Changes in heart rate predict risk of mortality in healthy middle-aged men

A change in resting heart rate in healthy middle-aged men is tied to mortality risk, with those who experience a long-term rise in resting heart rate having an increased risk of mortality and those with a long-term decrease in resting heart rate having a reduced risk of mortality.

"Measuring heart rate is not expensive and not invasive," said Xavier P. Jouven, MD, PhD, lead investigator of a study that followed 4,320 men aged 42 to 53. All men had their resting heart rate measured at baseline (between 1967 and 1972) and then yearly during the next 5 years. Resting heart rate was determined by measuring the radial pulse during a 1-minute recording.

The men were followed for 20 years, during which time 1,018 died. The men were divided into 9 groups according to their baseline heart rate (≤60 bpm, 61 to 75 bpm, and >75 bpm) and the change in heart rate from their first to fifth examination (decrease >7 bpm, change of -7 to +7 bpm, and increase >7 bpm).

After adjusting for standard cardiovascular risk factors, men whose resting heart rate increased by more than 7 bpm had a 47% increase in mortality, whereas those whose resting heart rate decreased by more than 7 bpm had an 18% decrease in mortality. The relationship held up when looking at changes as small as 5 bpm or as great as 10 bpm, said Dr. Jouven, of Hôpital Européen Georges Pompidou, INSERM, Paris, France.

The increased risk of mortality with an increase in heart rate occurred in men regardless of their baseline heart rate, he said.

Heart rate changes could occur as a result of changes in physical activity, medications, or anxiety or other conditions, or may be due to genetic factors. Because the study was initiated before the era of beta blockers, Dr. Jouven said this class of medications could be ruled out as a factor in the findings.