AP-HP, Groupe Hospitalier Universitaire APHP-Sorbonne Université, site Pitié-Salpêtrière, Service de Pathologies Du Sommeil (Département R3S), F-75013 Paris, France; Istituto Auxologico Italiano IRCCS San Luca Hospital, Sleep Disorders Center & Department of Cardiovascular, Neural and Metabolic Sciences, Milan, Italy; University of Milano-Bicocca, Milan, Italy.
APHP, Groupe Hospitalier Pitié-Salpêtrière, Service de Nutrition, Sorbonne Université, Paris, France; Nutriomics, INSERM, Sorbonne Université, Paris, France.
Sleep Med. 2021 Jun;82:18-22. doi: 10.1016/j.sleep.2021.03.024. Epub 2021 Mar 29.
Sleep apnea test (SAT) is a cost-effective approach to evaluate subjects without associated comorbidities suspected for obstructive sleep apnea (OSA), a disorder particularly common in obese subjects. The association of obesity with awake hypercapnia (carbon dioxide arterial pressure, PaCO ≥45 mmHg) defines the obesity-hypoventilation syndrome (OHS), which in turn results in increased morbidity and mortality compared to simple OSA. Isolated hypoventilation during sleep in obese patients (obesity-related sleep hypoventilation, ORSH) is now considered as an early stage of OHS. The aim of this study was to assess the performance of SAT in diagnosing OSA and predicting the presence of ORHS among patients with grade III obesity without awake hypercapnia.
Over a 14-months period, patients with grade III obesity (body mass index≥40 kg/m) presenting moderate-to-severe OSA (apnea-hypopnea index [AHI]≥15) upon SAT and normal awake PaCO at arterial blood gas analysis, systematically underwent in-lab nocturnal polysomnography combined with transcutaneous carbon dioxide pressure (PtcCO) monitoring.
Among 48 patients included in the study, 16 (33%) presented an AHI<15 upon polysomnography and 14 (29%) had ORSH. The test revealed no difference in ORSH prevalence between patients with AHI <15 or ≥15 (31% vs. 25%). No SAT variables were independently associated with increased PtCO.
This study shows that SAT overestimates OSA severity and ORSH affects one third of patients with grade III obesity without awake hypercapnia and with moderate-to-severe OSA at SAT, suggesting how polysomnography combined with PtCO monitoring is the most appropriate diagnostic approach for OSA and ORSH in this population.
评估睡眠呼吸暂停试验（SAT）在诊断阻塞性睡眠呼吸暂停（OSA）和预测无觉醒性高碳酸血症的 III 级肥胖患者中存在肥胖相关睡眠低通气（ORSH）中的作用。
在 14 个月的时间内，对接受 SAT 检查且存在中重度 OSA（呼吸暂停-低通气指数[AHI]≥15）但动脉血气分析中清醒时 PaCO 正常的 III 级肥胖（体重指数≥40 kg/m）患者，系统进行实验室夜间多导睡眠图检查，同时监测经皮二氧化碳分压（PtcCO）。
在纳入研究的 48 例患者中，16 例（33%）在多导睡眠图上 AHI<15，14 例（29%）存在 ORSH。多导睡眠图显示，AHI<15 或 AHI≥15 的患者中 ORSH 的患病率无差异（31% vs. 25%）。没有 SAT 变量与 PtCO 升高独立相关。
本研究表明，SAT 高估了 OSA 的严重程度，ORSH 影响了 1/3 的无觉醒性高碳酸血症的 III 级肥胖且 SAT 时存在中重度 OSA 的患者，这提示多导睡眠图结合 PtcCO 监测是该人群中 OSA 和 ORSH 的最佳诊断方法。
