| A Physiologically High-Risk Subgroup Within Moderate Obstructive Sleep Apnea |
Jong Kwan Kim
, Myoung Su Choi
|
| Department of Otolaryngology-Head and Neck Surgery, Daejeon Eulji Medical Center, Eulji University, Daejeon, Korea |
| 높은 저산소 부담을 동반한 중등도 폐쇄성 수면무호흡증 |
| 김종관
, 최명수
|
| 을지대학교 의과대학 대전을지대학교병원 이비인후과학교실 |
|
|
|
Received: 1 April 2026; Revised: June 12, 2026 Accepted: 22 June 2026. Published online: 4 August 2026. |
|
|
|
| ABSTRACT |
Background and Objectives
While the apnea-hypopnea index (AHI) is the standard for obstructive sleep apnea (OSA) classification, it only measures event frequency. It fails to account for the duration and depth of desaturation. In contrast, hypoxic burden (HB) addresses this by integrating the area under the nocturnal desaturation curve. This study aimed to characterize patients with moderate AHI who exhibit a disproportionately high HB.
Subjects and Method
This retrospective study analyzed overnight polysomnography data from 319 adults (AHI ≥15 events/h). HB was estimated using an approximated formula (approximated HB, aHB). Patients with moderate OSA were stratified into a moderate-low (ML; aHB <60 %·min/h, n=111) group and a moderate-high (MH; aHB ≥60 %·min/h, n=14) group. A severe subgroup (SS; AHI 30.0-47.7/h, n=98), comprising the lower 50th percentile of severe OSA patients by AHI, served as the comparison group.
Results
Despite similar AHI levels, MH and ML exhibited markedly different aHB (MH 70.3±7.4 %·min/h vs. ML 26.3±12.9 %·min/h; p<0.001). Critically, the aHB of MH was statistically equivalent to that of SS (p=0.401). After adjusting for AHI, age, and body mass index in multivariable regression, neck circumference was not a significant predictor of aHB (β=-0.071, p=0.936).
Conclusion
A subtype of moderate OSA patients with high aHB (≥60 %·min/h) exhibits a nocturnal desaturation profile statistically equivalent to that of early severe OSA, characterized by prolonged apneic events and greater desaturation depth. |
| Keywords:
Apnea-hypopnea indexㆍ Hypoxic burdenㆍ Obstructive sleep apneaㆍ Polysomnography |
|
PDF Links
Full text via DOI
Download Citation 
