Improving the Cardiovascular Outcomes of Obstructive Sleep Apnea: Towards More Precise Hypoxia-Based Models of Disease Severity

Obstructive sleep apnea (OSA) affects at least 1 billion people worldwide, and its increasing prevalence is alarming considering an association to comorbidities such as cardiovascular disease (CVD) and to demonstrated health disparities. This raises concerns regarding the current diagnostic standards, which are also impacted by disparities. The current review was aimed at identifying limitations in the apnea-hypopnea index (AHI), the primary clinical indicator of OSA severity, and analyzing recent alternatives. In addition, the association between OSA and CVD was discussed, and, considering the role of intermittent hypoxia, solutions were proposed for improving OSA diagnosis. Based on a review of current literature, alternative metrics to the AHI such as the hypoxia burden, sleep apnea-specific pulse rate, and oxygen desaturation rate were shown to be correlated with indicators of CVD in OSA patients. A recent mathematical study also presents the possibility of a model-based metric to eliminate existing bias in diagnostics and provide a more accurate quantification of tissue hypoxia. The analyzed studies give incentive to look beyond current clinical standards in OSA. Through this review, we motivate the use of mathematical modeling as a future avenue to improve OSA diagnosis with a hypoxia-based approach.