This article is more than 5 years old. Information may no longer be current.
Bariatric surgery an effective strategy to improve BP control in obese hypertensive patients
Click Here to Manage Email Alerts
ANAHEIM, Calif. — In the GATEWAY study, obese patients with hypertension were able to reduce their use of antihypertensive drugs while maintaining BP control after undergoing bariatric surgery.
“The cardiovascular risk for mortality is almost doubled when associated with obesity and hypertension,” Carlos Aurelio Schiavon, MD, PhD, FACS, from the Heart Hospital – HCor in São Paulo, Brazil, said during a press conference at the American Heart Association Scientific Sessions. “There are also treatment challenges in these patients because they are often taking multiple drugs, which is associated with low adherence.”
Although observational and randomized trials, usually focused on type 2 diabetes, have associated bariatric surgery with a reduction in overall CV events, the effect of the procedure in patients with hypertension remains uncertain, he noted.
Better BP control, fewer medications
For the single-center, nonblinded trial, Schiavon and colleagues randomly assigned 100 patients in a 1:1 fashion to undergo Roux-en-Y gastric bypass plus medical therapy or medical therapy alone, which included lifestyle modification and visits to a cardiologist, a nutritionist and a psychologist. All patients had a BMI ranging from 30 to 39.9 kg/m2 and were taking at least two medications at maximum doses or more than two medications at moderate doses.
Forty-nine patients in the bariatric surgery group and 47 in the medical therapy alone group completed follow-up.
At 1 year, 83.7% of patients who underwent bariatric surgery vs. 12.8% of those who received medical therapy alone achieved the primary endpoint of a 30% or greater reduction in the total number of antihypertensive medications while maintaining BP lower than 140 mm Hg/90 mm Hg. The researchers calculated a rate ratio of 6.6 (95% CI, 3.1-14) for the primary outcome.
Furthermore, 51% of the bariatric surgery group had remission of hypertension as assessed by office BP and 45.8% had remission as assessed by 24-hour ambulatory BP monitoring. However, no patients in the medical therapy alone group had remission.
Results were similar in a sensitivity analysis, Schiavon noted.
In a post hoc analysis using the SPRINT target of systolic BP lower than 120 mm Hg, 32.7% of patients in the bariatric surgery group achieved the primary endpoint, compared with 8.5% in the medical therapy alone group (rate ratio = 3.8; 95% CI, 1.4-10.6). Additionally, 22.4% of the bariatric surgery group, compared with none in the medical therapy alone group, had remission of hypertension.
Improvements in secondary endpoints
In terms of secondary endpoints, 75% of the bariatric surgery group was using one or no antihypertensive drugs, whereas 50% of the medical therapy alone group was using three or more antihypertensive drugs (P < .001) after 1 year, with comparable BP between groups.
Weight loss, components of metabolic syndrome, waist circumference, fasting plasma glucose, triglycerides and inflammatory profile were also significantly improved in the bariatric surgery group vs. the medical therapy alone group, Schiavon noted.
Anemia and hypervitaminosis B12 were more common in the bariatric surgery group, as was rehospitalization.
At baseline, the mean age was 44 years, the mean BMI was 37 kg/m2, the average duration of hypertension was 9.4 years and 70% of patients were women.
The results were simultaneously published in Circulation.
Benefits of bariatric surgery
As expected, weight was significantly greater among patients who underwent gastric bypass, compared with those assigned medical therapy alone, which was likely the main reason for the remission or reduction of medications in that group, according to Schiavon.
“However, most of the patients in the gastric bypass group achieved the primary endpoint in the first month of the postoperative period, so we believe something more is happening with surgery beyond weight loss.
“These results have implications in minimizing nonadherence to therapy and its related consequences. Taken together with the improved metabolic and inflammatory profile, such effects have, in theory, the potential to reduce major cardiovascular events,” Schiavon said. – by Melissa Foster
References:
Schiavon CA. LBS.03 – Latest Insights into Hypertension Management. Presented at: American Heart Association Scientific Sessions; Nov. 11-15, 2017; Anaheim, California.
Schiavon CA, et al. Circulation. 2017;doi:10.1161/CIRCULATIONAHA.117.032130.
Disclosure: The study was supported by Ethicon Inc. Schiavon reports he has received a research grant from and is on the speakers bureau for Johnson & Johnson Brazil.
Perspective
Back to Top
Paul Poirier, MD, PhD, FRCPC, FCCS, FACC, FAHA
This is one of the biggest trials, in terms of randomization, evaluating bariatric surgery.
The study population, which primarily included women and younger patients with a BMI slightly greater than 35 kg/m2, is what we’re accustomed to seeing in bariatric surgery trials. It is worth noting, however, that these patients do not fulfill criteria for bariatric surgery, which is indicated for patients with a BMI of at least 40 kg/m2 or a BMI of 35 kg/m2 or greater with at least one obesity-related comorbidity.
We know from other studies that bariatric surgery is associated with improved weight loss, inflammation, metabolic profile, CV performance and CV comorbidity remission. However, most of the data on hypertension are reported from studies designed for a different endpoint and are often restricted to patients with diabetes or they are data from observational studies. This study, which is the first to evaluate BP in hypertension as a primary endpoint, showed that patients randomized to gastric bypass were six times more likely to reduce at least 30% of the total number of antihypertensive medications.
This trial confirms the results from observational studies with better control of residual confounding due to the randomized and standardized design.
Click Here to Manage Email Alerts