AUTHOR=Zhou Xiaobo , Gao Simin , Zeng Ping , Li Lin 
  
TITLE=The dose-effect and clinical prediction of the longest apnea duration driving the decrease of blood oxygen: a large sample OSA study with 34-second and 52-second cut-off values was established
  
JOURNAL=Frontiers in Physiology
  
VOLUME=Volume 16 - 2025
  
YEAR=2026
  
URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2025.1691994
  
DOI=10.3389/fphys.2025.1691994
  
ISSN=1664-042X
  
ABSTRACT=ObjectiveTo quantify the relationship between the longest apnea duration (LAD) and the lowest oxygen saturation (LSaO2) in patients with obstructive sleep apnea (OSA) and to develop a predictive model for the risk of LSaO2 decline.MethodsA total of 1716 OSA patients were enrolled and grouped by severity (236 non-OSA, 395 mild, 365 moderate, and 720 severe). Multiple linear regression was used to analyze the dose-effect relationship between LAD and LSaO2. A logistic regression model was developed to predict LSaO2 grade, with the dataset partitioned into a training set (n = 1,372) and a testing set (n = 344) using random sampling.Results(1) For every 1-s increase in LAD, LSaO2 decreased by 0.280% (95% CI: −0.291%∼-0.269%) in a univariate model and still decreased by 0.183% (95% CI: −0.197%∼-0.170%) after adjusting for sex, age, BMI, and AHI; (2) Critical points were identified: LSaO2 was 85% when LAD was 34.20 s and 80% when LAD was 52.07 s; (3) The predictive model showed excellent identification performance for severe (AUC = 0.93) and moderate-severe LSaO2 (AUC = 0.96).ConclusionThe study first quantifies the dose-response relationship between LAD and LSaO2 and establishes relevant clinical thresholds. The developed model can accurately identify patients at risk of severe and moderate-severe hypoxia, offering a new tool for individualized intervention.