Showing posts with label Physiological Sensors. Show all posts
Showing posts with label Physiological Sensors. Show all posts

Tuesday, December 10, 2019

New Wearable Sensor Detects Gout and Other Medical Conditions

I just came across this article regarding a wearable sensor systems and thought that I would share it. This could be a component in a remote monitoring system. The sensor's information source is the person's sweat. "Sensor can pick up small concentrations of metabolites in sweat and provide readings over long periods of time." To turn this into a remote monitoring system, all that's required is a means to transmit the data over wireless. 

From the article:

The team’s goal is a sensor that lets doctors continuously monitor the condition of patients with illnesses such as cardiovascular disease, diabetes, and kidney disease, all of which put abnormal levels of nutrients or metabolites in the bloodstream. Patients would be better off if their physician knew more about their personal conditions and this method avoids tests that require needles and blood sampling.
“Such wearable sweat sensors could rapidly, continuously, and noninvasively capture changes in health at molecular levels,” Gao says. “They could make personalized monitoring, early diagnosis, and timely intervention possible.”

Monday, November 18, 2019

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.



Friday, September 14, 2018

Apple Watch 4 -- FDA Announcement: Statement from FDA Commissioner Scott Gottlieb, M.D., and Center for Devices and Radiological Health Director Jeff Shuren, M.D., J.D., on agency efforts to work with tech industry to spur innovation in digital health

The FDA just provided what amounts to a "shout-out" to companies that design and manufacture intelligent, wearable devices that include medically-related monitoring devices and specifically, the Apple Watch 4.

Here's the link to the FDA statement: https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm620246.htm

And here's an interesting quote from the announcement:

... [There have come] a new swath of companies that are investing in these new opportunities [e.g., wearable, intelligent monitoring devices measuring medically-related, physiological characteristics with analysis capabilities.] These firms may be new to health care products and may not be accustomed to navigating the regulatory landscape that has traditionally surrounded these areas. A great example is the announcement of two mobile medical apps designed by Apple to work on the Apple Watch. One app creates an electrocardiogram, similar to traditional electrocardiograms, to detect the presence of atrial fibrillation and regular heart rhythm, while the other app analyzes pulse rate data to identify irregular heart rhythms suggestive of atrial fibrillation and notify the user. The FDA worked closely with the company as they developed and tested these software products, which may help millions of users identify health concerns more quickly. Health care products on ubiquitous devices, like smart watches, may help users seek treatment earlier and will truly empower them with more information about their health.

---------------
I find it interesting that Dr. Gottlieb states that the Apple Watch analyzes pulse rate data, not the ECG, to detect "rhythms suggestive of atrial fibrillation." Yeah, that's a way to do it, but analysis of the ECG is a much better way. When I do a deep dive on the Apple Watch 4, I'll look into this and questions like it.


Tuesday, March 24, 2015

Benefits of Remote Monitoring & Mayo Clinic Announcement

I've been arguing for some time that remote monitoring can not only lower medical costs, but it show itself to be of benefit to the patient as well. Here's an article that not only shows that remote monitoring can be of benefit to the patient, but to the physician as well.

Remote monitoring can not only provide better and more data ... that can lead to better analysis and conclusions. It can provide that data to the physician before the patient comes in for a visit. Furthermore, if an adverse medical event occurs, that data is captured and available to the attending health care providers. Admittedly the patient would have needed to have been wearing the monitoring device at the time, but if the person was wearing the monitoring device that information would be available.

Here's the link to the article: http://www.healthcareitnews.com/news/remote-patient-monitoring-steps-toward-new-era

Here are a few quotes from the article that I found interesting ...

... if you spend $100 a month to monitor patients remotely – over a year it would cost much less then what you would pay if they have to come back to the hospital.


[T]here are two waves of activity. The more traditional top down wave extends the reach of hospitals with FDA approved medical devices that are deployed out in the home by providers by doctors to keep track of these patients.
There is also an increasing consumer wave where people are going out and buying the sensors and devices on their own and tracking their fitness and health and bringing that information to their healthcare providers.
=== I find this quote interesting in light of the Apple Watch and other similar devices ======
Some physicians, Kleinberg asserted, don’t need and don’t want that data from the patient and claim that they don't have a place to put the data and they don't have time to look at it.
=== Actually, machines can monitor this data on a continual basis. The machines can alert physicians as needed and provide summaries. Physicians need not review raw data. ======
"There's a push back to this consumer-up bottom-up wave. But over time I think we're going to see that the sensors and the data that’s coming from these devices is going to have more and more value and providers are going to put more faith in it," said Kleinberg. "They're going to look at it and make some sense of it and part of the way they are going to do that is if they have more confidence about that data."
=== I think the last sentence may be one of the most significant in the article. Confidence in the data and automated analysis will build and become mainstream. And I think that cost considerations will be a factor. =====

Announcement Title: Mayo Clinic To Develop Wireless Sensors To Treat Obesity

I found this quite interesting when I came across it. The sensors are far from being developed but I thought it worth posting the announcement link.


Here's a quote from the announcement.

The goal is to produce the first wearable patch sensor – the size of a bandage – that is wireless, disposable, and can remotely monitor patient movements via smartphone. This new technology would simplify tracking with greater accuracy of patients and clinical trial subjects for whom a certain level of activity is prescribed to achieve their goals.

Monday, March 23, 2015

More on Apple Watch as a Medical Monitoring Device

I recently ran across an article about Apple's continuing work to make the Watch a medical monitoring device. Here's a link to that article:
http://appleinsider.com/articles/15/02/16/apple-scrapped-advanced-apple-watch-health-monitoring-features-due-to-reliability-issues

According to the article Apple considered including a number of medical monitoring devices/capabilities for their first generation Watch. For the first generation, those have been scrapped for reliability and regulatory reasons. Apparently Apple is still interested in adding more physiological sensors to the Watch, but if those capabilities appear, they'll be included in next generation Watches.

However, there was something that caught my interest from the article:

"Aside from catchall smartwatch devices, a number of standalone solutions for off-the-shelf medical style monitoring already exist in the form of products — usually wrist-worn — from smaller manufacturers and startups. For example, the W/Me band incorporates a specialized sensor to measure a user's autonomic nervous system for keeping track of stress levels, while the latest products from Fitbit tout all-day heart rate monitoring."


There are lots of other companies making sensors that would be useful for medical monitoring purposes. For Apple and the Watch there are many ways this can play out. Frankly none of these are mutually exclusive.

  1. Apple can purchase the sensing technology to incorporate into Apple-produced sensors.
  2. Apple can purchase the sensors and integrated them into the Watch 
  3. The third-party sensors can communicate with the Apple Watch over WiFi. 
The data collected by the Apple Watch could be:

  1. Analyzed and presented locally ... by the Watch
  2. Uploaded to the iPhone were the iPhone would process the data and either communicate it back to the Watch for display or be displayed on the iPhone ... or both.
  3. Uploaded to the iPhone that intern uploads it to a centralized system for processing. The results of that analysis could be communicated back for display on the iPhone or Watch. If so indicated an alert could be included if conditions warranted. 
Again, none of these are mutually exclusive. Data could be processed and displayed on the Watch and communicated back to a centralized system.

More updates on the Apple Watch to come ...