HCM tied to heart failure in women, all-cause death in men

Hypertrophic cardiomyopathy (HCM) is more common among men in Singapore, reports a study. Women with HCM are more likely to develop heart failure, while men tend to have a worse prognosis in terms of all-cause mortality.

“Our study found that in an Asian cohort, there were more male patients with HCM, while women were older at diagnosis and more commonly displayed an obstructive physiology,” the researchers said.

Some 295 patients diagnosed with HCM were recruited from a tertiary cardiology centre from 2010 to 2017. The researchers then assessed the impact of sex on the outcomes of HCM among Asians.

Of the HCM patients, 72 percent were men. On the other hand, women with HCM were older and had more comorbidities, such as hypertension and atrial fibrillation. [Ann Acad Med 2023;52:348-355]

On transthoracic echocardiography, men and women showed similar indexed left ventricular end-systolic and end-diastolic volumes, but the latter had more-than-moderate mitral regurgitation and a smaller left ventricular outflow tract (LVOT). Women were also more likely to have obstructive physiology with significant LVOT obstruction (defined as >30 mm Hg at rest).

Use of implantable cardioverter defibrillators was similar across sexes. Multivariable analysis revealed a higher risk of progression to heart failure requiring admission among women (hazard ratio [HR], 2.10, 95 percent confidence interval [CI], 1.05‒4.71; p=0.021) and a greater all-cause mortality among men (HR, 0.36, 95 percent CI, 0.19‒0.70; p=0.003).

The findings on male predominance among HCM patients while women tended to be older at diagnosis support those of other studies across the globe. [J Am Heart Assoc 2019;8:e014448; Eur Heart J 2017;38:3434-40; J Am Coll Cardiol 2005;46:480-487]

“However, it is unclear whether there is a significant genotypic or hormonal contribution to such findings,” the researchers said.

“Some postulated there may be a genetic modifier that affects the degree and progression of cardiac hypertrophy, which could have contributed to the later onset of clinically manifest disease and, thus, later presentation in women,” they added.

Another notable finding in the current study is the development of heart failure at older age among women. One potential explanation, according to the researchers, is the postmenopausal endocrine changes in women.

Based on earlier studies, oestrogen deficiency correlates with impaired ventricular relaxation, myocardial hypertrophy, and fibrosis. Such deficiency after menopause could contribute to the progression of heart failure. [Methodist Debakey Cardiovasc J 2017;13:4-8; Pharmacol Ther 2012;135:54-70]

“While women have a higher risk of progressing to heart failure, it was actually men who had a higher risk of all-cause mortality,” the researchers said.

“Unfortunately, as this was a retrospective study, the specific cause of death was often unavailable, and we were unable to adjudicate whether this higher rate of mortality was due to cardiovascular causes or related to HCM. This could be studied in future prospective studies,” they added.