Background

Obesity and metabolic syndrome are associated with an increased rate in major adverse cardiovascular events (MACE). Bariatric surgery is the most effective treatment for obesity and related conditions including metabolic syndrome.

Methods

In a population-based cohort study, we compared all morbidly obese patients with metabolic syndrome (diabetes and/or hypertension) who underwent bariatric surgery in Quebec, Canada during 2007 and 2012 with obese controls matched on age, sex, geography and comorbidity burden (Charlson comorbidity index). The incidence of MACE (myocardial infarct, stroke, all-cause mortality) and all-cause mortality at 5 years were compared between both groups. Cox proportional hazard regression was also used to compare the effect of surgery and other variables with respect to outcomes.

Results

3,627 surgical patients met inclusion criteria and were matched to 5,420 obese controls. Baseline demographics were comparable between groups, but diabetes was more prevalent among the surgery group. There was a significant difference in MACE at 5 years between the surgical group and obese controls (17% vs 22% respectively; p<0.01). A significant difference in all-cause mortality was also present between both groups (2.2% vs 3.9% respectively; p<0.01). Bariatric surgery was independently associated with decreased all-cause mortality (HR 0.78 [0.68-0.89]) after adjusting for age, sex and comorbidities.

Conclusions

Bariatric surgery is associated with a decrease in MACE and all-cause mortality in obese patients with metabolic syndrome long term after surgery.