Beginning in early childhood, researchers have found that otherwise healthy Black individuals show signs of slightly diminished heart muscle strength and a slightly higher blood pressure than their white counterparts, factors that may put them at an increased risk for early development of congestive heart failure.

Heart disease is the leading cause of death for all Americans, although death rates are higher in Black people than white people and other ethnic groups, and disease develops at a younger age, according to the press release. Despite this, congestive heart failure is the only adult cardiovascular disease that actually continues to increase in incidence, primarily because individuals are living longer.

Investigators at the Medical College of Georgia at Augusta University analyzed 673 individuals—about half male and female, and half Black and white. The participants have been followed at the Georgia Prevention Institute for more than 30 years as part of the August Heart Study, which seeks to understand the development of cardiovascular risk factors in children with a family history of risk factors, such as hypertension and heart attack.

The investigators said this appears to be the first prospective study to examine changes in cardiac muscle function in a group of healthy individual across their lifespan.

The researchers found that although ejection fraction held steady in Black participants over the 30-year course of the study, midwall fractional shortening (MFS) was able to document a fraction of a percentage point of change in heart function. Specifically, they found a .54% decrease in MFS in Black participants compared to white participants, as both grew from childhood into young adulthood. They also noted that as the size of the left ventricle grew by 1 gram, MFS decreased in Black participants by 0.01%.

Furthermore, the researchers found that as pressure inside the aorta slowly crept up over the years, MFS crept downward, indicating a decrease in muscle strength. Subtle decreases in MFS are associated with an increased risk of congestive heart failure. Although the authors said the small decreases they observed are not yet clinically significant in these young people, if the trend continues, they will likely become a factor in their heart health.

The investigators said lowering blood pressure in young Black individuals might help preserve heart function. A better diet, including foods low in salt and high potassium, along with regular physical activity likely will help, although medical treatment may still be necessary, according to the study.

Physicians and other health care providers should keep a close check on blood pressure starting in early adolescence, especially for populations at high cardiovascular risk, such as Black populations. Children with chronically higher normal blood pressures may also need an early assessment of their heart function or medication to lower their blood pressure in order to protect future heart health.

REFERENCE
Higher blood pressure over life span increases congestive heart failure risk in Black people [news release]. EurekAlert; February 8, 2021. https://www.eurekalert.org/pub_releases/2021-02/mcog-hbp020521.php. Accessed February 16, 2021.