Bariatric Surgery to Reduce Mortality in US Adults. A Public Health Perspective from the Analysis of the American National Health and Nutrition Examination Survey Linked to the US Mortality Register

Background: Type II obesity represents a major pandemic and public health threat in high-income countries. Type II obesity increases the risk of all-cause and specific-cause mortality, and it is widely acknowledged that bariatric surgery represents the only effective therapeutic option in these patients. The aim of the present study was to estimate US population attributable risk for all-cause and cause-specific mortality in type II obese subjects undergoing weight loss as resulting from bariatric surgery alone and supplemented with behavioral intervention. Methods: The American National Health and Nutrition Examination Survey linked to the US death registry updated to 2011 was used to estimate type II obesity prevalence and all-cause and specific cause of death for type II obese adults undergoing weight loss. Multivariate adjusted proportional hazard Cox models were used to estimate mortality risks. Statistical analyses were performed on the most updated version of the database (June 2017). Results: A monotone positive trend for type II obesity was observed during the period 1999–2014 (p < 0.001). According to trend analysis, the rate of type II obesity in US adults is expected to rise up to 8.5%. Two- to sevenfold increased risk of all-cause and specific-cause mortality was observed for type II obese participants when compared to type I obese and overweight participants. Population attributable risk for all-cause and specific-cause mortality for type II obese subjects undergoing weight loss was ranging between 6 and 34%. Conclusions: Bariatric surgery supplemented with behavioral intervention can result in a relevant reduction of mortality if extensively applied to the US population.