Diabetes is a dreadful disease that effects nearly every system of the body, most notably the kidneys, eyes, peripheral nerves and the circulatory system. There are two varieties of diabetes, Type 1 (genetic – usually expressed early in life), and Type 2 (acquired – largely diet-related), and both involve an inability of the pancreas to produce adequate levels of insulin, which controls the body’s glucose (sugar) levels. The causes of Type 2 are varied, but mostly involve a combination of genetic predisposition, excessive body weight, poor nutrition and physical inactivity. Advanced stages of the disease often lead to blindness, lack of sensation in the limbs which in turn leads to pressure ulcers, compromised circulation leading to amputation, and end stage renal (kidney) disease requiring dialysis or, if the patient is lucky, a kidney transplant. As of 2020, 463 million adults were living with diabetes and 374 million people were at risk for developing the disease (prediabetic).
Managing diabetes involves, depending upon disease severity, diet control, exercise, oral medications and daily insulin injections. The goal of the latter is to maintain a stable and acceptable level of blood glucose throughout the day. In order to accomplish this, an individual must periodically measure his/her blood glucose levels in order to optimally balance the frequency and dosage of insulin injections. On a day-to-day basis, this typically involves pricking one’s finger and then applying a drop of blood to a paper strip which is inserted into a small electronic device (a glucometer) that generates a blood glucose value. Given the repetitive nature of this painful exercise, there is great interest in an effective measurement alternative. One such alternative is the continuous glucose monitor (CGM), which is a small device containing an electrode sensor inserted into the skin for 2 weeks at a time (usually in the upper arm) and a transmitter to relay the numeric readings to a peripheral device like a smartphone. This device in turn could be integrated with an insulin pump to precisely balance the body’s insulin levels. An example of a CGM is the Free Style Libre.
It shouldn’t be surprising that the holy grail for monitoring glucose levels would be a non-invasive glucometer, which would enable a painless, on-demand (or continuous) glucose measurement. Such a device would facilitate the precise management of the disease, which would likely prevent or delay the onset of the serious health complications previously mentioned. Unfortunately, the development of this technology is easier said than done. Complicating factors include population variance in skin thickness, soft tissue, fat, and the size and depth of blood vessels.
There have been many attempts to develop a non-invasive glucometer over the last 50 years, applying diverse measurement techniques including bioimpedance spectroscopy, microwave/RF sensing, fluorescence technology, infrared and near-infrared spectroscopy, optical coherence tomography, optical polarimetry, raman spectroscopy of the interstitial fluid, reverse iontophoresis, and ultrasound technology. Experimental devices range from handheld and wearable appliances to patches and contact lenses. With respect to the latter, many scientists have turned their attention to targeting the eye for measurement as opposed to the skin, as there is easier access to glucose-containing bodily fluids (tears) and less anatomical variance from person to person.
Which brings us to today . . .
Looking through a lens made from a very large grain of salt, there are three recent commercial initiatives in particular that I believe warrant our attention. The first is from Rockley Photonics, a company that offers advanced health monitoring technology for smart watches, including those from Apple (which invested at least $70 million in the company). They are using infrared technology, which they claim is up to one million times more accurate than the LED technology used in smartwatches today and can perform continuous monitoring of numerous biomarkers such as hydration, blood pressure, core body temperature, lactate, and glucose levels. www.rockleyphotonics.com
A second offering is from Know Labs. They claim their non-invasive Bio-RFID sensors (using radio waves) can identify different molecules in the body, such as glucose, oxygen, alcohol and metabolized drugs. The company says it will be available in both wearable and small handheld forms. www.knowlabs.co
Finally, an Israeli startup, Hagar Tech, is similarly using radio frequency wave and AI technology to measure glucose under the name G-Wave. They claim the accuracy is 95% compared to off-the-shelf handheld finger prick devices currently in use. www.hagartech.com
On the surface, all three of these initiatives sound promising, especially given Apple’s substantial investment in the category. Still, considering the long history of failed attempts and the associated hundreds of millions of dollars spent on R&D, only time will tell if all or any of them will prove successful and become commercially viable. But if the grail is finally realized (nod to Harrison Ford), the amount of reduction in suffering, and the number of lives saved, would be incalculable. If you’re looking for a striking example of a game changer, this would be it.