Mike Glenn thought something was wrong with his Fitbit.
The 34-year-old was camping in Wyoming in May when he started having trouble breathing. He felt fine overall, but his left shoulder began to ache and he broke out in a sweat. "It's probably just a chest cold," Glenn thought.
But his Fitbit Ionic seemed to be going crazy. His heart rate was 40 -- about half its normal rate.
"That can't be right," Glenn thought. He took off the smartwatch, cleaned it and put it back on his wrist. It still flashed 40. Glenn's wife, a nurse, pressed her head against his chest and listened. She told him they needed to get to a hospital. Immediately.
Glenn was having a heart attack. His right coronary artery was completely blocked, and his central artery was 80 percent blocked. He would later learn that as a diabetic, nerve damage associated with the condition had dulled his senses, which is why he hadn't felt a common symptom of heart attacks: chest pain.
"If I didn't have my Fitbit on, I don't know if I would've put it together that all these symptoms were adding up to a heart attack," Glenn said. "That was the sign to me that I had a problem."
The technology in smartwatches has come a long way since the early days of wearables, when rudimentary step and calorie counters were about as advanced as the devices got. Now, a new generation of devices is ushering in heart-, sleep- and blood-monitoring functions that push the accuracy of laboratory equipment to your wrist.
In September, Apple introduced an FDA-cleared EKG feature in its Series 4 Watch. The feature, which hasn't gone live yet, warns wearers about abnormal heart rhythms linked to atrial fibrillation. Fitbit and Garmin are developing features that can help detect atrial fibrillation, sleep apnea and other conditions. In April, Garmin integrated the Cardiogram app into its devices. Cardiogram's DeepHeart algorithm has demonstrated high accuracy in detecting atrial fibrillation, hypertension, sleep apnea and diabetes.
The new generation of functions could kick-start the smartwatch category, which has failed to live up to the technology industry's high hopes. High-end devices are taking over from basic fitness trackers, which analysts say is an indication that users want devices that can do more than just count our steps. Better health capabilities could give users, particularly those with medical problems, a reason to strap the devices to their wrist.
"If [a wearable is] helping you manage a medical condition, it probably will turn out to be a durable utility," says Eric Topol, executive vice president at Scripps Research, a nonprofit scientific institute. The time-stamped data wearables gather can be helpful when formulating a treatment, he says, because it's collected in the real world rather than in a contrived, laboratory environment.
Sixteen percent of US households with broadband connections report owning at least one smartwatch, according to data from Parks Associates, a market research firm. That's up from 4 percent in the first quarter of 2014. Another 13 percent of households say they intend to buy a smartwatch in the next year.
Kristen Hanich, an analyst at Parks, says smart technology that can more accurately collect and interpret the data smartwatches generate will boost adoption.
"Let's take what we already have and use it in a better way so that we get better data, better insights and we can actually have some sort of a meaningful impact," Hanich says.
The FDA hurdle
Companies still have to get through the FDA if they want to market their product as a medical device, so manufacturers are conducting in-depth studies to ensure the accuracy of their products. The FDA also launched a precertification pilot program last year, designed for companies that want to speed up the clearance process for future medical devices. Some of the companies selected for that program include Apple, Samsung and Fitbit.
FDA clearance serves as validation for consumers, says Gartner analyst Tuong Nguyen, giving them confidence in a product that might be otherwise viewed as a luxury item rather than a medical device.
Tim Bajarin, an analyst at Creative Strategies who follows the wearables industry, says he's relied on the accuracy of his devices since having a triple bypass. Now, he uses an Apple Watch Series 4 to monitor his heart rate. He also linked his Dexcom Continuous Glucose Monitor to his Apple Watch so that he can see his blood sugar levels on the wearable, as well as his AliveCor's KardiaBand, a real-time EKG band.
Bajarin, like other industry and medical analysts, supports the expanded use of wearable devices, but cautions a wrist monitor shouldn't be seen as a replacement for medical care.
"Smartwatch wearers who use health monitoring apps need to see them as a means to track their health and, if needed, warn them of potential health issues," Bajarin says. "They're not a replacement for a true medical evaluation or diagnosis."
What's next for medical wearables
More tech companies, including Samsung and Google, will likely develop wearable devices with increased health and medical features, analysts say. Samsung has already said it's developed an emergency response feature for smartwatches and a method for connecting first responders to their teams using Samsung Galaxy smartwatches.
Companies like Bose and Samsung offer augmented hearing devices, known as hearables, that help people listen to conversations in noisy environments. Verily, a Google sister company, is working on contact lenses for age-related farsightedness, as well as an intraocular lens designed to improve eyesight after cataract surgery. Verily had previously worked on a glucose-sensing contact lens for people with diabetes, but shelved the project in November.
In the next five years, analysts say, we'll see features such as blood pressure and glucose monitoring rolled out on wearables. Increased battery life will mean we won't have to take off wearables at night, so we'll be able to monitor conditions such as sleep apnea.
"We're going to see an absolute revolution on our wrists," says Paul Testa, chief medical information officer at NYU Langone Health. When patients come into the emergency room with symptoms of a stroke, says Testa, who is also an emergency medicine physician, doctors try to figure out the last time a patient was at his or her baseline, a measure known as a "well" moment. "Won't it be incredible in five years when an Apple Watch or a phone knows their last 'well' time?" he asks.
Glenn, the hiker in Wyoming, was quickly taken to a hospital and then flown to a facility in Salt Lake City, where he lives, for surgery. He went through three months of cardiac rehab.
Glenn says the up-to-the-minute data on his Fitbit prompted him to take action while in the woods. Without that information, he might not have realized he needed help.
"My Fitbit is what really brought the problem I was having to my attention," Glenn says. "It's my safety blanket."
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The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.