Extreme resting heart rates linked to higher stroke risk, study finds

A large-scale study has revealed that both very high and very low resting heart rates can raise the risk of stroke. The findings challenge the common belief that a lower heart rate always indicates better heart health. Researchers analysed data from over 460,000 participants to uncover the link between heart rate and stroke risk. The study showed that stroke risk was lowest in people with resting heart rates between 60 and 69 beats per minute (bpm). However, those with rates below 50 bpm faced a 25% higher chance of stroke. Extremely low heart rates, known as bradycardia, may reduce blood flow to the brain, increasing the likelihood of an ischemic stroke.

At the other end of the scale, participants with resting heart rates at or above 90 bpm were 45% more likely to suffer a stroke. Very high rates were connected to both ischemic and hemorrhagic strokes. The link between heart rate and stroke risk remained even after accounting for factors like high blood pressure, diabetes, and atrial fibrillation. High resting heart rates have also been tied to a greater risk of heart attack and early death. The study highlights that resting heart rate—a simple and widely available measure—could play a bigger role in assessing cardiovascular risk.

The research suggests that both extremely high and low resting heart rates should be monitored more closely. While a rate of 60 to 69 bpm appears safest, deviations at either extreme may signal higher stroke risk. Doctors could use this information to better evaluate patients’ cardiovascular health.