Comparison of oximetry event desaturation transient area-based methods in predicting cardiovascular disease mortality outcomes

Desaturation area-based parameters derived from oximetry have recently emerged as novel predictors of cardiovascular disease (CVD) mortality in the context of obstructive sleep apnoea (OSA). Various published calculation methods exist for event desaturation transient area calculation. The published methods differ in how they calculate the sampling window, and how they calculate the baseline. This study aims to evaluate the six possible combinations of baseline (event-specific, record-specific, or fixed) and sampling window (record-specific or fixed) to find an easy-to-calculate yet effective method area for predicting CVD mortality. The Sleep Heart Health Study data and corresponding CVD mortality outcomes were utilized. The predictive performance of each method was assessed by Cox proportional hazard regression analysis with adjustment for relevant covariates. Results show that an area method using a record-specific baseline and a fixed sampling window and an area method using a record-specific baseline and sampling window performed the best.