New research provides compelling evidence that long-term exposure to high blood pressure increases the risk of heart valve disease, with significant implications for clinical practice guidelines and health management.
"Clinical practice guidelines currently make little reference to preventative strategies for major valvular heart diseases, but this study highlights that high blood pressure should be considered a major risk factor, much as it is for heart attacks, stroke and other cardiovascular conditions," said Lead Researcher Milad Nazarzadeh, of The George Institute for Global Health, UK and Oxford Martin School's Deep Medicine programme at the University of Oxford.
"A few earlier studies suggested that experiencing high blood pressure is associated with an increased risk of valvular heart disease, but whether the observed associations were causal was uncertain. This study, which expands on our previous work, provides the best evidence so far for this causal association, and confirms that exposure to high blood pressure substantially increases the chances of major valvular disease (including aortic stenosis, aortic regurgitation and mitral regurgitation)."
The research team used a state-of-the-art, gene-based method called Mendelian randomization to determine the causality of this association. From birth, we all have genes that are known to be associated with a propensity for either normal or high blood pressure in later life. Researchers grouped participants based on their genetic blood pressure characteristics, and were then able to directly compare outcomes in terms of the risk of major valvular diseases associated with high blood pressure.
The findings, published in JAMA Cardiology today, are from a study of half a million UK men and women aged between 40 to 96 years from the UK Biobank study.
They reveal that:
- Each 20 mmHg increase in systolic blood pressure roughly equates to a threefold increase in the odds of developing aortic stenosis, a condition in which the valve that controls how blood is pumped from the heart to the main artery doesn't open fully.
- A similar pattern of association was observed for two other major heart valve conditions (aortic regurgitation and mitral regurgitation).
Patients with heart valve disease may suffer symptoms such as irregular heartbeat, shortness of breath, fatigue, fainting and dizziness. The new research provides further evidence of the importance of controlling high blood pressure, and doing so at the earliest opportunity, to limit the time that individuals are exposed to the condition.
The study was funded by the National Institute for Health Research through the Oxford Biomedical Research Centre, the Oxford Martin School at the University of Oxford, the UKRI's Global Challenges Research Fund, and by the British Heart Foundation.
