Validating a non-invasive diagnostic for sustained hyperglycemia in humans based on W-band spectroscopy

Diagnosis of sustained hyperglycemia is a critical factor in diabetes care. HbA1c is the current gold standard indicator assessing fluctuations in medium/long term glycemic state. In this work, W-band spectroscopy is tested for non-invasive monitoring of sustained glycemia by a preliminary validation diagnostic study, using HbA1c indicator as reference. W-band transmission profiles (amplitude) of 30 subjects were longitudinally observed over a period of 7 months. Collected spectral data is studied using supervised longitudinal functional data analysis methods. Results support that it is possible to predict HbA1c value by using W-band transmission profiles, with an excellent linear response (R-squared = 0.97).