多导睡眠监测在肥胖低通气综合征早期识别中的应用

Application of polysomnography in early identification of obesity hypoventilation syndrome

目的探讨多导睡眠监测(PSG)在肥胖合并阻塞性睡眠呼吸暂停(OSA)患者中早期识别肥胖低通气综合征(OHS)的应用价值。方法选择2017年1月—2018年12月在上海交通大学医学院附属第九人民医院行减重代谢手术(MBS)的病态肥胖合并OSA的患者171例,其中男83例、女88例,平均年龄为(32±10)岁,平均BMI为(40.2±7.4)kg/m2。根据有无合并OHS将患者分为OSA组(129例)和OSA+OHS组(42例)。所有患者均于睡眠监测室接受整夜PSG检查和动脉血气分析(ABGA)。记录PSG指标:呼吸紊乱指数(AHI)、氧减指数(ODI)、最长呼吸暂停时间(LAT)、平均血氧饱和度(MSO2)、最低血氧饱和度(NSO2)、血氧饱和度<90%事件占总睡眠时间百分比(SIT90)。检测并记录FBG、HbA1c、TG、HDL-C水平。采用单因素和多因素logistic分析OHS的预测指标。结果OSA+OHS组的年龄、BMI、腰围、颈围均显著大于OSA组(P值分别<0.01或0.05),男性、高血压患者所占比例均显著高于OSA组(P值分别<0.01或0.05)。OSA+OHS组的AHI和ODI均显著大于OSA组(P值均<0.01),LAT显著长于OSA组(P<0.01),MSO2、NSO2、SIT90均显著低于OSA组(P值均<0.01)。单因素logistic回归分析结果显示,肥胖合并OSA患者的年龄(OR=1.039,95%CI为1.005~1.075,P=0.026)、BMI(OR=1.063,95%CI为1.013~1.115,P=0.013)、腰围(OR=1.025,95%CI为1.001~1.049,P=0.038)、AHI(OR=1.034,95%CI=1.021~1.048,P<0.001)、ODI(OR=1.026,95%CI为1.009~1.043,P=0.002)、LAT(OR=1.033,95%CI为1.016~1.049,P<0.001)、MSO2(OR=0.772,95%CI为0.701~0.850,P<0.001)、NSO2(OR=0.930,95%CI为0.904~0.955,P<0.001)、SIT90(OR=1.055,95%CI为1.035~1.075,P<0.001)是OHS发生的预测指标;多因素logistic回归分析结果显示,肥胖合并OSA患者的AHI和MSO2是OHS发生的独立预测指标(P值均<0.05)。新变量Pre-1的ROC AUC为0.824,高于各检验变量单独应用的AUC(P值均<0.05),选择约登(Youden)指数最大的截断点对应的界值(Pre-1=826.7)作为OHS的诊断标准,得出其敏感度和特异度分别为0.733和0.818。结论对于肥胖合并OSA患者,AHI和MSO2是OHS发生的独立预测指标;与PSG相关指标单独应用相比,AHI与MSO2联合应用或许更有助于OHS的早期识别。

Objective To investigate the value of polysomnography(PSG)in early identification of obesity hypoventilation syndrome(OHS)in obese patients with obstructive sleep apnea(OSA).Methods A total of 171 obese patients with OSA who underwent metabolic and bariatric surgery(MBS)in our hospital between January 2017 and December 2018 were included in the present study.There were 83 males and 88 females with an average age of(32±10)years,as well as an average body mass index(BMI)of(40.2±7.4)kg/m2.Of them,129 suffered from OSA only(OSA group)and 42 had both OSA and OHS(OSA+OHS group).All the patients went through standard full-night PSG in the sleep monitoring studio and arterial blood gas analysis(ABGA).Observation indicators of PSG included apnea hypopnea index(AHI),oxygen desaturation index(ODI),longest apnea time(LAT),mean oxygen saturation(MSO2),nadir oxygen saturation(NSO2),and oxygen saturation less than 90%of total sleep time in total sleep time(SIT90).Fasting blood glucose(FBG),glycosylated hemoglobin(HbA1 c),triglyceride(TG),and high-density lipoprotein cholesterol(HDL-C)levels were also recoded.Univariate and multivariate logistic regressions were performed to analyze the predictors of OHS.Results The age,BMI,waist circumference,neck circumference and proportions of male and hypertension in OSA+OHS group were significantly higher than those in OSA group(P<0.01 or 0.05).As for PSG indicators,OSA+OHS patients showed higher AHI,ODI,LAT,and lower MSO2,NSO2 and SIT90 as compared to OSA patients(P<0.01).Univariate analysis showed that age(odds ratio[OR]=1.039,95%CI:1.005-1.075,P=0.026),BMI(OR=1.063,95%CI:1.013-1.115,P=0.013),waist circumference(OR=1.025,95%CI:1.001-1.049,P=0.038),AHI(OR=1.034,95%CI:1.021-1.048,P<0.001),ODI(OR=1.026,95%CI:1.009-1.043,P=0.002),LAT(OR=1.033,95%CI:1.016-1.049,P<0.001),MSO2(OR=0.772,95%CI:0.701-0.850,P<0.001),NSO2(OR=0.930,95%CI:0.904-0.955,P<0.001),and SIT90(OR=1.055,95%CI:1.035-1.075,P<0.001)were predictive indexes of OHS in obese patients with OSA.Multivariate analysis showed that AHI and MSO2 were independent predictors of OHS in obese patients with OSA(both P<0.05).The new variable was defined as Pre-1,whose area under the curve(AUC)in the receiver operating characteristic(ROC)curve was higher than any of AUCs for variables tested separately(AUC=0.824,P<0.05).The sensitivity and specificity of the cutoff point of Pre-1 with the biggest Youden index(Pre-1=826.7)were 0.733 and 0.818 for the OHS diagnosis,respectively.Conclusion AHI and MSO2 are independent predictors of OHS in obese patients with OSA.Compared to PSG-related indicators used separately,the combination of AHI and MSO2 may be more helpful for early identification of OHS.