中高海拔地区阻塞性睡眠呼吸暂停患者的运动能力

文献信息

中文摘要

背景： 目前尚不清楚中高海拔地区阻塞性睡眠呼吸暂停（OSA）患者的运动能力下降程度。
目的： 主要目的是使用心肺运动试验（CPET）比较中高海拔（约1,900米）地区OSA患者与健康对照（HCs）之间的每公斤体重峰值摄氧量（VO2/kg）。次要目的是评估OSA严重程度（呼吸暂停低通气指数，AHI）和夜间低氧血症（最低氧饱和度，LSpO2；氧减指数，ODI）与CPET参数的关联，并探索CPET指标的潜在判别性能。
方法： 这项前瞻性研究招募了来自中国云南省昆明市的38名OSA患者（AHI ≥ 5次/小时）和36名健康对照（研究地点海拔：约1,900米；参与者居住海拔范围：海拔1,800-2,800米）。所有参与者均接受了整夜多导睡眠监测和使用自行车测力计斜坡方案的症状限制性CPET。两组均按呼吸暂停低通气指数（AHI）严重程度和最低氧饱和度（LSpO2）进行亚组分组以进行CPET比较。
结果： 调整BMI后，与健康对照相比，OSA组表现出显著较低的VO2/kg（P = 0.013）和显著较高的VE/VCO2斜率（P = 0.038）。AHI和ODI与VO2/kg呈负相关，LSpO2与VO2/kg呈正相关；LSpO2与VO2/WR呈正相关，但与VE/VCO2斜率呈负相关；ODI与VE/VCO2斜率呈正相关。此外，在一项探索性ROC分析中，VO2/kg显示出中等AUC（0.69）、高敏感性（97.4%）和有限特异性（38.9%），表明其具有支持性而非独立筛查作用。
结论： 中高海拔地区的OSA患者表现出运动能力降低（较低的VO2/kg）和通气效率低下（较高的VE/VCO2斜率），与OSA严重程度和夜间低氧血症相关；调整BMI后，VO2/kg和VE/VCO2斜率差异仍然存在。这些限制可能反映了叠加的慢性间歇性和环境性缺氧，骨骼肌功能障碍、通气控制改变和内皮损伤可能是潜在机制。CPET提供了有价值的功能评估；在一项探索性分析中，CPET参数可作为支持性指标以提高对OSA的怀疑，但不能替代多导睡眠监测。需要在更大规模的多中心队列中进行验证。

英文摘要

BACKGROUND: It remains unknown to what extent exercise capacity is diminished at moderate to high altitudes in patients with obstructive sleep apnea (OSA).
PURPOSE: The primary aim was to compare peak oxygen uptake per kilogram body weight (VO2/kg) between OSA patients and healthy controls (HCs) at moderate-to-high altitude (~ 1,900 m) using cardiopulmonary exercise testing (CPET). Secondary aims were to evaluate the associations of OSA severity (apnea-hypopnea index, AHI) and nocturnal hypoxemia (lowest oxygen saturation, LSpO2; oxygen desaturation index, ODI) with CPET parameters, and to explore the potential discriminatory performance of CPET indices.
METHODS: This prospective study enrolled 38 OSA patients (AHI ≥ 5 events/h) and 36 healthy controls from Kunming, Yunnan Province, China (study site altitude: ~1,900 m; participants' residence altitude range: 1,800-2,800 m above sea level). All participants underwent overnight polysomnography and symptom-limited CPET using a cycle ergometer ramp protocol. Both groups were subgrouped by apnea-hypopnea index (AHI) severity and by lowest oxygen saturation (LSpO2) for CPET comparisons.
RESULTS: After adjustment for BMI, the OSA group exhibited significantly lower VO2/kg (P = 0.013) and a significantly higher VE/VCO2 slope (P = 0.038) compared with healthy controls. AHI and ODI were negatively correlated, and LSpO2 positively correlated, with VO2/kg; LSpO2 was positively correlated with VO2/WR but negatively correlated with VE/VCO2 slope; ODI was positively correlated with VE/VCO2 slope. Additionally, in an exploratory ROC analysis, VO2/kg showed a modest AUC (0.69), high sensitivity (97.4%) and limited specificity (38.9%), suggesting a supportive rather than standalone screening role.
CONCLUSIONS: OSA patients at moderate-to-high altitude show reduced exercise capacity (lower VO2/kg) and ventilatory inefficiency (higher VE/VCO2 slope), correlating with OSA severity and nocturnal hypoxemia; the VO2/kg and VE/VCO2 slope differences persisted after adjustment for BMI. These limitations may reflect superimposed chronic intermittent and environmental hypoxia, with skeletal muscle dysfunction, altered ventilatory control, and endothelial impairment as possible contributing mechanisms. CPET provides valuable functional assessment; in an exploratory analysis, CPET parameters may serve as supportive indicators to raise suspicion for OSA but cannot replace polysomnography. Validation in larger, multi-center cohorts is required.