U-shaped association between hematocrit and resting pulse oxygen saturation in Tibetan plateau population

ObjectiveTo investigate the relationship between hematocrit (HCT) and low resting oxygen saturation in Tibetan plateau population.MethodsThis retrospec-tive cohort study included 3075 Tibetan adult inpatients who underwent elective non-cardiac, non-thoracic surgery at Tibet Autonomous Region People’s Hospital between January 2023 and October 2024. Multivariate logistic regression was used to assess the association between HCT and low resting oxygen saturation (SpO2ResultsMultivariate logistic regression analysis showed that elevated HCT was an independent risk factor for low oxygen saturation in the patients. For every 5-percentage-point increase in HCT, the risk of low oxygen saturation increased by 12% (PPPPConclusionsThere is a U-shaped association between HCT and low resting oxygen saturation in the Tibetan plateau population. An HCT level exceeding the population-specific threshold suggests that the adaptive erythropoietic response to high-altitude hypoxia may transition from being compensatory to potentially detrimental.