Effects of Bariatric Surgery in Obese Patients With Hypertension: The GATEWAY Randomized Trial (Gastric Bypass to Treat Obese Patients With Steady Hypertension)

Abstract

Background: Recent research efforts on bariatric surgery have focused on metabolic and diabetes mellitus resolution. Randomized trials designed to assess the impact of bariatric surgery in patients with obesity and hypertension are needed.

Methods: In this randomized, single-center, nonblinded trial, we included patients with hypertension (using ≥2 medications at maximum doses or >2 at moderate doses) and a body mass index between 30.0 and 39.9 kg/m². Patients were randomized to Roux-en-Y gastric bypass plus medical therapy or medical therapy alone. The primary end point was reduction of ≥30% of the total number of antihypertensive medications while maintaining systolic and diastolic blood pressure <140 mm Hg and 90 mm Hg, respectively, at 12 months.

Results: We included 100 patients (70% female, mean age 43.8±9.2 years, mean body mass index 36.9±2.7 kg/m2), and 96% completed follow-up. Reduction of ≥30% of the total number of antihypertensive medications while maintaining controlled blood pressure occurred in 41 of 49 patients from the gastric bypass group (83.7%) compared with 6 of 47 patients (12.8%) from the control group with a rate ratio of 6.6 (95% confidence interval, 3.1-14.0; P<0.001). Remission of hypertension was present in 25 of 49 (51%) and 22 of 48 (45.8%) patients randomized to gastric bypass, considering office and 24-hour ambulatory blood pressure monitoring, respectively, whereas no patient submitted to medical therapy was free of antihypertensive drugs at 12 months. A post hoc analysis for the primary end point considering the SPRINT (Systolic Blood Pressure Intervention Trial) target reached consistent results, with a rate ratio of 3.8 (95% confidence interval, 1.4-10.6; P=0.005). Eleven patients (22.4%) from the gastric bypass group and none in the control group were able to achieve SPRINT levels without antihypertensives. Waist circumference, body mass index, fasting plasma glucose, glycohemoglobin, low-density lipoprotein cholesterol, triglycerides, high-sensitivity C-reactive protein, and 10-year Framingham risk score were lower in the gastric bypass than in the control group.

Conclusions: Bariatric surgery represents an effective strategy for blood pressure control in a broad population of patients with obesity and hypertension.

Clinical trial registration: URL: https://clinicaltrials.gov. Unique identifier: NCT01784848.

Keywords: bariatric surgery; hypertension; obesity.

Figure 1.

Eligibility, randomization, and follow-up.

Figure 2.

Primary end point and medication use. The proportion of patients with reduction of the total number of antihypertensive drugs of ≥30% while keeping the office blood pressures levels controlled. A, The P value for comparing proportions of patients with primary end point was performed using the Fisher exact test. B, The distribution of the number of antihypertensive medications used during the study period and patients with uncontrolled blood pressure (Office BP). CI indicates confidence interval.

Figure 3.

Blood pressure. The mean office blood pressure levels over a 12-month period among patients receiving medical therapy and those who underwent gastric bypass surgery. I bars indicate standard deviation. Mean values in each group are provided below the graphs.

Figure 4.

Proportion of patients who achieved primary end point (bars graphs) and changes in body weight during 12 months (lines graphs). Proportion of patients with reduction of the total antihypertensive drugs of ≥30% while maintaining the office blood pressure levels controlled (bar graph) and change of body weight (line graph). I bars indicate standard deviation.