Apple Watches' hypertension alerts just put every smartwatch rival on notice

Hypertension warnings on the Apple Watch Series 11 and Ultra 3 are the most universal "killer feature" I've seen on a smartwatch in years. It's not direct blood pressure monitoring, but that almost makes Apple's new system more compelling — and rival brands will be scrambling to emulate it.

Users in Europe or Asia can get smartwatch-based blood pressure tracking with a Huawei Watch D2 or Galaxy Watch 8 (with a cuff). But unless you're aware of chronic high blood pressure issues, you may not take advantage of this tool often. And a smartwatch won't replace a medical-grade blood pressure monitor.

I won't downplay the usefulness of convenient, on-the-go smartwatch BP checks for anyone unwilling to go to a doctor. But since Samsung has never gotten FDA approval — and several clinical studies with Galaxy Watches showed "insufficient accuracy" and "substantial pre-post calibration BP difference" — it's not something I'd actively recommend to at-risk relatives, even if I could.

Samsung also has a newer, indirect method of predicting hypertension — its Vascular Load stat — but it's not as straightforward as Apple's method, which will come to "more than 150 countries and regions," including the U.S. and EU this month, and pass FDA clearance "soon."

Once it does, I could see the Apple Watch Series 11 becoming even more popular than past models. Anyone in an at-risk age group, or whose family is predisposed to chronic high blood pressure, will want these early warning signs.

Apple found a depressingly common condition to predict

The CDC reports that 119.9 million American adults, or 48.1%, suffer from hypertension, while only 27 million have their condition "under control." 34 million Americans with hypertension had yet to fill or start taking their prescriptions. And "1 in 5 adults with high blood pressure is unaware of it and would not report having it."

Hypertension was a "primary or contributing cause of 664,470 deaths" in the United States in 2023, primarily from heart attack, heart failure, or stroke. Worldwide, the WHO estimates 1.28 billion people have hypertension, with only 42% "diagnosed and treated."

These numbers speak for themselves. Chronic high blood pressure is painfully common, and the people with it either aren't aware or aren't willing to treat themselves, whether due to financial concerns or because they're otherwise healthy and assume they don't need to worry.

For something like sleep apnea or AFib, a smartwatch alert is obviously useful, but at least these conditions have physical symptoms that you could detect on your own. With hypertension, Apple correctly notes in its press release, it "often has no symptoms" and "can be easily missed" if you only get readings once a year at the doctor's office.

Apple used "training data from multiple studies totaling over 100,000 participants," synced up against a "clinical study of over 2,000 participants," to make its machine learning algorithm. It'll then compare 30 days of optical HR data against its own data to spot any warning signs.

Apple predicts that out of the millions of users with an Apple Watch S9, S10, S11, Ultra 2, or Ultra 3, it'll spot signs of hypertension in a million people "within the first year."

That could very well prove hyperbolic, and I'll side-eye Apple if the FDA takes long to validate the feature. However, I'm truly optimistic that this could end up being a widespread tool, building awareness for a pervasive and dangerous condition. Regardless of which smartwatch brand you're a fan of, that's a great thing.

Android and fitness watches have their own life-saving tools

Anyone who wears a Galaxy Watch 8, Watch 8 Classic, or Watch Ultra 24/7 will get Samsung's Vascular Load data, which takes your sleep data and "measures blood volume and vascular stiffness and precisely analyzes changes in stress on blood vessels."

Arterial stiffness is one potential sign of hypertension, among other heart conditions. But Samsung's Vascular Load graph is more about pointing out how lifestyle choices like sodium intake or drinking cause heart strain in the short term, and while that's valid, it also puts the onus on the user to get better scores when the true cause might be genetic. Plus, it focuses on sleep strain, not necessarily strain during the day.

I think Samsung could end up launching something more targeted to hypertension in the future, based on the data it collects now, and it should. Hopefully, other Android watch brands will follow suit eventually.

As for other life-saving smartwatch tricks, the most obvious one is Google's Loss of Pulse detection, which contacts emergency services during cardiac arrest or other major heart issues. If no one is around to report it, this could save your life, though it's obviously a last resort for someone with unresolved health issues.

On the preventative front, Samsung, Google/Fitbit, Withings, and Apple offer passive irregular heart rhythm warnings. More brands offer ECGs for active AFib data, but you may not use them after getting one "normal" sinus reading; passive data is vital for making more people aware they should check their heart regularly, just like hypertension alerts point people toward using a BP machine.

It's clearer than ever that we're entering the medical era of wearables. Samsung is offering virtual doctor visits and prescription management, while the Pixel Watch 4 adds better temperature sensors to catch people "falling under the weather."

Apple's hypertension alerts are just the latest strike in this battle, but it's an impressive one. Knowing if you or loved ones are at risk for stroke, heart failure, or other conditions will intrigue a lot of people.