Evaluating the clinical value of the hypoxia burden index in patients with obstructive sleep apnea

ABSTRACT

Purpose: We aimed to develop a novel index, the hypoxia burden index (HBI), that reflects the degree and duration of oxygen desaturation, and to determine whether this index is better than the apnea hypopnea-index (AHI) for evaluating obstructive sleep apnea (OSA) and cardiovascular diseases morbidities.

Methods: We retrospectively analyzed 459 adult subjects who underwent overnight polysomnography (PSG) in this study. The HBI was calculated by dividing the total desaturation area of SpO₂ below 90% by the TST measured in seconds. Correlations between the HBI and PSG parameters and the cardiovascular diseases (CVDs) of inpatients were explored.

Results: For the 459 participants, the HBI was highly correlated with the AHI (r = 0.690), lowest oxygen saturation (SpO₂min) (r = −0.733), and proportion of cumulative sleep time with SpO₂ below 90% in total sleep time (TST) (CT90%) (r = 0.801). The HBI was mildly correlated with Epworth sleepiness scale score, morning systolic blood pressure, diastolic blood pressure, and mean arterial pressure. Among the significantly different parameters in the CVD and non-CVD groups in 202 inpatients (age, sex, the longest time of apnea, AHI, and HBI), only age, sex, and HBI [OR 1.006 (1.001–1.011), p = 0.021] were independently correlated with CVDs.

Conclusions: The HBI considers both hypoxia duration and severity during sleep. It may have potential value in predicting the clinical outcomes of OSA based on its correlation with ESS scores and morning blood pressure as well as its independent association with the prevalence of CVDs, whereas the AHI is not significantly associated with CVD prevalence.

KEYWORDS:

• Apnea/hypopnea index
• blood pressure
• cardiovascular diseases
• hypoxia burden index
• obstructive sleep apnea

Acknowledgments

None reported.

Declaration of interest

All authors certify that they have no affiliations with, or involvement in, any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers’ bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript. PGM peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Previous presentations

2016 Annual Congress of Chinese Thoracic Society (2016.9): Poster

The 8th Annual Conference of CMDA Sleep Medicine (2017.7): Poster

Informed consent

Informed consent was obtained from all individual participants included in the study.

Additional information

Funding

No was received for this research.