Analysis Of Clinical Characteristics Of Obstructive Sleep Apnea Syndrome Complicated With Chronic Obstructive Pulmonary Disease

Objective:To study the clinical characteristics and influencing factors of obstructive sleep apnea hypopnea syndrome（OSAHS）complicated with chronic obstructive pulmonary disease（COPD）,namely COPD-OSAHS overlap syndrome,so as to provide understanding and guidance for clinical practice.Methods:A retrospective case-control study was conducted on 301 patients with OSAHS admitted to the second affiliated Hospital of Kunming Medical University from March 2015 to June 2022.According to the pulmonary function test,the patients were divided into two groups:simple obstructive sleep apnea hypopnea syndrome group（n=146 cases）and COPD-OSAHS overlap syndrome group（n=155 cases）,The COPD-OSAHS overlap syndrome group was divided into mild group（GOLD1grade）,moderate group（GOLD2 grade）and severe and very severe group（GOLD3/4grade）based on GOLD grade.And the COPD-OSAHS overlap syndrome group was divided into two groups:COPD patients with the emphysematous phenotype and non-emphysematous phenotype according to Goddard’s classification criteria.The demographic data[age,sex,smoking,length of hospital stay,body mass index（BMI）],cardiopulmonary function(pulmonary artery pressure,N terminal pro B type natriuretic peptide（NT-pro BNP）,forced expiratory volume in one second accounts for the percentage of forced vital capacity（FEV₁/FVC）,percentage of predict forced expiratory volume in one second（FEV₁%pred）,diurnal lowest saturation of pulse oxygen（DL-SpO₂）,night polysomnography monitoring indexes[night lowest saturation of pulse oxygen（NL-SpO₂）,night medial saturation of pulse oxygen（NM-SpO₂）,saturation of pulse oxygen less than 85%of the time(TS₈₅),apnea hypopnea index（AHI）,oxygen desaturation index（ODI）,maximum apnea time（ATmax）,maximum hypopnea time（HTmax）],inflammatory factor indicators[neutrophil to lymphocyte ratio（NLR）,procalcitonin（PCT）,interleukin-6（IL-6）,hypersensitive C-reactive protein（hs-CRP）],arterial blood gas analysis[potential of hydrogen（p H）,arterial partial pressure of oxygen（Pa O₂）,Arterial Partial Pressure Of Carbon Dioxide（Pa CO₂）,lactic acid（Lac）],chest imaging parameters[infiltrated total volume accounts for total lung volume（infiltrated%）,collapsed total volume accounts for total lung volume（Collapsed%）,percentage of low attenuation area of both lungs lower than-950HU to volume of both lungs（LAA%）],complications（pulmonary heart disease,atrial fibrillation,lower limb edema）,and other characteristics were compared separately.Partial correlation analysis and Logistic regression were used to analyze the influencing factors of OSAHS with COPD.Results:1.A total of 301 patients were included,146 patients classified as the OSAHS group alone,including 102 males（69.90%）,and the age was（52.42±11.97）years;another 155 cases as COPD-OSAHS overlap syndrome group,including 127 cases in male（81.9%）,and the age was（67.18±9.99）years.There were 45 cases,65 cases and 45 cases in OSAHS group with mild,moderate and severe COPD among COPD-OSAHS overlap syndrome group;and 50 cases classified as OSAHS and COPD patients with the emphysematous phenotype group,and another 105 cases as OSAHS and COPD patients with the non-emphysematous phenotype.2.Compared with OSAHS alone,the total COPD-OSAHS overlap syndrome group was more male,older,and had longer hospital stay.There were significant differences in cardiopulmonary function indexes（pulmonary artery pressure,NT-pro BNP,FEV₁/FVC,FEV₁%pred）,hypoxia indexes(DL-SpO₂,NL-SpO₂,NM-SpO₂,TS₈₅,Pa O₂),Pa CO₂,inflammatory factor indicators（IL-6,NLR,hs-CRP）,pulmonary infiltration and exudation（Infiltrated%,Collapsed%）and upper respiratory symptoms（cough,expectoration,dyspnea）.Among the complications,the incidence of pulmonary heart disease,lower limb edema and atrial fibrillation was higher（all P<0.05）.3.There were statistically significant differences in length of hospital stay,cardiopulmonary function indexes,hypoxia indexes,partial inflammatory factors indexes and Pa CO₂in the severe and very severe COPD-OSAHS overlap syndrome group compared with the mild group,and the incidence of pulmonary heart disease was higher（all P<0.05）.And NLR,NL-SpO₂,NM-SpO₂,TS₈₅and PaCO₂were statistically significant differences in different degrees of COPD-OSAHS overlap syndrome group（all P<0.05）.In the partial correlation analysis,FEV₁%pred was negatively correlated with pulmonary artery pressure,NT-pro BNP,TS₈₅,IL-6,hs-CRP,NLR,Pa CO₂and Lac in patients with OSAHS complicated with different severity of COPD（r=0.429,0.281,0.151,0.491,0.400,0.258）,but positively correlated with DL-SpO₂,NL-SpO₂,NM-SpO₂（r=0.417,0.370,0.309）（all P<0.05）.In the Logistic regression analysis of the related factors of OSAHS patients complicated with severe COPD patients,NLR（OR 1.551,95%CI 1.273,1.889）and TS₈₅（OR1.011,95%CI 1.003,1.020）were the main risk factors,and DL-SpO₂was the main protective factor（OR 0.904,95%CI 0.850,0.962）（all P<0.05）.4.There were statistically significant differences in sex,smoking,dyspnea,BMI,AHI,Infiltrated%and Collapsed%in the COPD-OSAHS overlap syndrome with emphysematous phenotype patients compared with the simple OSAHS group and non-emphysematous phenotype group（all P<0.05）.And pulmonary artery pressure,TS₈₅and ODI between COPD-OSAHS overlap syndrome patients with emphysematous phenotype and non-emphysematous phenotype were significant differences（all P<0.05）.The incidence of pulmonary heart disease,atrial fibrillation and lower limb edema was higher in COPD-OSAHS overlap syndrome patients with non-emphysematous phenotype group.The results of correlation analysis showed that BMI,smoking index,AHI,TS₈₅,ODI,Infiltrated%,Collapsed%were negatively correlated with LAA%（r=-0.434,0.254,0.339,0.327,0.336,0.756,0.609）（all P<0.05）.In the Logistic regression analysis of the related factors of COPD patients with emphysematous phenotype and OSAHS patients,BMI（OR 0.891,95%CI 0.807,0.984）,AHI（OR 0.948,95%CI 0.918,0.979）,Collapsed%（OR 0.406,95%CI 0.265,0.623）were the main influencing factors（all P<0.05）.Conclusions:1.In terms of cardiopulmonary function,compared with simple OSAHS patients,COPD-OSAHS overlap syndrome patients have a larger proportion of males,older age,longer hospitalization days,more serious burden of cardiopulmonary function,and higher incidence of pulmonary heart disease,lower limb edema and atrial fibrillation.Compared with mild COPD-OSAHS overlap syndrome group,moderate and severe group have worse cardiopulmonary function.2.In terms of serum inflammatory factors,the inflammatory burden of patients with COPD-OSAHS overlap syndrome was heavier than that of patients with simple OSAHS,in which the IL-6 of severe and very severe COPD-OSAHS overlap syndrome group was higher than that of mild group,and the increase of NLR was more obvious with the deterioration of lung function.NLR is the main influencing factor of OSAHS patients with severe and very severe COPD.3.In terms of hypoxia burden,patients with COPD-OSAHS overlap syndrome has more severe hypoxia and more obvious hypercapnia than patients with simple OSAHS.Compared with mild to moderate COPD-OSAHS overlap syndrome group,patients with moderate and severe COPD-OSAHS overlap syndrome has more obvious hypercapnia and lower Pa O₂than patients with mild COPD-OSAHS overlap syndrome,patients with severe and very severe COPD-OSAHS overlap syndrome had lower DL-SpO₂,NLSpO₂,NM-SpO₂and longer TS₈₅time.TS₈₅and DL-SpO₂were the main influencing factors of patients with OSAHS complicated with severe and very severe COPD.4.Compared with the simple OSAHS group and non-emphysematous phenotype group,COPD-OSAHS overlap syndrome with emphysematous phenotype patients have a larger proportion of males,more smoking,more dyspnea,lower index of BMI and AHI,less collapse%in both lungs.And BMI,AHI and Collapsed%are the main influencing factors in patients with COPD patients with the emphysematous phenotype and OSAHS.