Bariatric surgery improves BP variability, may decrease resistant hypertension burden
Roux-en-Y gastric bypass surgery significantly reduced use of antihypertensive medications while promoting a similar 24-hour BP profile and nondipping status compared with medical therapy alone, according to findings published in Hypertension.
Carlos A. Schiavon, MD, PhD, FACS, from the Heart Hospital – HCor in São Paulo, and colleagues assessed the effect of bariatric surgery on a 24-hour BP profile, BP variability and resistant hypertension prevalence.
“Consistent evidence from the literature suggests that bariatric surgery is an effective strategy for promoting significant weight loss, metabolic and inflammatory improvements, BP reduction, among other favorable effects,” Schiavon and colleagues wrote. “This myriad of benefits translate into significant reduction in cardiovascular events and mortality, as suggested by observational studies.”
Impact of bariatric surgery
The researchers analyzed data from the randomized GATEWAY study of participants allocated into groups with bariatric surgery and medical therapy or medical therapy by itself for 12 months, with a primary outcome of 24-hour BP profile and variability (average real variability of daytime and nighttime BP). They also evaluated nondipping status and the prevalence of resistant hypertension as a secondary endpoint.
Schiavon and colleagues included 100 patients (76% women; BMI, 36.9 kg/m2).
After 12 months, 24-hour BP profile with nondipping status was similar in both groups, but the bariatric surgery with medical therapy group were taking fewer classes of antihypertensive medications compared with the medical therapy alone group (0 [interquartile range, 0-1] vs. 3 [interquartile range, 2.5-4]; P < .01).
Systolic nighttime BP was lower after bariatric surgery compared with medical therapy alone (between-group difference, –1.63; 95% CI, –2.91 to –0.36). Resistant hypertension prevalence was similar at baseline (surgery, 10%; medical therapy, 16%; P = .38), but was lower in the bariatric surgery group at 12 months (0% vs. 14.9%; P < .001).
Bariatric surgery is widely accepted for weight loss in grade 3 obesity and to improve glucose control in people with diabetes, but the procedure is not routinely indicated for treating hypertension, especially with grade 1 and 2 obesity, Schiavon and colleagues wrote.
“This observation is potentially explained by the lack of definitive data on prognosis. Future data from this study (prespecified to have a total follow-up of 5 years) and other investigations may help to define the role of bariatric surgery in hypertension treatment,” they wrote.
Many remaining questions
In a related editorial, John E. Hall, PhD, and Michael E. Hall, MD, both from the department of physiology and biophysics, department of medicine and Mississippi Center for Obesity at the University of Mississippi Medical Center, wrote: “There are many remaining questions. Does the duration of obesity influence the BP response to bariatric surgery? Are the BP lowering effects of bariatric surgery blunted by longstanding obesity and hypertension which may cause injury to target organ, especially the kidneys? Can bariatric surgery in obese individuals prevent the development of resistant hypertension and target organ injury if conducted early enough (eg, in adolescence)? With the rapid increase in bariatric surgeries worldwide, we should have the answers to these questions in the next several years.” – by Earl Holland Jr.
Disclosures: Schiavon reports he received funding from Johnson & Johnson Brazil. The editorial authors report no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.