OBJECTIVETo establish predictive equations of lung function for adults in urban areas in north China.

METHODSA survey was conducted in 600 male and 600 female healthy adults in the urban areas in north China. Five flow-volume test parameters were measured including forced vital capacity (FVC) and forced expiratory volume in one second (FEV1). Stepwise multiple regression was carried out to establish the predicative equations for the parameters for male and female adults separately. The predicted values from these equations and those from other commonly used equations (such as ECCS equation and Knudson equation) were compared with the actual measurements in pulmonary function tests.

RESULTSFour flow-volume test parameters, namely FVC, FEV1, 25% forced expiratory flow (FEF25%), and FEF75%, showed obvious differences between the male and female adults, while FEV1/FVC was not correlated with gender. Multiple regression analysis showed that FVC, FEV1, FEF25% and FEF75% were positively correlated with height and negatively with age, and FEV1/FVC was negatively correlated with both height and age. The parameters were not affected by body weight. The predicted values from our equations were closer to the actual measurements than those calculated from other equations.

CONCLUSIONThe equations we established are more appropriate than the generally used equations for predicting lung functions in adults in north China urban areas.

Adult ; Age Factors ; Body Height ; Body Weight ; China ; Female ; Forced Expiratory Volume ; Humans ; Lung ; physiology ; Male ; Middle Aged ; Predictive Value of Tests ; Reference Values ; Regression Analysis ; Respiratory Function Tests ; methods ; Sex Factors ; Spirometry ; statistics & numerical data ; Urban Population ; Vital Capacity

UNLABELLEDMorbidity of chronic lung disease in young children is relatively high, and could increase in the future. Pulmonary function testing is used for clinical assessment of patients with suspected or obvious pulmonary disease to assess the severity of dysfunction and to evaluate therapeutic effectiveness. In the recent few years, forced expiratory parameters assessing lung function have been measured in older children. In order to assess abnormalities of lung function in preschool patients with respiratory disorders based on changes of forced expiratory parameters, adequate reference values are needed. However, such data in healthy preschool children remain scant in the literature.

OBJECTIVEThe aim of this study was to characterize the spirometry of preschool children and establish the normal lung function prediction equations for Chinese preschool children.

METHODSA survey in 343 healthy preschool children (184 boys and 159 girls) aged 3 to 6 years (73 children aged 3 years, 96 children aged 4 years, 91 children aged 5 years and 83 children aged 6 years) was carried out in Shenzhen in 2004. Eleven flow volume tests parameters, i.e., forced vital capacity (FVC), forced expiratory volume at 0.5 second (FEV(0.5)), forced expiratory volume at 0.75 second (FEV(0.75)), forced expiratory volume at one second (FEV(1)), maximal mid expiratory flow rate (FEF(25%-75%)), peak expiratory flow (PEF), forced expiratory time (FET100%) were measured by using COSMED spirometry produced in Italy. Stepwise multiple regressions and non-linear regressions were carried out with the statistical software SPSS10.0 for Windows to identify the best predictors of lung function parameters using standing height, weight, age and gender as potential determinants.

RESULTSSpirometric tests could be successfully carried out by using imagery methods in the following percentages of children: 69.9% of 3 to 4 years old, 70.8% of 4 to 5 years old, 92.3% of 5 to 6 years old and 91.6% of 6 to 7 years old children, 77.7% of the selected population (217/279) of children performed at least two acceptable tests respectively. The average forced expiratory time (FET) was 1.61 +/- 0.52 sec (x +/- s), the 5th percentile value was 0.9 sec, 18 of 279 (6.5%) children produced a FET less than 1 second. Forced expiratory volume in 0.50 and 0.75 sec (FEV(0.5), FEV(0.75)) were thus measured necessary in preschool children. All lung volumes and flow rates increased with age, height as well as weight growth in both gender groups. The correlation among most lung function parameters was higher in height than in age and weight in boys. Whereas the correlation among most lung function parameters was higher in age than in height and weight in girls. The regression equations of lung function were established. By comparison with the equations derived from this study and from studies by Nystad, it was found that there was a difference between the predicted values.

CONCLUSIONSpirometric testing is feasible in preschool children by using imagery methods and may be useful for both clinical practice and research. The correlation among most lung function parameters was higher in height than in age and weight in boys. Whereas the correlation among most lung function parameters was higher in age than in height and weight in girls.

Age Factors ; Body Height ; Body Weight ; Child ; Child, Preschool ; Feasibility Studies ; Female ; Forced Expiratory Volume ; Humans ; Male ; Peak Expiratory Flow Rate ; Reference Values ; Regression Analysis ; Respiratory Function Tests ; methods ; Spirometry ; statistics & numerical data ; Vital Capacity

BACKGROUND: Time to first cigarette after waking is an indicator of nicotine dependence. We aimed to identify the association between time to first cigarette and spirometry-proven obstructive respiratory impairment, especially chronic obstructive pulmonary disease, in current smokers. METHODS: We included 392 subjects who visited the comprehensive medical examination center of Hallym University Sacred Heart Hospital between July 2014 and September 2015. Subjects with lung disease or anemia were excluded. Obstructive pulmonary impairment was defined as < 70% of the predicted value of forced expiratory volume in 1 second/forced vital capacity. Subjects were classified into the early (≤30 minutes) and late (>30 minutes) groups based on the time to first cigarette. Logistic regression and linear regression analyses were used for data analysis. RESULTS: Ninety-eight subjects (25%) were classified into the early group. After adjusting for smoking behaviors (cigarettes per day and smoking duration), socioeconomic status (education and income), age, and physical activity, an early time to first cigarette was found to be associated with an increased risk of obstructive pulmonary impairment measured using spirometry (adjusted odds ratio, 2.84; 95% confidence interval, 1.22–6.61). CONCLUSION: Compared to current smokers with a late time to first cigarette, those with an early time to first cigarette had a higher risk of obstructive pulmonary impairment, especially chronic obstructive pulmonary disease. Classifying smoking-related behaviors, especially time to first cigarette, may help target clinical screening for chronic obstructive pulmonary disease.
Anemia ; Forced Expiratory Volume ; Heart ; Linear Models ; Logistic Models ; Lung Diseases ; Mass Screening ; Motor Activity ; Odds Ratio ; Pulmonary Disease, Chronic Obstructive* ; Respiratory Function Tests ; Smoke ; Smoking ; Social Class ; Spirometry* ; Statistics as Topic ; Tobacco Products* ; Tobacco Use Disorder ; Vital Capacity

The first national surveillance of COPD in mainland China was carried out in 2014, with the nationally representative data obtained. The national surveillance was significantly important for the monitoring of prevalence, risk factors, and changing trend of COPD among Chinese adults aged ≥ 40. The surveillance was also important in the development of national COPD prevention and control policy, the evaluation of prevention and control progress, the establishment of COPD comprehensive surveillance system, and the building of a professional COPD monitoring and prevention team. In this editorial, we briefly introduced the method and content of COPD surveillance, and reported the rate of spirometry examination and COPD awareness among adults aged ≥40 in China. We also analyzed the rate of main risk factors for COPD, such as tobacco smoking, occupational exposure to dust or chemical and indoor exposure to biomass or coal, and the distribution of high-risk population. This study provided fundamental data for the prevention and control of COPD in China.
Adult ; Aged ; Air Pollution, Indoor/statistics & numerical data* ; China/epidemiology* ; Chronic Disease/epidemiology* ; Dust ; Female ; Humans ; Male ; Occupational Exposure/statistics & numerical data* ; Population Surveillance/methods* ; Prevalence ; Pulmonary Disease, Chronic Obstructive/prevention & control* ; Risk Factors ; Smoking ; Spirometry ; Tobacco Smoke Pollution/statistics & numerical data*

The aim of the study was to evaluate the prevalence of restrictive ventilatory defect and to determine the risk factors in subjects with spirometrically-defined restrictive ventilatory defect. We used the population-based, fourth-2, 3 (2008, 2009) and fifth (2010-2012) Korea National Health and Nutrition Examination Survey (KNHANES) to analyze 15,073 subjects, aged > or =40 yr who underwent spirometry. Chest radiographs were also analyzed to identify restrictive lung disease. Spirometrically-defined restrictive ventilatory defect (FEV1/FVC> or =70% and FVC<80% of mean predicted value) was detected in 11.3% (n= 1,709) of subjects aged > or =40 yr. The prevalence increased to 12.3% on using the lower limit of normal (LLN) criteria. Approximately 99.4% of subjects were classified as mild restrictive. Among these, 11.3% had inactive tuberculosis (TB) lesion, 2.2% cardiac disease, 2.0% previous operation scar or radiation injury and/or mediastinal disease, and 7.4% other pulmonary disease suggestive of restrictive lung diseases on chest radiograph. Evidence of previous TB history was independently associated with restrictive ventilatory defect (odds ratios [OR], 1.78; 95% confidence interval, 1.45-2.18) after adjustment for gender, age, smoking, area for residence and body mass index. The prevalence of restrictive ventilatory defect among the nationwide population in Korea was 11.3% with fixed ratio criterion and 12.3% with LLN criterion. Most cases were of the mild restrictive category and previous TB history is the independent risk factor for restrictive ventilatory defect.
Adult ; Age Distribution ; Aged ; Aged, 80 and over ; Educational Status ; Female ; Health Care Surveys ; Housing ; Humans ; Income ; Lung Diseases, Obstructive/*diagnosis/*epidemiology ; Male ; Middle Aged ; Prevalence ; Reproducibility of Results ; Republic of Korea/epidemiology ; Risk Factors ; Sensitivity and Specificity ; Sex Distribution ; Smoking/*epidemiology ; Spirometry/*statistics & numerical data