Multiple Heart Conditions Linked to Dementia
If our primary care doctors in Delray Beach told you that having more than one risk factor for heart disease was as detrimental to your mental health as genetics, would you believe it? This is what a new large-scale study on dementia risks found.
According to the study, led by Oxford University and the University of Exeter and published last month in the journal The Lancet Healthy Longevity, having multiple heart-related conditions are linked to a greater risk of dementia than having a high genetic risk. It also confirmed the findings from a 2017 study that showed similar results.
The study
The researchers from this study reviewed the records of more than 200,000 people of European ancestry in the UK Biobank who were ages 60 or above. Of those, they found nearly 20,000 had been diagnosed with one of three heart-related conditions: stroke, heart attack, or diabetes. Over 2,000 had two conditions, and 122 had all three.
Within this population, the researchers discovered that the more of these conditions (known as cardiometabolic conditions) a person had, the higher their risk of dementia. Those who had all three conditions were three times more likely to develop dementia than control subjects who had a high genetic risk but none of the cardiometabolic conditions.
In addition to researching participants’ genetic history, they used brain-imaging data for more than 12,000 subjects and found that those with more than one of the three cardiometabolic conditions exhibited widespread damage across the entire brain. Those with a high genetic risk typically showed deterioration only in specific parts of the brain.
Prior research
Another large, long-term study conducted by researchers at Johns Hopkins University looked at nearly 16,000 middle-aged people beginning in the years 1987-1989. Participants were between 44 and 66 years old at the start of the study, which lasted 25 years, and was funded by the National Institutes of Health’s (NIH) National Heart, Lung, and Blood Institute (NHLBI).
Researchers examined the participants five times over the course of the study with a variety of medical tests, including cognitive tests of memory and thinking. In addition to in-person visits, the researchers collected health data from telephone interviews, caregiver interviews, hospitalization records, and death certificates. Results were published in 2017 in the journal JAMA Neurology.
More than 1,500 of the participants were diagnosed with dementia over the 25-year study period. The analysis confirmed prior findings that those with vascular risk factors in midlife, such as diabetes or hypertension, had a greater chance of developing dementia as they aged. Cigarette smoking was also found to increase the risk of dementia, along with prehypertension, a condition in which blood pressure levels are higher than normal but lower than hypertension.
The reason
In these and other studies, the overall health of the cardiovascular system has been shown to affect the brain as well.
As the Centers for Disease Control and Prevention (CDC) explains, “Your heart pumps blood through vessels to every part of your body, including your brain. Damage to blood vessels can lead to serious health conditions such as heart disease, stroke, and dementia. Keeping your blood vessels healthy can help you have a strong heart and brain.”
“The evidence is clear that what’s good for your heart is also good for your head,” Dr. Sara Imarisio, Head of Research at Alzheimer’s Research UK, and one of the Oxford study’s authors said in a statement.
“A person’s risk of developing dementia is a complex mix of their age, their genes, and aspects of their lifestyle. These findings reiterate the importance of treating the causes of poor heart health, not just for its own sake, but also the added benefit in terms of reducing the number of dementia cases.”
What you can do
Even if you have one of these heart conditions, you can improve your brain health by taking proper steps to improve your overall cardiovascular health.
“Many studies look at the risk of a single condition in relation to dementia, but heath is more complex than that,” said David Llewellyn, senior author of the Oxford study and Professor of Clinical Epidemiology and Clinical Health, University of Exeter, in a statement accompanying the release of the study.
“We know that many patients actually have a range of conditions,” he said. “Our study tells us that for people who have a diagnosis of 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 as well as to reduce their dementia risk.”
Dr. Kenneth M. Langa, co-author and Professor of Medicine at the University of Michigan and Veteran Affairs Ann Arbor Healthcare System, added, “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.”
