Association between metabolic surgery and cardiovascular outcome in patients with hypertension : A nationwide matched cohort study

Background Hypertension, together with obesity, is a leading cause of mortality and disability. Whilst metabolic surgery offers remission of several metabolic comorbidities, the effect for patients with hypertension remains controversial. The objective of the present study was to evaluate the effect of metabolic surgery on cardiovascular events and mortality on patients with morbid obesity (body mass index [BMI] >= 35 kg/m(2)) and hypertension. Methods and findings We conducted a matched cohort study of 11,863 patients with morbid obesity and pharmacologically treated hypertension operated on with metabolic surgery and a matched non-operated-on control group of 26,199 subjects with hypertension (matched by age, sex, and area of residence) of varied matching ratios from 1:1 to 1:9, using data from the Scandinavian Obesity Surgery Register (SOReg), the Swedish National Patient Registers (NPR) for in-hospital and outpatient care, the Swedish Prescribed Drug Register, and Statistics Sweden. The main outcome was major adverse cardiovascular event (MACE), defined as first occurrence of acute coronary syndrome (ACS) event, cerebrovascular event, fatal cardiovascular event, or unattended sudden cardiac death. The mean age in the study group was 52.1 +/- 7.46 years, with 65.8% being women (n = 7,810), and mean BMI was 41.9 +/- 5.43 kg/m(2). MACEs occurred in 379 operated-on patients (3.2%) and 1,125 subjects in the control group (4.5%). After adjustment for duration of hypertension, comorbidities, and education, a reduction in risk was seen in the metabolic surgery group (adjusted hazard ratio [HR] 0.73, 95% confidence intervals [CIs] 0.64-0.84, P < 0.001). The surgery group had lower risk for ACS events (adjusted HR 0.52, 95% CI 0.41-0.66, P < 0.001) and a tendency towards lower risk for cerebrovascular events (adjusted HR 0.81, 95% CI 0.63-1.01, P = 0.060) compared with controls. The main limitations with the study were the lack of information on BMI and history of smoking in the control group and the nonrandomised study design. Conclusion Metabolic surgery on patients with morbid obesity and pharmacologically treated hypertension was associated with lower risk for MACEs and all-cause mortality compared with age- and sex-matched controls with hypertension from the general population. Author summaryWhy was this study done? Hypertension, particularly in combination with morbid obesity, is a leading cause of mortality and disability worldwide. There is compelling evidence that metabolic surgery on patients with type 2 diabetes and morbid obesity leads to reduced risk for acute cardiovascular events, but the effect on patients with hypertension and morbid obesity remains unclear. The main purpose of this study was to evaluate whether metabolic surgery is associated with altered risk for major adverse cardiovascular events for patients with hypertension and morbid obesity compared with a matched control group from the general population. What did the researchers do and find? The nationwide, register-based study included 11,863 patients and 26,199 controls. Metabolic surgery was associated with reduced risk for major adverse cardiovascular event, in particular acute coronary events. What do these findings mean? This study indicates that metabolic surgery (gastric bypass and sleeve gastrectomy) is associated with reduced risk for major adverse cardiovascular events for patients with hypertension and morbid obesity, suggesting that metabolic surgery should be considered in the treatment of patients with hypertension and morbid obesity