Higher Activity Levels Tied to Lower Mortality Rate With Atherosclerosis

By Lisa Rappaport

June 18, 2020

(Reuters Health) - Older adults with high atherosclerosis burden who report high levels of physical activity have lower mortality rates than counterparts who get little or no exercise, a recent study suggests.

Researchers examined data on 2,318 patients ranging in age from 65 to 84 years old who underwent coronary artery calcium (CAC) scanning from 1998 to 2016. At the time of their scans, patients completed questionnaires about chest pain and other cardiac symptoms, cardiac risk factors, medication use, and physical activity levels (rated on a scale from 0 to 10, representing "none" to "always").

After a mean follow-up of 10.6 years, 533 patients (23%) had died. The annualized mortality for the entire cohort was 2.3% per year, with the highest mortality (2.9% per year) among people with the lowest activity levels and the lowest mortality (1.7% per year) among those with the highest activity levels.

Physical activity levels didn't appear to alter survival in patients with low CAC scores (0-99). However, in patients with moderate CAC scores (100-399), the risk for all-cause mortality increased 2.07-fold among those with low physical activity compared to patients with high physical activity.

In patients with CAC scores over 400, all-cause mortality increased 2.35-fold for patients with low versus high activity.

"Exercise does not reduce the amount of calcium in the coronary arteries, but it improves patients' heart health and reduces future mortality through a number of established mechanisms," said Dr. Alan Rozanski, a professor of medicine at Icahn School of Medicine at Mount Sinai and chief academic officer for the Department of Cardiology at Mount Sinai Morningside Hospital in New York City.

When people are completely sedentary, they experience an increased risk for insulin resistance and diabetes, inflammation, hypertension, visceral fat accumulation, and loss of muscle strength and function," Dr. Rozanski, who led the study, noted in an email.

"Exercise does all the opposite, thus reducing the risk of both heart disease and other chronic illnesses," he said.

Among all clinical parameters, age and the magnitude of CAC score were the most potent predictors of mortality, followed by physical activity, the researchers report in Mayo Clinic Proceedings.

Patients who reported higher activity levels were less likely than those with the lowest activity to have hypertension (40.5% vs 51%), obesity (7.6% vs 25.6%), diabetes (5.6% vs 11.7%), or to be smokers (2.9% vs 7.7%).

One limitation of the study is that physical activity was self-reported, and not independently verified.

In addition, comorbidities unmeasured in the study might have impacted patients' outcomes, Dr. Jamal Rana, chief of cardiology in the East Bay for the Permanente Medical Group in Oakland, California, commented by email.

Even so, the findings support the consensus that regular exercise improves heart health and longevity, said Thijs Eijsvogels, an exercise physiologist at Radboud University Medical Center in Nijmegen, the Netherlands, who wasn't involved in the study.

"The underlying mechanisms of the association between exercise and coronary atherosclerosis is currently not fully understood, but it is expected that cardiovascular risk factors such as blood pressure, lipid levels and inflammatory status play a role," Eijsvogels said by email. "Exercise improves these factors, whereas there is also a link between these factors and the magnitude of calcium deposits in the coronary arteries as well as the risk of all-cause mortality."

SOURCE: https://bit.ly/3ebOOLF Mayo Clinic Proceedings, online June 5, 2020.