Healthcare costs continue to escalate at breakneck speed, driven mostly by the fact that we don’t catch the warning signs of medical issues until they have manifested themselves in disease or injury. These issues sometimes necessitate costly hospital stays and long-term therapies. In fact, those costs are so staggering that the United States Government is setting aside $215 million in Fiscal Year 2016 for an effort called the Precision Medicine Initiative which, amongst its many study topics, will fund research into collecting and analyzing “...lifestyle data, such as calorie consumption and environmental exposures tracked through mobile health devices, [which] will help researchers understand how genomic variations and other health factors affect the development of disease.” In other words, can we identify ways through the use of medical wearable technology to do more preventative care that is targeted to a specific individual's pre-existing medical conditions, lifestyle behaviors, and environment?
Today’s health and/or fitness trackers are but a prelude to much more interesting devices that will go beyond step counting and heart rate monitoring. The fitness wearables commercially available today are nothing more than fancy electronic pedometers that have been around for roughly 30 years, with the added pizazz of wireless connectivity to send data to the cloud. Nice features for sure, but they don’t add much in the way of medical usefulness. Furthermore, while there are many FDA-approved medical devices on the market today, such as insulin monitors and blood pressure monitors, these items perform a single function and most could hardly be described as “wearable”. Done right, next generation medical wearables might just prove to be the key catalyst for revolutionizing how healthcare is delivered.
Determining the overall health of the human body is a complicated matter that must account for dozens of indicators, including vital signs (blood pressure, heart rate, and oxygen levels), fitness behavior (distance walked and amount of time sedentary), and more complex analysis of internal organs and systems to include blood cell counts, blood glucose, etc. Fortunately there is a lot of work occurring to shrink and converge medical-related sensors into inexpensive tools.
Engineers and physicians at Johns Hopkins University recently announced a prototype called MouthLab, which is a small device that uses a mouthpiece and thumbpad sensor that can quickly collect vital signs. In addition, they aim to use chemical cues from blood, saliva, and one’s breath to detect markers for other serious medical conditions including blood glucose levels for diabetics, kidney failure, and oral, lung, and breast cancers. Meanwhile, Caltech researchers have been working on ways to shrink the technology that analyzes the body's white blood cell count. Leukocytes are the immune system's fighters and elevated levels are an indication that the body is fighting a disease. Unfortunately, traditional methods require vials of blood and days of analysis, but Caltech is perfecting technology that can do the same job in minutes with just a pin prick.
If the size and cost reduction principles of Moore’s Law even loosely apply to medical wearables, then it won't be long before we see devices packed with health-related sensors. It is speculated that the first generation Apple Watch was to include upwards of ten health related sensors to track everything from blood pressure, to analyzing the wearer’s stress. It is further believed that a combination of technical and regulatory challenges were encountered and thus many sensors were abandoned for the inaugural product launch. Even with such difficulties, many companies are seeking to bring medical wearables to market as they are finding the potential financial and health benefits to be too tempting to ignore.
The ability for a single device to track as many different data points is going to be key, as only the most devout believers of the “quantified self” are willing to strap on and charge multiple wearables in order to track all of the necessary health data to be medically useful. A logical solution would be to create a modular system whereby different watch bands could have different sensor suites depending on the medical data points that need to be monitored. Perhaps wearables could be coupled with a “SmartPill” that is swallowed and then transmits its findings back to your medical wearable as it tours your internal plumbing.
Battery life is another key design aspect that will need to be improved compared to today's standards. Medical wearables will not have the luxury of today's smartwatches in which we typically assume that the wearer will be happy to allow their device to recharge while they are sleeping. Medical-focused devices will have many use cases where the primary focus is the individual's health status while they are asleep; thus having to be removed from the wearer’s body will simply not be an option. Perhaps energy harvesting technology will be built that can leverage a user's radiated body heat or physical movement to provide enough power to at least enable sensors and data recording.
Wireless connectivity is another area that, upon initial glance, seems inconsequential given the proliferation of 4G cellular data and Bluetooth enabled smartphones. Many fitness trackers today rely on a Bluetooth connection to a smartphone for data transfer, and more robust medical wearables may have to account for scenarios where the user does not have such connectivity. If we assume that medical wearables do strike a balance between ease of use and usefulness for complex healthcare applications, then we might find wearables widely used in assisted living and elderly care facilities where access to smartphones is not a guarantee.
Michael Parks, P.E. is the co-founder of Green Shoe Garage, a custom electronics design studio and embedded security research firm located in Western Maryland. He produces the Gears of Resistance Podcast to help raise public awareness of technical and scientific matters. Michael is also a licensed Professional Engineer in the state of Maryland and holds a Master’s degree in systems engineering from Johns Hopkins University.