This article is more than 5 years old. Information may no longer be current.
Abdominal obesity confers mortality risk in HFpEF
Click Here to Manage Email Alerts
Among patients with HF with preserved ejection fraction, risk for all-cause mortality was higher in those with abdominal obesity compared with those without it, according to new findings.
Tetsuro Tsujimoto, MD, PhD, and Hiroshi Kajio, MD, PhD, both from the department of diabetes, endocrinology and metabolism at Center Hospital, National Center for Global Health and Medicine, Tokyo, analyzed the association between abdominal obesity and all-cause mortality risk in patients with HFpEF from the TOPCAT trial.
Of the 3,310 patients analyzed, 2,413 had abdominal obesity, defined as waist circumference of at least 102 cm in men and at least 88 cm in women.
During a mean follow-up of 3.4 years, 500 patients died. The all-cause mortality rate in those with abdominal obesity was 46.1 per 1,000 person-years vs. 40.7 per 1,000 person-years in those without abdominal obesity, the researchers wrote.
After multivariable adjustment, all-cause mortality risk was higher in those with abdominal obesity (adjusted HR = 1.52; 95% CI, 1.16-1.99), as was CV mortality risk (aHR = 1.5; 95% CI, 1.08-2.08) and non-CV mortality risk (aHR = 1.58; 95% CI, 1-2.51), Tsujimoto and Kajio wrote.
The results were consistent regardless of age, sex, obesity, diabetes, ischemic heart disease, atrial fibrillation, assignment to spironolactone in TOPCAT or NYHA functional class (P for interaction .17 for all), according to the researchers.
“Further studies are required to elucidate the detailed mechanisms underlying the association between abdominal obesity and adverse outcomes in patients with HFpEF,” they wrote.
In a related editorial, Carl J. Lavie, MD, FACC, FACP, FCCP, professor of medicine and medical director of cardiac rehabilitation and preventive cardiology and staff cardiologist at the John Ochsner Heart & Vascular Institute at the University of Queensland School of Medicine, and colleagues wrote that studies of patients with HF with reduced ejection fraction have demonstrated an obesity paradox, in which abdominal obesity confers a lower risk for mortality, but the present study shows the same is not true in patients with HFpEF after adjustment, but the obesity paradox was present before adjustment.
“It is possible that the pathophysiologic contribution from obesity is greater in HFpEF than in HFrEF,” they wrote. “Nevertheless, even in this current study, in univariate analysis, those with elevated [waist circumference] did not have higher mortality.”
They concluded that: “The constellation of findings support purposeful weight reduction and increasing levels of physical activity and exercise training to increase cardiorespiratory fitness to improve prognosis in HF, including patients with HFpEF. However, the clinical implications of this study are not clear, because the data are not able to establish causality and did not assess the question of whether specifically reducing [waist circumference] improves the prognosis in patients with HFpEF.” – by Erik Swain
Disclosures: Lavie reports he is the author of The Obesity Paradox. The authors and other editorial writers report no relevant financial disclosures.
Perspective
Back to Top
Ian J. Neeland, MD
It's been widely recognized for over 3 decades that abdominal obesity is a risk factor for morbidity and mortality in both primary and secondary prevention populations. The specific link between abdominal obesity and HFpEF outcomes is particularly relevant since obesity may be a stronger risk factor for HFpEF than HFrEF. Indeed, in the current study, 73% of all patients with HFpEF had abdominal obesity. These findings add to an existing literature that accumulation of excess fat in the abdomen has deleterious effects on both CV and non-CV outcomes.
The obesity paradox is described using BMI, not waist circumference. This study did not assess the obesity paradox using BMI in patients with HFpEF, so we don't actually know whether there was an obesity paradox in this study. Waist circumference is in fact a suboptimal marker of visceral obesity. Further studies that use direct imaging assessments of visceral fat may provide even further insight into the obesity-HFpEF relationship in the future.
Furthermore, given the extreme imbalance in abdominal obesity rates among those included in the study, there is likely a significant selection bias when defining the groups on abdominal obesity. We see this play out in the differences between the unadjusted mortality rates (which are not significantly different between groups) and the adjusted rates.
The findings of this study should be interpreted with caution since the survival curves were essentially identical until they started to separate very late in the study when only a small percentage of patients were still included. I think the message stays the same: abdominal obesity, reflective of excess visceral fat accumulation, is harmful and may be associated with increased mortality among patients with HFpEF.
Click Here to Manage Email Alerts