While sitting down reading a book on the early afternoon of July 15, 2022, Nancie got an “alarming” message on her Apple Watch SE: “Your heart rate fell below 40 BPM for 10 min.” Despite feeling physically healthy, Nancie called her husband into the kitchen to show him the message.

Using their at home pulse oximeter and blood pressure devices, they checked Nancie’s oxygen levels, blood pressure, and confirmed her low heart rate.

To be safe, Nancie and her husband went to the local emergency room and texted their cardiologist. Nancie’s doctor diagnosed her with Bradycardia and told Nancie and her husband that, if Nancie wanted to live longer, she should receive a pacemaker implant to regulate her heart rate. The hospital placed Nancie in ICU for overnight monitoring, and the next morning their cardiologist put in the pacemaker

Nancie described her experience as “pretty incredible,” saying she “hadn’t realized the Watch would give you this message.”

As Nancie’s granddaughter, this story made me grateful that her Apple Watch prompted her to seek medical attention. As a law student interested in regulation of drugs and medical devices, this story made me reflect on the role of the FDA in the wearables space.

In this blog, I will discuss the some of the regulatory considerations for wearable devices. I will ask where these devices currently fit in the FDA regulatory framework and what technological or social developments could push the FDA to reconsider its position.

According to Section 201(h) of the Food, Drug, and Cosmetic Act a medical device is:

An instrument, apparatus, implement, machine, contrivance, implant, in vitro reagent, or other similar or related article, including a component part, or accessory which is:

(A) recognized in the official National Formulary, or the United States Pharmacopoeia, or any supplement to them,

(B) intended for use in the diagnosis of disease or other conditions, or in the cure, mitigation, treatment, or prevention of disease, in man or other animals, or

(C) intended to affect the structure or any function of the body of man or other animals, and which does not achieve its primary intended purposes through chemical action within or on the body of man or other animals and which does not achieve its primary intended purposes through chemical action within or on the body of man or other animals and which is not dependent upon being metabolized for the achievement of its primary intended purposes.[1]

 Based on this definition, Apple Watch functions, including heart rate monitoring, would appear to fit neatly within Section 201’s definition of a medical device because the functions can be used as part of diagnosing or preventing adverse heart events. Despite this fit, most Apple Watch functions are not squarely regulated as medical devices possibly because of the “general wellness exception.” The general wellness exception comes from a 2019 FDA guidance announcing they would not enforce medical device review procedures for low-risk devices with claims to improve “general wellness.”[2] They defined general wellness functions as those aiming to generally improve human function or general health without “making reference to diseases or conditions”[3]  As part of this guidance, the FDA provided examples for devices in this category and specifically named heart rate monitors for recreational activities.[4]

But this is not the end of the analysis because many wearable functions sit between general wellness and intended for use in diagnosis or prevention of disease. Even in Nancie’s case, the heart rate monitor did not diagnose the bradycardia, but it did significantly aid in the diagnosis by convincing her to seek additional medical attention.

Companies like Apple and Fitbit recognize the intermediate state their devices can have between general wellness and medical device and are seeking clearance to market wearables. Specifically, for new Electrocardiogram (ECG) and Irregular Rhythm Notification (Irnf) functions companies have requested market clearance for devices with a 510(k) submission. For this clearance, the company must demonstrate the device is as safe and effective as a substantially equivalent legally marketed device.[5] Apple has 510(k) clearance for the Watch ECG app, Irregular Rhythm Notification Feature (Irnf) and the Atrial Fibrillation History Feature.[6] Fitbit has also received similar clearance for the ECG and Irregular Rhythm Notification features of their smart watch.[7]

 To get clearance for these features that extend beyond general wellness, the companies had to compare their technologies to similar at-home devices and show they are comparably safe and effective. But wearables are becoming more ubiquitous in society and are getting more sophisticated with respect to health tracking. Is 510(k) clearance enough to keep consumers safe and what would push regulators to rethink their categorization and push for additional safety evidence or even full approval requiring robust human trials?

A timely example suggests that questions about oversight are coming sooner rather than later. Since 2013, Pulse Oximeters, including those intended for home use have been subject to 510(k) review.[8] After several years of researchers and doctors reporting that pulse oximeters are not as accurate for individuals with darker skin as they are for individuals with lighter skin, the FDA reviewed the technology and on November 1^st, 2022, held a public advisory meeting to discuss the issue and possible regulatory changes including studies demonstrating efficacy across user populations.[9] The FDA will continue accepting public comments on this issue until December 1, 2022, so it is worth following how pulse oximeter regulatory clearance or approval guidelines change in the coming years.

Pulse oximeter technology differs from the heart monitor functions in wearables, but this does not mean there are not equity problems in the application of ECG or Irnf in smart watches. Are readings equally accurate and are the devices equally effective at warning people of all races, ages, and genders? Like with pulse oximeters, the answers may take years of research, but the FDA and companies like Apple and Fitbit should think about potential concerns like this as wearables becomes more sophisticated, increase in their autonomous diagnostic capabilities or resulting data becomes increasingly used by doctors in clinics.

This summer Nancie’s Watch accurately measured her heart rate and likely saved her life, hopefully effective medical device development and safety regulation continues to produce such feel-good stories in the future.

 

[1] https://www.fda.gov/medical-devices/classify-your-medical-device/how-determine-if-your-product-medical-device

[2] https://www.fda.gov/media/90652/download

[3] https://www.fda.gov/media/90652/download

[4] https://www.fda.gov/media/90652/download

[5] https://www.fda.gov/medical-devices/premarket-submissions-selecting-and-preparing-correct-submission/premarket-notification-510k

[6] ECG – K201525, Irnf-  K212516, Atrial Fibrillation History Feature- K213971

[7] ECG- K200948, Irnf- –K212372

[8] https://www.fda.gov/regulatory-information/search-fda-guidance-documents/pulse-oximeters-premarket-notification-submissions-510ks-guidance-industry-and-food-and-drug

[9] For more information see McFarling, U.L., Pulse oximeters and their inaccuracies will get FDA scrutiny. What took so long?, STAT, Nov. 1, 2022, https://www.statnews.com/2022/11/01/pulse-oximeters-inaccuracies-fda-scrutiny/ and https://www.fda.gov/advisory-committees/advisory-committee-calendar/november-1-2022-anesthesiology-and-respiratory-therapy-devices-panel-medical-devices-advisory#event-materials