A prospective pilot study demonstrating non-invasive calibration-free glucose measurement

Glucose is an essential molecule in energy metabolism. Dysregulated glucose metabolism, the defining feature of diabetes, requires active monitoring to prevent significant morbidity and mortality. Current technologies for intermittent and continuous glucose measurement are invasive. Non-invasive glucose measurement would eliminate this barrier towards making glucose monitoring more accessible, extending the benefits from people living with diabetes to prediabetes and the healthy. We developed and investigated a spectroscopy-based system for measuring glucose non-invasively and without per-person calibration. Using data from a study including adults with insulin-treated diabetes, we constructed a computational model from a development cohort of 15 subjects and found a mean absolute relative difference of 14.5% in an independent validation cohort of five subjects. The correlation between the average model sensitivity by wavelength and the spectrum of glucose was 0.45 (p<0.001). Our findings suggest that spectroscopy-based non-invasive measurement of glucose without invasive calibration is possible.