelihood of death in half.

This retrospective cohort study (N=2500) drew from a veterans database and included a larger proportion of men than earlier studies of mortality had. Approximately 74% of the participants were men with an average age of around 53 at time of surgery. Average BMI was 46. Participants had bariatric surgery between 2000 and 2011. A matched control group of 7,115 veterans was established, creating a 3:1 match. The researchers followed participants for up to 14 years.

At 5 years, 10.4% of participants in the control group had died, while 6.4% of surgical patients died. At 10 years, 23.9% of participants in the control group had died, compared to 13.8% in the surgery group.

The researchers looked at subgroups of patients with diabetes, by gender, and by surgery type. Mortality remained lower in patients who had bariatric surgery with one exception. Earlier bariatric patients were more likely to die in the surgical suite or in the first year after surgery than more recent bariatric cases. The researchers indicate that with time, surgical technique clearly advanced and improved.

This study raises additional research questions, and the researchers plan to re-examine the data in coming years. The fact that most bariatric surgery participants self-select confounds the findings, and the study looked only at mortality and ignored morbidity.

More than 15% of the US adult population has a BMI of 35 or higher, with more than 6% severely obese (BMI ≥40).