老年人小气道功能障碍对肺弥散功能影响的临床研究

Effect of small airway dysfunction on pulmonary diffusion function in the elderly

目的探讨老年人小气道功能障碍对肺弥散功能的影响。方法选取2016年1月至2021年6月在温州市中心医院健康体检中心、门诊和住院且完成全套肺功能检测的老年人122例,其中单纯小气道功能障碍62例(观察组),肺功能正常60例(对照组)。分析两组肺弥散功能指标与小气道功能指标的相关性,并比较两组患者肺弥散功能的差异。结果两组一氧化碳弥散量(D_(L)CO)与呼出50%肺活量时的瞬间流速(MEF50)、呼出75%肺活量时的瞬间流速(MEF25)和最大呼气中段流速(MMEF)分别均呈正相关(r=0.323~0.599,均P<0.05),两组弥散比(KCO)与MEF50、MEF25和MMEF均无相关性(均P>0.05);观察组患者D_(L)CO、KCO均明显低于对照组(均P<0.01);观察组中重度患者D_(L)CO低于轻度患者(P<0.01),但KCO比较差异无统计学意义(P>0.05);观察组患者D_(L)CO和KCO异常率均高于对照组,差异均有统计学意义(均P<0.01)。结论老年人单纯小气道功能障碍对肺弥散功能有着一定程度影响并存在相关关系,建议对同时存在已知非职业因素引起小气道功能障碍的职业病患者进行肺功能损伤评定时,D_(L)CO指标采用相应公式矫正后再判读以减少假阳性。

Objective To investigate the effect of small airway dysfunction on pulmonary diffusion function in the elderly.Methods A total of 122 elderly subjects who underwent health check-up in Wenzhou Central Hospital from January 2016 to June 2021 were enrolled in the study,including 62 subjects with simple small airway dysfunction(study group)and 60 subjects with normal lung function(control group).The correlation between lung diffusion function index and small airway function index was analyzed.Results The diffusion capacity of the lung for carbon monoxide(D_(L)CO)was positively correlated with maximal expiratory flow when 50%of the FVC has been expired(MEF50),maximal expiratory flow when 75%of the FVC has been expired(MEF25)and maximum mid-expiratory flow(MMEF),respectively(r=0.323-0.599,all P<0.05),while the specific diffusing capacity(KCO)was not correlated with MEF50,MEF25 or MMEF in two groups(all P>0.05).The D_(L)CO,KCO indexes in the study group were significantly lower than those in the control group(both P<0.01).There was a significant difference between the mild and medium/severe D_(L)CO in the study group(P<0.01),but there was no difference in KCO(P>0.05).The abnormal positive rates of D_(L)CO and KCO in the study group were higher than those in the control group(both P<0.01).Conclusion Simple small airway dysfunction in the elderly has a certain degree of influence on lung diffusion function and there is a correlation.For lung impairment assessment in patients with small airway dysfunction caused by non-occupational factors,it is recommended that the D_(L)CO judgment standard should adopt the corresponding correction formula to reduce the false positives.