ABSTRACT
Objective:To investigate the prevalence of abnormal lung ventilation function in asymptomatic subjects receiving healthy examination and the risk factors of small airway dysfunction (SAD).Methods:From August 2016 to October 2017, the pulmonary function test results of 610 healthy subjects who met the standards of this study in Fuxing Hospital affiliated to Capital Medical University were analyzed. The detection rate of abnormal lung function was described; the difference of lung function was compared between smokers and non-smokers, among groups with different smoking age, between individuals with normal body mass index and obese individuals; the risk factors of SAD was investigated; and the characteristics of abnormal lung function in asymptomatic subjects receiving physical examinations were summarized.Results:Among the 610 subjects, the overall prevalence of abnormal pulmonary function was 42.6%, and the rate of obstructive, restrictive, mixed and pure SAD were 16.7% and 5.9%, 2.5% and 17.5% respectively. The prevalence of the ratio of forced expiratory volume in 1 second (FEV 1) to forced vital capacity (FVC) (FEV 1/FVC) less than 70% was 4.6%; small airway function indicators of maximal mid expiratory flow (MMEF), forced expiratory flow at 50% and 75% of forced vital capacity (FEF 50% and FEF 75%) for smokers were significantly lower than that of non-smokers, and decreased progressively with smoking age. Smoking was an independent risk factor for SAD. Compared with non-smokers, smokers had a 65-fold increase in the risk of SAD. Obesity was not associated with SAD. Conclusions:The prevalence of abnormal lung function is high in asymptomatic subjects receiving healthy examination. The main abnormalities are obstructive ventilation dysfunction and SAD. Cigarette smoking is the major risk factor for SAD.
ABSTRACT
Objective:To analyze the pulmonary function after pneumonia in children over 3 years old.Methods:This was an observational study recruiting children discharged from Beijing Children′s Hospital, Capital Medical University between January 1, 2016 and December 31, 2017 with the first diagnosis of pneumonia who were re-examined for pulmonary function within 0.5 to 2.0 years follow-up at outpatient department.Medical records during hospitalization, clinical information, pulmonary function and/or chest imaging examination were collected for analyzing lung function and relevant risk factors.Results:A total of 159 eligible patients who were followed up at the outpatient department were recruited, involving 100 patients receiving the lung function examination, and among them, 46 had abnormal lung function.There was no significant correlation between the gender and the pulmonary function after pneumonia ( χ2= 0.975, P=0.323). No correlation was found between the pulmonary function and pneumonia pathogens ( χ2=0.549, P=0.908). Children with severe pneumonia ( χ2=5.154, P=0.023) and abnormal chest imaging after pneumonia ( χ2=4.464, P=0.035) were more likely to have lung dysfunction.Among 74 children over 6 years old, there were 45 cases(60.81%) had pulmonary dysfunction after pneumonia, manifesting as the reduced forced expiration volume in one second (FEV 1), forced vital capacity (FVC), forced expiratory flow at 50% vital capacity, forced expiratory flow at 75% vital capacity, maximum mid-expiratory flow and FEV 1/FVC%. Conclusions:Lung dysfunction may occur after pneumonia, manifesting as small airway dysfunction, obstructive ventilation dysfunction and mixed ventilation dysfunction.The gender and etiology of pneumonia are not correlated with lung dysfunction after pneumonia.Children with severe pneumonia and continuous imaging abnormalities are more likely to have lung dysfunction.