Researchers at Mass General Brigham have developed a new way to measure the complexity of heartbeats using data from wearable pulse oximeters.
Their study, published in the Journal of the American Heart Association, shows that people with more complex heart rhythms tend to experience slower cognitive decline as they age.
The study involved 503 older adults, mostly women, with an average age of 82. Using a fingertip device to monitor pulse rates overnight, researchers found that greater heartbeat complexity was linked to better memory and thinking skills over several years. Traditional heart rate measures did not predict these changes as well.
Healthy hearts naturally vary their rhythm to respond to internal needs and external stress, reflecting a flexible nervous system. Reduced complexity may signal less adaptability and could be an early warning sign of brain health problems.
This noninvasive method could help identify people at risk for dementia earlier, allowing for timely interventions. The research team plans to explore whether this measure can predict dementia development.
This study highlights the important connection between heart health and brain function, suggesting that monitoring heart rhythm complexity might become a useful tool in protecting cognitive health as people age.