Elevated Heart Rate Linked to Dementia Risk, Study Says

According to Alzheimer's Association, warning signs of dementia can include confusion, difficulty with words, and poor judgment. But a new study in the journal Alzheimer's & Dementia suggests there may be a non-mental aspect that should be considered as well—resting heart rate (RHR).

About the Study

Researchers looked at more than 2,000 people aged 60 and older living in Sweden and tracked different health markers every three or six years from 2001-2004 and 2013-2016. These markers included their RHR, which is defined as the number of times your heart beats per minute (bpm) while at complete rest.

A normal rate is 60 to 80 bpm. Adults with a high level of fitness can have a rate below 60, and the higher end is associated with increased health risks, including metabolic syndrome. For those over age 65, an RHR over 80 is considered poor.

In the recent study, participants who came in around that number on average had a 55% higher risk of dementia than those with an RHR of 60 to 69 bpm. Because of that, researchers suggest RHR should be considered during dementia screenings or possibly even earlier.

"We believe that early intervention, by identifying those with higher dementia risk, could have a substantial impact on quality of life since dementia onset may be able to be delayed," says lead author Yume Imahori, PhD, in the Department of Neurobiology at the Karolinska Institute in Sweden.

Possible Reasons

Although the study did not establish a causal relationship, Dr. Imahori says a possible explanation could be the association between cardiovascular issues and dementia. One major, established risk factor is high blood pressure, according to the National Institutes of Health. That is because problems in the vascular system can affect the blood supply to the brain, which may contribute to dementia development.

A high RHR may indicate cardiovascular issues even if those have not yet been diagnosed, Dr. Imahori adds. That means people with a higher RHR may not only be at higher risk of dementia, but also heart disease.

Another variable is likely inactivity. A lower RHR is considered an indication of fitness, so those with higher numbers tend to be more sedentary.

A meta-analysis that involved more than 250,000 participants found that people with sedentary behavior have a 30% higher risk of experiencing dementia. In that research, possible factors include inflammation, impaired glucose regulation, and high cholesterol—which also tend to raise the risk of cardiovascular disease.  

Understanding these associations is increasingly important, says Dr. Imahori, since the global burden of dementia is increasing rapidly. The number of people living with the condition is expected to reach 115 million by 2050. A simple detection tool like RHR could be an early warning sign that helps people make meaningful lifestyle habits, she adds.

Adjusting Your Heart Rate

The best way to lower RHR is through consistent exercise, says Rocky Snyder, CSCS, conditioning and strength coach and author of "Return to Center: Strength Training to Realign the Body, Recover from Pain, and Achieve Optimal Performance."

Not only can that improve heart rate and your overall cardiovascular system, he says, but it can also address an age-related decline in muscle mass, balance, flexibility, power, and speed.

“Unfortunately, when the body reduces its activity level, the aging process accelerates,” he notes. “Staying active on a regular basis is the key to maintaining and recovering strength. Typically, in our culture, as people age, they are encouraged to slow down. But we shouldn't become less active, quite the contrary."

Older people just starting an exercise program should first check with a healthcare provider, particularly if they have cardiovascular issues, and then begin gradually, Snyder advises. Strength is important, but he says a program should also include mobility, flexibility, coordination, speed, and endurance.

Seeking guidance from a certified fitness professional who specializes in older populations can also be useful, he adds. Over time, it is likely that your RHR will improve with conditioning, but be sure to talk to a healthcare provider if exercise does not seem to have an effect. There may be other underlying factors keeping it elevated.