An extensive UK study of more than 200,000 people has discovered that people’s risk of dementia with multiple heart conditions is three times as high.
The research was led by Oxford University and the University of Exeter and is one of the largest ever to explore the association between several heart conditions and dementia and one of the first to analyse the impacts of multiple health conditions. The results demonstrated that multiple heart conditions increase an individual’s dementia risk more than having a high genetic risk for the condition.
The study, which is published in The Lancet Healthy Longevity, employed data from people in the UK Biobank study who were aged 60 or older and had European ancestry. The researchers identified individuals who had been diagnosed with cardiometabolic conditions, such as diabetes, stroke, a heart attack, or any combination of the three, in addition to people who eventually developed dementia.
The investigation revealed a link between having more of these conditions and a higher risk of developing dementia. Moreover, people with all three heart conditions were three times more likely to develop dementia than those with the highest genetic risk.
Dr Xin You Tai, the Lead Author and Doctoral Student at the University of Oxford, said: “Dementia is a major global issue, with predictions that 135 million worldwide will have the devastating condition by 2050. We found that having such heart-related conditions is linked to dementia risk to a greater extent than genetic risk. So whatever genetic risk you were born with, you can potentially make a big impact on reducing the risk of dementia by looking after heart and metabolic health throughout life.”
Examining multiple heart conditions
The international research team, which also included experts from the universities of Glasgow and Michigan, identified that around 20,000 of the participants in the UK Biobank had been diagnosed with at least one of the three heart conditions, with over 2,000 having two conditions and 122 having all three.
Professor David Llewellyn, Senior Author, Professor of Clinical Epidemiology and Clinical Health at the University of Exeter, commented: “Many studies look at the risk of a single condition in relation to dementia, but health is more complex than that. We know that many patients actually have a range of conditions. Our study tells us that for people diagnosed with diabetes, stroke or a heart attack, it is particularly important to look after their health and ensure they are on the right treatment to prevent further problems and reduce their dementia risk.”
Exacerbating the risk of dementia
For their investigation, the researchers divided the 20,000 participants with heart conditions into three groups depending on their genetic risk, from highest to lowest. They based this on a comprehensive risk score that reflected multiple genetic risk traits relevant to people of European ancestry.
In addition, the team utilised brain imaging data from more than 12,000 participants, discovering widespread damage across the brain for individuals with more than one cardiometabolic condition, whereas having a high genetic risk was only linked to deterioration in specific regions of the brain.
Dr Kenneth M. Langa, Study Co-author, Professor of Medicine at the University of Michigan and Veteran Affairs, Ann Arbor Healthcare System, said: “Our research indicates that protecting the heart throughout life likely also has significant benefits for the brain. To look after your heart, you can engage in regular exercise, eat a healthy diet and do everything possible to ensure blood pressure, blood sugar, and cholesterol levels fall within guidelines.”
Dr Sara Imarisio, Head of Research at Alzheimer’s Research UK, concluded: “The evidence is clear that what’s good for your heart is also good for your head. A person’s risk of developing dementia is a complex mix of their age, their genes, and aspects of their lifestyle. In this study, researchers looked at data from a population of 60 years and older, including whether they had particular heart conditions, information about their genetics, and how these affected their risk of developing dementia. They found that people with multiple heart health conditions were even more likely to develop dementia than people who had an increased risk of Alzheimer’s disease due to their genetics
“These findings reiterate the importance of treating the causes of poor heart health, not just for its own sake, but also for the added benefit in terms of reducing the number of dementia cases. From the generosity of our supporters who enabled us to fund this work to the selflessness of the volunteers that made it possible, we want to say thank you, without you, research like this cannot take place. If anyone is worried about the health of your heart or your brain, please speak to your doctor.”