Higher resting heart rates in African Americans are associated with increased mortality, hospitalizations

An analysis of a prospective study found that higher baseline heart rates in African Americans were associated with increased mortality and heart failure hospitalizations.

Partcipants with the highest resting heart rates also had higher rates of diabetes and hypertension, higher body mass index, less physical activity and lower beta-blocker use.

Lead researcher Kishan S. Parikh, MD, of the Duke Clinical Research Institute in Durham, North Carolina, and colleagues published their results online in JAMA Cardiology on Sept. 28.

The researchers mentioned that African Americans have more hypertension, diabetes, coronary artery disease and heart failure compared with other racial groups.

For this analysis, they examined 5,261 African Americans who participated in the Jackson Heart Study, a community-based, observational study in Jackson, Mississippi. At baseline, the median heart rate was 63 beats per minute.

Participants were grouped into quintiles based on their baseline heart rate. The highest heart rate quintile included more women and had higher rates of heart failure, diabetes, hypertension and chronic lung disease.

During a follow-up period of 8.9 years, participants in the highest quintile group had an increased mortality risk. After adjustment, each five beats per minute increase in heart rate was associated with a 14 percent increase in the hazard of mortality. Elevated heart rate was also associated with a 10 percent higher risk of heart failure hospitalization through seven years of follow-up.

The researchers noted that participants with diabetes and current smokers had the highest risk for developing an elevated heart rate.

The study had a few limitations, according to the researchers, including its retrospective and observational design. They also mentioned that participants self-reported many of the covariates. In addition, they results did not reflect day-to-day variations in heart rates or heart rate response to physical exertion.

“African American patients presenting with higher resting heart rate are at increased risk for long-term adverse outcomes, including all-cause mortality and heart failure hospitalization,” the researchers wrote wrote. “Increased heart rate is associated with smoking and diabetes, and further study is needed to understand factors contributing to its development. ... These observations are similar to those seen in white populations, but further study is needed to assess the effect.”