The holy grail for some wearable developers is a non-invasive and reliable means of measuring blood glucose levels. Researchers are working on optical sensors and other systems to achieve this. In the meantime, an intermediate solution may be readily available.

Scientists at Radboud University in the Netherlands have found that an off-the-shelf wearable heart rate monitor can identify hypoglycemic events for Type 1 diabetes patients. Using a wearable, wireless sensor patch from VitalConnect, they found that changes in heart rate variability (HRV) can signal when a body is experiencing low blood sugar. HRV is a measure of the beat-to-beat timing variation. They also found that heart rate tended to increase during a hypoglycemic event. In a paper presented at the Endocrine Society’s ENDO2018, they reported that their algorithms detected hypoglycemic events 72% of the time. They also found that these indicators were present before the event would show up on a traditional finger-stick blood sample.

The researchers were not satisfied with identifying fewer than three out of four events, and so are working to further refine their algorithms in order to increase the system’s accuracy. Their goal is to create an unobtrusive way for Type 1 diabetes patients to get alerts when their blood sugar levels fall too low.