Mid-life resting heart rate of 75 beats per minute, doubling the risk of premature death

A resting heart rate of 75 beats per minute in mid-life is linked to a doubling of the risk of premature death from all causes, at least among men, according to research published in the online journal Open heart.

And the results show that an increase in the rate in men in their fifties is associated with an increased risk of heart disease over the next 11 years.

Resting heart rate – the number of heartbeats per minute when the body is at rest – usually changes with age, with lower rates indicating better cardiovascular fitness and more efficient cardiac function. A resting heart rate of between 50 and 100 beats per minute (bpm) is considered within normal range.

The researchers wanted to know what impact a higher than normal resting heart rate could have on long-term health and the risk of premature death (before the age of 75), and whether changes in the frequency could be important.

They studied a group of men aged 50 and over randomly selected from the general population, all born in 1943 in Gothenburg, Sweden.

In 1993, 798 out of a total of 1450 completed questionnaires on lifestyle, family history of cardiovascular disease and stress levels. They also had a complete medical examination including their resting heart rate.

This was divided into four categories: 55 bpm or less; 56-65 bpm; 66-75 bpm; and more than 75 bpm.

Resting heart rate was measured again in 2003 and 2014 among those who were still alive and willing to participate at these times (654 and 536, respectively) to track any change in frequency between 1993 and 2003 and all treatment, death or death. by heart disease / stroke or anything else, until 2014.

During the 21-year surveillance period, 119 (just under 15%) of the 798 original men died before their 71st birthday; 237 (nearly 28%) developed cardiovascular disease; and 113 (just over 14%) developed coronary artery disease.

Men whose resting heart rate was above 55 bpm in 1993 were more likely to smoke, to be less physically active and to be more stressed than those whose rate was lower.

They were also more likely to have other risk factors for cardiovascular disease, such as higher blood pressure and weight.

However, a resting heart rate greater than 75 beats per minute in 1993 was, however, associated with approximately twice the risk of death, regardless of the cause, cardiovascular disease and coronary heart disease, compared with a rest of 55 or less.

And a resting heart rate that was stable between 1993 and 2003, when men were 50 to 60 years old, was associated with a 44% reduced risk of cardiovascular disease over the next 11 years compared to a frequency resting heart rate that had increased during this period. period.

In addition, each additional increase in the rate was associated with a 3% higher risk of death, a 1% risk of cardiovascular disease and a 2% risk of coronary heart disease.

This is an observational study that, as such, does not establish the cause. The research was limited to men and the age of the participants may have been an influential factor, the researchers say.

But the results have clinical implications, they suggest, since it may be important to monitor changes in resting heart rate over time to discover the risk of future cardiovascular disease.