Men whose hearts beat faster over time are likely to die earlier than those whose hearts maintain an unchanging cadence year after year, according to a 20-year study of French police officers. But a heart with a slowing rate is likely to keep beating for the longest time.
The newfound relationship suggests that doctors could use trends in the routine vital sign of heart rate to gauge which of their patients are in danger.
Doctors have long associated a racing heart with poor health and risk of death, says Xavier P. Jouven, a Paris-based electrophysiologist and epidemiologist at the Georges Pompidou European Hospital–INSERM. However, no past study has examined changes in heart rate over time, he says.
Jouven and his colleagues studied 4,320 Frenchmen who were serving on the Paris police force when the study began in 1967. Participants began the study at ages 42 to 53. For the first 5 years of the study, each volunteer had a physical exam and other tests annua