Article: Establishing Trust in Wearable Medical Devices

Many of the topics covered in this article I have covered in this blog. Most recently, my discussion of signal detection and the Apple Watch (https://medicalremoteprogramming.blogspot.com/2019/12/signal-detection-and-apple-watch.html) that I suggest that you read after reading this article from Machine Design.

Here's the link to the article: https://www.machinedesign.com/medical-design/article/21122718/establishing-trust-in-healthcare-wearables?utm_source=MN+MD+Medical+Design&utm_medium=email&utm_campaign=CPS200206038&o_eid=7596G0176945B2B&rdx.ident%5Bpull%5D=omeda%7C7596G0176945B2B&oly_enc_id=7596G0176945B2B

Here are a few quotes from the article.

To say that we can get personal health insight from continuous monitoring presumes a “chain of trust.” In other words: 

• The interpretation of any data must not only be accurate but reliable. The challenge lies in handling “borderline” data. Any interpreting strategy or algorithm faces data sets that it finds ambiguous. For an algorithm to be reliable, users must be able to quantitatively understand its detection limits and error characteristics.

• The data and/or its interpretation must reliably reach the decision-maker for it to become actionable.

• The data must be correctly associated with historical records of the patient for it to have context.

• The data must be proven to be authentic to trigger any meaningful action.

However, using clinical equipment to capture vital signs that are representative of the wearable use cases is often difficult and sometimes inaccurate. To avoid a rash of false positives or false negatives, one must carefully select the population of test subjects and carefully develop the representative use cases. It’s also important to compare data from the patient’s own history or baseline, keeping in mind that this baseline isn’t static as the patient ages and undergoes other changes.

Apple Watch 5: Heart Monitoring Capabilities -- Afib

The Apple Watch 5 has a heart rhythm monitoring capability that is tuned to detecting the presence of atrial fibrillation, AKA, Afib. Apple categorically states that the watch is unable to detect a heart attack. (And by implication, the likelihood of a heart attack occurring within minutes or hours.)

You have to manually enable your heart monitoring system (Watch and iPhone) to detect Afib. This not part of the default configuration. Here's the link for setting it up: https://support.apple.com/en-us/HT208931#afib

Here's what Apple says about the capabilities of their system and note that it requires both the Apple Watch 5 and an iPhone: 

INDICATIONS FOR USE (NON-EU REGIONS)

The Irregular Rhythm Notification Feature is a software-only mobile medical application that is intended to be used with the Apple Watch. The feature analyzes pulse rate data to identify episodes of irregular heart rhythms suggestive of atrial fibrillation (AF) and provides a notification to the user. The feature is intended for over-the-counter (OTC) use. It is not intended to provide a notification on every episode of irregular rhythm suggestive of AF and the absence of a notification is not intended to indicate no disease process is present; rather the feature is intended to opportunistically surface a notification of possible AF when sufficient data are available for analysis. These data are only captured when the user is still. Along with the user’s risk factors, the feature can be used to supplement the decision for AF screening. The feature is not intended to replace traditional methods of diagnosis or treatment.

The feature has not been tested for and is not intended for use in people under 22 years of age. It is also not intended for use in individuals previously diagnosed with AF.

INTENDED PURPOSE (EU REGION)

Intended Use

The Irregular Rhythm Notification Feature (IRNF) is intended to pre-screen and notify the user of the presence of irregular rhythms suggestive of atrial fibrillation (AF). The feature can be used to supplement a clinician’s decision to screen for possible AF. The feature is intended for over-the-counter (OTC) use.

The feature has not been tested for and is not intended for use in people under 22 years of age. It is also not intended for use in individuals previously diagnosed with AF.

Indications

The feature is indicated to pre-screen for irregular rhythms suggestive of AF for anyone aged 22 years and over.

USING THE IRREGULAR RHYTHM NOTIFICATION FEATURE Set-Up/On-boarding

• Open the Health app on your iPhone.
• Navigate to “Heart”, then select “Irregular Rhythm Notifications”.
• Follow the onscreen instructions.

Receiving a Notification

Once the feature is turned on, you will receive a notification if the feature identified a heart rhythm suggestive of AF and confirmed it on multiple readings.
If you have not been diagnosed with AF by a GP, you should discuss the notification with your doctor.

All data collected and analysed by the Irregular Rhythm Notification Feature is saved to the Health app on your iPhone. If you choose to, you can share that information by exporting your health data in the Health app.

SAFETY AND PERFORMANCE

In a study of 226 participants aged 22 years or older who had received an AF notification while wearing Apple Watch and subsequently wore an electrocardiogram (ECG) patch for approximately one week, 41.6% (94/226) had AF detected by ECG patch. During concurrent wear of Apple Watch and an ECG patch, 57/226 participants received an AF notification. Of those, 78.9% (45/57) showed concordant AF on the ECG patch and 98.2% (56/57) showed AF and other clinically relevant arrhythmias. A total of 370 irregular rhythm notifications with readable ECG patch data was received by the 57 participants. Of those 370 notifications, 322 (87.0%) were assessed to be AF, 47 (12.7%) were arrhythmias other than AF and 1 (0.3%) was sinus rhythm. These results demonstrate that, while in the majority of cases the notification will accurately represent the presence of AF, in some instances, a notification may indicate the presence of an arrhythmia other than AF. No serious device adverse effects were observed.

CAUTIONS

The Irregular Rhythm Notification Feature cannot detect heart attacks. If you ever experience chest pain, pressure, tightness or what you think is a heart attack, call emergency services.

The Irregular Rhythm Notification Feature is not constantly looking for AF and should not be relied on as a continuous monitor. This means the feature cannot detect all instances of AF and people with AF may not get a notification.

• Not intended for use by individuals previously diagnosed with AF.
• Notifications made by this feature are potential findings, not a complete diagnosis of cardiac conditions. All notifications should be reviewed by a medical professional for clinical decision making.
• Apple does not guarantee that you are not experiencing an arrhythmia or other health conditions even in the absence of an irregular rhythm notification. You should notify your GP if you experience any changes to your health.
• For best results, make sure your Apple Watch fits snugly on top of your wrist. The heart rate sensor should stay close to your skin.

From the information provided I am unable to determine how the Afib monitoring system detects Afib. It does seem use an additional capability beyond heart rate system, but from what little I can understand, it uses software running on either the watch and/or the iPhone and uses as input the data from the heart rate system.

I have no idea what algorithms the Apple heart monitoring system is using to detect atrial fibrillation (AF), but if you read the study above, you'll note that apparently, the Apple system has significant false positive rate. Walking through the study, to qualify as a subject for the study, you had to have had a positive indication of AF by the Apple system. That's the one clear message from the study. Another clear message is that both the Apple system and the AF patch can detect heart arrhythmia  other than AF, but what those were is unclear. Unfortunately the way the data is reported does not provide full clarity into the procedure and results. So there's not much more that I can comfortably conclude.

I feel comfortable stating that if you're wearing the Apple Watch and using the AF detection system and you get an AF indication, it's worth your time to get it checked out even knowing full well that the indication is more than likely to be a false positive.

However, high AF false positive rate of nearly 60% is concerning from the standpoint of those who have the Apple AF detection system activated and receive false positive indications. Information like this gets around and users may have tendency to ignore the AF indications when in fact they should be paying attention to them. To curb the possibility that someone ignores an accurately reported AF indication from the Apple system, it would behove Apple to include with the AF notification a check list displayed on the iPhone the walk the user through to determine if in fact this is an AF event.

Article: Year of Telehealth

Here's an article telling us what lots of us already have learned, that telehealth is an up a coming method of providing effective and cost-effective as well as continuous medical care where ever a patient may be. Here's the link to the article: https://www.beckershospitalreview.com/telehealth/dr-toby-cosgrove-2019-will-be-the-year-of-telehealth.html

Here's a quote from the article that I think is of interest:

"[Oakland, Calif.-based Kaiser Permanente] is seeing over 50 percent of their patients distantly," Dr. Cosgrove told CNBC.

What Cosgrove isn't telling us is how telehealth is being provided. Telehealth is pretty loosely defined. It can mean that patients have access to a health care provider through chat or the telephone. Or it can mean something more sophisticated such as continuous medical-device communication and automated monitoring. One way or another telehealth is clearly on the rise and will likely become the standard for providing care.

Careband: Keeping track of those with dementia

I was at an evening venture capitalist meeting on 13 November 2018. I'm not a venture capitalist but I have a few connections to this community and I periodically receive invitations to their meetings. Most of the time I pass on attending. I'm interested in science, mathematics and technology. VCs are interested in ways to make money. Nothing against them. We just live on different planes of existence.

However, I attended this meeting because I read the description of one of the companies doing a presentation, careband (http:www.careband.co).

careband

Careband provides a capability to track the location of people with dementia. This is a more difficult problem than you might imagine. In institutions, patients with dementia are known to wander away: from the institution, from their homes, from family members. The patients do not know where they are or how to return. Institutions who care for dementia patients frequently need to find their patients who have wandered away from the institution's grounds or to areas of the institution that caregivers do not expect that they would be able to wander. 

Thus there's a clear need to be able to keep contact track of dementia patients. To know where their location at all times and be notified when they've wandered off the grounds of the institution.  Here's a page from the careband.co website that summarizes the capabilities of their system.

The diagram above shows the elements of system for patients and customers/caregivers -- those responsible for caring for the dementia patient(s). Caregivers can see at a glance the current location of each patient. Each dementia patient wears a band about the size of a large wristwatch on the wrist that periodically sends a location related message to the network. All data is sent to careband's cloud server system. Patient location data is made accessible to the caregiver systems that are connected to the cloud server system.

The wrist bands connect to the Internet to the low-power communications system: LoraWAN. More information about this wireless data communications network is available here: https://lora-alliance.org/about-lorawan The LoraWAN network is a low-power, low-speed (0.3 kbps to 50 kbps) but long distance (up to 3 miles from an access point outside) and robust wireless communications system. 

The wristband also includes Bluetooth that is used to provide indoor location data. And an accelerometer has been included to provide information regarding whether the patient has moved his or her body during the reporting period. 

I am not familiar with all of the current capabilities of the careband.co system. However, I know that the wristband continually transmits to the cloud the following data:

• Patient ID data
• Transmission time 
• Location data
• Movement (whether or not the person has moved from the time of the last data transmission and the time of the current data transmission)
• Battery charge level

How careband.co is currently analyzing is something of which I am presently unsure, but there are a number of pieces of information that can be derived from this relatively small amount of data. Here's what's possible:

1. Current patient location
2. Map of patient's activity and the distance covered over time
3. Amount of time that the patient was moving
4. Alarm initiation: should the patient stray away from the institution, the system can automatically notify the caregivers. (Boundaries should be able to be drawn on the display.)
5. Trend and trend line analysis for patient activity time and distance covered. These could be indicators of the patient's cognitive health. Significant deviations from calculated trend lines could be indicators of a slip or improvement in a patient's cognitive and/or physical health.
6. Suggest that the patient has removed the band from his or her wrist (when the patient appears not to have moved during normal activity time) or that the patient maybe in distress or died.

There could be more information that can derived from the wristband data that I have yet to think of. As I come up with additional thoughts regarding this, I shall post them.

Upgrades to the wristband could include pulse oximetry and pulse rate data. Again, there are other capabilities that could be added that I have yet to think of.

Since the transmission speed is so low, careband.co will likely need to develop a data compression system to effectively communicate this data back to the cloud server system. 

Careband.co is one more interesting product for remote medical monitoring. It's not designed for remote patient management largely because most patients will normally be closely supervised. However, it could be an aid to enable people with dementia to live for a longer time in their own homes. The benefits to both the patient and to society are massive. Six months to a few years of being able to live in one's own home would improve both the quality of life for people with dementia and significantly, dramatically reduce the cost of care.

I shall continue to monitor careband.co's progress. Stay tuned.

Careband.co plans on making their products available through medical device distributors. Their products are not yet commercially available. They are about to manufacture the wristband. Their wristband has been approved by the FCC. FDA approval is not required.  If you are interested in purchasing their product, please contact them at care band.co.

I should mention that careband.co is looking for investors. If you're interested in what careband.co is selling, please contact them directly using the URL listed above.

Apple Watch: An Emergent Medical Monitoring Device?

Apple has been grappling with the design and capabilities of a smart watch for years. Apple CEO Tim Cook announced that Apple would produce a smart watch in September 2014. The initial rollout is scheduled for 25 April 2015.

Tim Cook has suggested that the Apple Watch would do more than provide its owner with the time and as a wearable means to communicate with your iPhone ... something that you would rather leave in your pocket or purse. He suggested that this device could also serve as a means to assist people with monitoring their health and fitness. But can this device that is strapped to your wrist really do that?

Research on Smart Watches and Their Owners

Before doing the deep dive into the Apple Watch, I want briefly discuss some of my experience with researching smart watches. I can't divulge all the details of that research because some of that work that I was part of a research team is proprietary. I can say a few things about smart watches, the variety of their capabilities and some of the opinions about them that people who have used them have provided.

The smart watches that we used in our research had capabilities that fell into two categories. The first were capabilities that allowed the owner to communicate with and control their smartphone. For example, a smart watch would allow an owner to control music or podcasts being played or allow the owner to make and receive calls through the smart watch. Communication between the two devices was over Bluetooth (IEEE 802.15.1) The second were independent capabilities this can include GPS map capabilities, collecting and displaying running or cycling distances and routes. And providing the date and time.

We found that owners of smart watches were initially excited and enthusiastic about owning a smart watch. However, over time that excitement and interest disappeared ... and disappeared to the point where most owners were considering ways to rid themselves of their smart watches. Based on our research, smart watches seemed like a good idea. But once initially-enthusiastic owners tried to incorporate smart watches into their lives, their response to them became negative.

Apple Watch

The Apple Watch is almost upon us with great fanfare. Based on photographs and my read of the hardware and descriptions of the Apple Watch, it appears to be stylish that its predecessors ... an important quality. It appears that it will have many of the same capabilities as it's predecessors as well ... the ability to communicate with and control the owners iPhones (5 or later) - the smart watch will have Near Field Communication (NFC), Bluetooth (4.0), a speaker, microphone and a touch screen to enable communication and control - and a number of independent capabilities based on the following embedded sensors: accelerometer, gyroscope, heart rate sensor and barometer.

Beyond the heart rate sensor, what else might make the Apple Watch a wearable system to assist people with their health and fitness? I'm not sure, but what I found interesting about the Apple Watch, what makes it potential game changer in the realm of health and fitness is this: WiFi (802.11 b/g/n).

From all that I can tell, the inclusion of WiFi could be something that might make the Apple Watch something significant with respect to means for medical monitoring. WiFi is different from Bluetooth in that Bluetooth creates a dedicated one to one communications channel. A WiFi access point (AP) can support multiple, simultaneous connections. Is Apple working with other companies to create new body sensors that can communicate with the Apple Watch using WiFi? It's plausible and well worth watching. 

Monitor this blog ... more on this to come.