Smart watches

Smartwatches track the health of darker-skinned people less effectively

“There are some limitations for people with darker skin tones when using these devices.”

WASHINGTON- Does skin color determine how well wearables work when it comes to tracking a user’s heart health? A new study suggests this is the case, as smartwatches seem to provide less accurate data for people with darker skin tones.

Joggers and other fitness enthusiasts are increasingly turning to these trendy devices to monitor their heart rate and body rhythms during exercise. More and more people are using them to track their general health and the quality of their sleep.

However, a resident physician at the University of Alberta found that measurements can be less accurate depending on skin tones. The results come from a systematic review of 10 previously published studies involving more than 460 participants. The research is the first to pool numbers from multiple studies to look specifically at how skin tone can affect the accuracy of heart data in wearable devices.

“People should be aware that there are some limitations for people with darker skin tones when using these devices, and the results should be taken with a grain of salt,” says the co-lead of the study, Dr. Daniel Koerber in a press release.

“Algorithms are often developed in homogeneous white populations, which can lead to results that are not as generalizable as we would like. Ongoing research and development of these devices should emphasize the inclusion of populations of all skin tones so that the algorithms developed can better adapt to variations in innate skin light absorption.

Light beams have issues with some skin tones

The research team identified 10 studies, from 622 scientific papers, that reported heart rate and rhythm data for consumer wearable technology based on a participant’s race or skin tone. Of these studies, four found that heart rate measurements were “significantly less accurate” in darker-skinned people compared to lighter-skinned people or measurements from validated devices, such as heart rate monitors. chest strap or electrocardiograms.

One study reported that although there was no difference in heart rate accuracy, wearables recorded “significantly fewer” data points for people with darker skin tones. Dr. Koerber explains that most wearable devices detect heart rate and rhythm by directing a beam of light at the wrist and then detecting the amount of light absorbed. Greater absorption of light indicates a greater volume of blood flowing through the veins under the skin.

The study results suggest that the signaling process might not work as well with darker skin that contains more melanin, which absorbs light. In addition to the growing use of wearables to monitor physical activity and sleep patterns, interest in using consumer wearables for medical research and even early detection of heart problems has increased in recent years. years.

“There are a lot of claims that these devices can detect heart rhythm problems like tachycardia, bradycardia, and even atrial fibrillation,” says Dr. Koerber. “We want to be able to inform healthcare providers about the reliability of these data collection sources in all patients, regardless of skin tone.”

Could the green light be the solution?

The researchers say the study underscores the importance of ensuring that technology meets the needs of diverse populations, especially when their job is to improve health. The team notes that recent studies have shown that other devices — such as pulse oximeters that measure the amount of oxygen in the blood — don’t work as well for people with darker skin. This can have serious health consequences if the problems go undetected.

“It is important to explore alternative options to ensure that we can create a more equitable solution in healthcare and not just in the consumer industry,” Dr. Koerber concludes.

The researchers add that there is evidence that certain wavelengths of light, particularly green light, are more accurate on all skin tones.

The researchers present their findings at the American College of Cardiology’s 71st Annual Scientific Session.

Stephen Beech, editor of the South West News Service, contributed to this report.