合并阻塞性睡眠呼吸暂停低通气综合征对慢性阻塞性肺疾病患者心功能的影响

目的分析单纯慢性阻塞性肺疾病(简称慢阻肺)患者与慢阻肺合并阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者的临床特征,研究合并OSAHS对慢阻肺患者心功能的影响。方法本研究回顾性纳入2016年9月至2018年10月就诊于北京大学第三医院呼吸与危重症医学科门诊的稳定期慢阻肺患者126例,其中男112例,女14例,年龄48~89岁,中位年龄67岁。以呼吸暂停低通气指数(AHI)5次/h为界值,分为单纯慢阻肺组(31例)和慢阻肺合并OSAHS组(95例),比较患者的人口学特征、呼吸道症状、肺功能、心血管事件发生率和反映患者的患者心功能的超声心动图E/e′比率、左心房前后径(LAD)及左心室射血分数(LVEF)等指标,采用独立样本t检验、卡方检验等对数据进行统计学分析。结果单纯慢阻肺患者与慢阻肺合并OSAHS患者的人口学特征、呼吸道症状、肺功能差异均无统计学意义,各项夜间血氧饱和度水平指标差异均有统计学意义(均P<0.05),两组患者左心室质量指数(LVMI)差异有统计学意义(P=0.047),而心血管事件发生率差异无统计学意义。AHI≥30次/h的合并严重OSAHS的患者与AHI<30次/h的非严重OSAHS的患者相比,超声心动图指标E/e′(P=0.013)、LAD(P=0.006)、LVMI(P=0.051)、LVEF(P=0.030)差异均有统计学意义,冠心病及充血性心力衰竭病史差异有统计学意义(P=0.025,P<0.001)。按轻中重度对慢阻肺合并OSAHS患者严重程度进行分组后,E/e′及LAD与严重程度明显相关(P=0.045,P=0.011)。夜间血氧饱和度水平方面,夜间平均血氧饱和度和E/e′、LAD、LVMI均有显著相关性(r=-0.195,P=0.033;r=-0.197,P=0.030;r=-0.195,P=0.044);血氧饱和度≤90%的比例与LAD有显著相关性(r=0.209,P=0.021)。多元线性回归模型中,AHI每增加一个单位时E/e′平均增加0.070,氧减指数每增加一个单位时E/e′平均增加0.084。结论慢阻肺合并重度OSAHS的患者与慢阻肺合并非重度OSAHS患者相比,左心舒张功能显著降低且发生充血性心力衰竭和冠心病的风险显著增加,且慢阻肺合并OSAHS的严重程度与左心舒张功能受限的严重程度相关,AHI越高、氧减指数越高,左心舒张功能受限及结构改变越严重。

Effects of obstructive sleep apnea hypopnea syndrome on cardiac function in patients with chronic obstructive pulmonary disease

Objective To analyze the clinical characteristics of patients with chronic obstructive pulmonary disease(COPD)and COPD overlapping obstructive sleep apnea hypopnea syndrome(overlap syndrome),and to study the relationship between overlap syndrome and cardiovascular diseases.Methods A total of 126 stable COPD patients admitted to the Respiratory Department of Peking University Third Hospital from September 2016 to October 2018 were included in this study,including 112 males and 14 females,ranging in age from 48 to 89 years,with a median of 67 years.With apnea hypopnea index(AHI)5 times/h for the cutoff value,we classified the patients into a simple COPD group(31 cases)and an overlap syndrome group(95 cases),and compared the patients′demographic characteristics,respiratory symptoms,lung function,the incidence of cardiovascular events and the cardiac function with echocardiography(E/e′),left atrium diameter(LAD)and left ventricular ejection fraction(LVEF),by using independent-samples T test and chi-square test.Results There were no statistically significant differences in demographic characteristics,respiratory symptoms,pulmonary function,cardiac function between COPD patients and overlap syndrome patients,but significant differences in blood oxygen level at night and left ventricular mass index(LVMI)between these groups(P=0.014,P<0.001,P<0.001,P<0.001,P=0.047,respectively)were observed.By comparing the severe sleep apnea hypopnea syndrome(AHI≥30)with sleep apnea hypopnea syndrome patients(AHI<30),there were statistically significant differences in echocardiographic indicators,among which there were statistically significant differences in E/e′(P=0.013),LAD(P=0.006),LVMI(P=0.051)and LVEF(P=0.030).There were also significant differences in the history of coronary heart disease and congestive heart failure between the two groups(P=0.025,P<0.001).After dividing the patients with overlap syndrome by mild,moderate and severe severity,E/e′and LAD were significantly correlated with severity(P=0.045,P=0.011).In terms of blood oxygen level at night,there was a significant correlation between average blood oxygen saturation at night and E/e′,LAD,and LVMI(r=-0.195,P=0.033;r=-0.197,P=0.030;r=-0.195,P=0.044);moreover,there was also a significant correlation between the ratio of blood oxygen≤90% and LAD(r=0.209,P=0.021).In the multiple linear regression model,E/e′increased by 0.070 on average for each unit increase in AHI,and 0.084 on average for each unit increase in oxygen desaturation index(ODI).Conclusions Patients with COPD overlapping severe sleep apnea hypopnea syndrome showed worse left diastolic function and higher risk of congestive heart failure and coronary heart disease compared with the patients with COPD alone.In addition,the degree of impairment of left heart diastolic function was associated with the severity of COPD overlapping sleep apnea hypopnea syndrome.The higher the AHI and the ODI became,the more severe the left heart diastolic restriction and structures changed.