Patients who underwent metabolic and bariatric surgery had fewer than half the number of hospitalizations for both acute and chronic episodes of heart failure with preserved ejection fraction (HFpEF) in a retrospective analysis of more than 2 million Americans collected in a national database.
In a multivariate analysis that adjusted for several variables patients without a history of bariatric surgery had three- to fivefold more hospitalizations for acute events involving HFpEF, and more than double the rate of hospitalizations for chronic HFpEF events, David R. Funes, MD, said at the annual meeting of the American Society for Metabolic and Bariatric Surgery.
While this analysis has the limitations of being retrospective, observational, and entirely reliant on procedure codes to define medical histories and outcomes, it had the advantage of using a large database designed to represent the U.S. adult population, said Funes, a bariatric surgeon at the Cleveland Clinic in Weston, Fla.
HFpEF Effects Could “Extend” Surgery’s Use
The report “adds an important article to the literature where there is a true void in trying to discern the effect of bariatric surgery on HFpEF,” commented Tammy L. Kindel, MD, PhD, director of the bariatric surgery program at the Medical College of Wisconsin, Milwaukee, and designated discussant for the report. “Minimal studies [up to now] demonstrate that weight loss in any form can modify diastolic dysfunction in patients with HFpEF. Studies that investigate the impact of bariatric surgery on clinical outcomes in patients with HFpEF are probably the most important for extending use of metabolic surgery,” Kindel said.
She added that “one of the most difficult parts of studying HFpEF” is making a firm diagnosis that often involves excluding other potential causes. She also questioned Funes about his confidence that his analysis correctly identified patients only with HFpEF. Funes replied that the diagnostic codes his team used allowed for a clear distinction between patients identified with HFpEF and those with heart failure with reduced ejection fraction, but he also admitted that his study’s complete reliance on these codes introduced a limitation to the analysis.
Including Patients With Diastolic Dysfunction as Well as HFpEF
The study used data collected during 2010-2015 by the National Inpatient Sample, run by the U.S. Department of Health & Human Services in a case-control analysis that included 296,041 patients who had undergone some form of bariatric surgery and 2,004,804 people with no history of bariatric surgery selected as controls on the basis of their obesity.
The absolute numbers showed that, during the observation period, the incidence of acute HFpEF hospitalizations was 0.19% among those with prior bariatric surgery and 0.86% among those with no surgery, and the incidence of chronic heart failure hospitalizations was 0.01% among people with prior bariatric surgery and 0.05% among those without prior surgery. Funes said. He noted that, during the period studied patients, with HFpEF were usually identified as having diastolic heart failure, an older name for the same disease.
In multivariate analyses that adjusted for age, sex, race, hypertension, diabetes, smoking, and coronary artery disease, people without prior bariatric surgery and with hypertension had a 2.8-fold increased rate of acute hospitalizations for HFpEF, while those without hypertension or prior bariatric surgery had a 5.2-fold increased rate. In addition, control patients, regardless of hypertension status, had a 2.9-fold increased rate of hospitalizations for chronic HFpEF events. All these differences were statistically significant.
Funes also reported results from additional analyses that focused on a roughly 68,000-patient subgroup of those included in the study who had a history of coronary artery disease, including about 62,000 with no prior bariatric surgery and nearly 6,000 people with prior bariatric surgery. In a multivariate analysis of this subgroup, people without prior bariatric surgery had a 2.65-fold increased rate of hospitalization for a HFpEF event (either acute or chronic), compared with those who had undergone bariatric surgery.
Funes and associates and Kindel had no relevant disclosures.
This article originally appeared on MDedge.com, part of the Medscape Professional Network.