The Jackson Heart Study continues to yield insights about the nature of cardiovascular disease in minority populations.
The Jackson Heart Study, a large population-based study to examine the factors that contribute to cardiovascular disease in African Americans, continues to yield results, with the latest findings on elevated baseline heart rate appearing in JAMA Cardiology.
Researchers led by Kishan S. Parikh, MD, evaluated data from 5261 African American participants whose baseline heart rate was measured by a 12-lead electrocardiogram without pacing or atrial fibrillation, with follow-up beginning in September 2000 and continuing through December 2011. The study team examined the associations between heart rate at baseline and all-cause mortality and heart failure hospitalization, using Cox proportional hazards regression models.
Of the study population, 36.5% were men, with a median age of 55.7 years, and a baseline heart rate of 63 beats per minute (bpm). The 20% of participants with the highest heart rates (73-118 bpm) had higher rates of diabetes and hypertension, and higher body mass index, coming in at 32.4 on average.
This group also reported much less physical activity, with half the group reporting absolutely no physical activity during the week. The group also reported being less likely to use beta blockers but more likely to consumer caffeine. Each increase of 5 beats per minute was associated with a 14% increase in mortality and a 10% increase in hospitalization, and similar patterns were seen in the groups with lower heart rates.
African American patients who had higher resting heart rates at the start of the study were more likely to smoke and have diabetes, 2 risk factors seen in higher numbers in minority populations.
“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. “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.”
Parikh KS, Greiner MA, Suzuki T, et al. Resting heart rate and long-term outcomes among the African-American population: insights from the Jackson Heart Study [published online September 28, 2016]. JAMA Cardiol. 2016. doi:10.1001/jamacardio.2016.3234.