477 Association between Nocturnal Hypoxemic Burden and Glucose Metabolism

Abstract

Abstract Introduction To evaluate the association between a novel integrated event-based and hypoxemia-based parameter of polysomnography (PSG), hypoxemic load or HL100, and fasting blood glucose (FBG) and hemoglobin A1c (HbA1c) levels. Methods Adult patients, who underwent an in-lab PSG at University of Iowa Hospitals and Clinics with FBG or HbA1c levels were included. Event-based parameter and hypoxemia-based parameter data were derived. HL100, defined as an integrated area of desaturation under 100% oxygen saturation curve during the total sleep time divided by the total sleep time, was calculated by Python software version 3.8.5. Demographic data and glycemic parameters within 1 year prior to PSG(FBG and HbA1c) were retrieved from chart review Spearman correlation analysis and stepwise backward regression analysis were performed to determine independent predictors of FBG and HbA1c levels. Results Of the 467 patients underwent an in-lab PSG, 385 had FBG levels and 239 had HbA1c levels. All event-based and hypoxemia-based parameter; including HL100, were significantly correlated to FBG and HbA1c levels. Stepwise backward regression analyses, adjusting for age, sex, body mass index and diabetes status, revealed that log HL100 was significantly related to FBG (B=20.8, p=0.015), and log oxygen desaturation index was found related to HbA1c levels (B=0.273, p=0.037). Other parameters (e.g. apnea hypopnea index, minimum oxygen saturation) were not independently associated with glycemic parameters. Conclusion HL100 showed a significant positive correlation with FBG and HbA1c levels and only log HL100 was an independent predictor for FBG levels. This might imply that any degree of desaturation below 100% could result in adverse glucose metabolism. HL100 might be useful for interpretation of sleep studies, risk stratification and patient management purposes in the future. Support (if any):