The Relationship Between Resting Heart Rate and Age in Adult Nigerians

Background: Resting heart rate is related to cardiovascular mortality as well as to all-cause mortality. It is therefore important to know whether resting heart rate changes with age in adults. The aim of this study was to determine the relationship between heart rate and age in adult Nigerians. Methods: It was a retrospective study on adult Nigerians attending a University Teaching Hospital in Nigeria. All the needed data were retrieved from the medical records. Heart rate was calculated from the electrocardiogram and correlated with age. Results: There were 99 cases aged between 20 and 54 years and comprised of 60 males and 39 females. The mean heart rate was 73.40±13.16 beats/minute. Across the various decades, the mean heart rate in beats per minute was 73.46±10.70 in the third decade, 75.52±12.16 in the fourth decade, 72.38±13.91 in the fifth decade, and 71.60±18.77 in the sixth decade of life (p=0.770). Heart rate correlated negatively and weakly with age (r=- 0.034, p=0.736). There were more cases of sinus bradycardia than sinus tachycardia, but the proportion of cases with heart rate outside 60 beats per minute to 100 beats per minute was small. Conclusion: This study showed that resting heart rate did not change with age in young adult and middle-aged Nigerians who had no clinical evidence of heart disease. A greater proportion of them were in normal sinus rhythm.