World Heart Day 2021 – Understanding heart health in older endurance athletes
Published: 29 September 2021
Today is World Heart Day, bringing with it an opportunity to raise awareness of cardiovascular diseases, which remain the world’s biggest killer.
Here at St George’s, University of London, we have undertaken ground-breaking studies in cardiovascular research, including practice-changing studies on sudden cardiac death, lymphatic disorders and sports cardiology.
This year, the university has launched the UK’s only Sports Cardiology Masters programme, taught by world-leading experts from the Centre for Inherited Cardiovascular Conditions and Sports Cardiology at St George’s NHS Foundation Trust.
Our researchers, working closely with athletes, have helped pave the way for better care for those that are often considered to be the healthiest in society, but can have underlying conditions missed in normal check-ups.
Earlier this year, a team from the Cardiology Clinical and Academic Group at St George’s published a paper reviewing the latest evidence on heart conditions affecting older endurance athletes.
The potential causes of increased risk in endurance athletes
“My thesis looks at the effects of endurance exercise on the heart in middle-aged men in Lycra, who are the group at greatest risk of sudden death in exercise,” says Dr Gemma Parry-Williams, first author on the evidence review, who is completing her PhD at St George’s in cardiology research. The review covers the evidence from more than 50 research papers on the topic.
“The review explores what we know so far about older endurance athletes and their coronary risk,” she continues.
“It’s a real deep dive into the different angles of that, what the knowns and unknowns are, and what areas we need to look at further.”
The paper highlights that studies in male athletes over 40 years old have shown that this group has higher levels of calcium in their arteries supplying blood to the heart compared to others. Something which can be a sign of harmful narrowing and stiffening of these arteries in non-athletic individuals.
However, due to the differing physiology of an athlete’s heart, the evidence isn’t clear as to whether higher levels of calcium are a critical factor in the greater risk of myocardial infarction (heart attack) and/or sudden death – it may be that there are other factors or mechanisms that play a role.
“The overriding conclusion was, at the moment, we don’t have the answer,” says Dr Parry-Williams. “We don’t know if the artery calcification in athletes, which would lead to an adverse prognosis in a normal individual, would translate to an adverse prognosis in the athlete.”
The review points to the differing physiology of the heart and environmental conditions that could influence the risk of myocardial infarction in this group, from increased blood pressure to scarring on the heart to dietary differences. The next steps are to explore these different variables and find the best predictors of dangerous heart conditions.
Identifying other factors that may play a role
“What we need is more prospective data and longitudinal studies,” says Dr Parry-Williams. Studies that follow large groups over long periods of time will help researchers to investigate the significance of different factors and identify the people who may be at greatest risk. With this in mind, preventative steps or treatments could then be specifically targeted at these groups to improve outcomes in future.
Another consideration, is that there is very little data looking at the same factors in women, adds Dr Parry-Williams.
“So far women don’t seem to have the same preponderance for high calcium levels as men,” she says.
“Women’s coronary risk is much lower than men at a younger age, but their risks meet post-menopause. We need to understand if this is something which is driven by testosterone, age or something else.”
Dr Parry-Williams explains that further studies looking at markers of coronary disease and other aspects of heart physiology will be necessary to understand the differences in risk between men and women.
Exercise remains key for a healthy lifestyle
With evidence linking prolonged high intensity exercise over many years to an increased risk of heart conditions, this could raise concerns about people’s motivations for physical activity. However, the advice remains clear that regular exercise provides marked health benefits, decreasing the risks of not just heart diseases, but also diabetes, certain cancers and other conditions.
“Our review confirms we don’t know that the exercise itself is what’s behind the potential increased risk in endurance athletes,” explains Dr Parry-Williams. “And with this in mind, that should hopefully encourage the average individual to exercise, as we know that light to moderate activity has clear benefits for both physical and mental health.”
The next steps for the research team will now be to attempt to identify the clear risk factors for heart conditions in athletes, giving clinicians the information they need to prevent and treat individuals at greatest risk.
If you’re interested in following in the footsteps of Dr Parry-Williams and other members of the Cardiology Clinical and Academic Group at St George’s, you can find out more about the Sports Cardiology programme at the university on our website.