Abstract: Objective: Pulmonary function testing (PFT) and electrocardiograph (ECG) are the vital components of the cardiopulmonary exercise test (CPET). This study is to investigate clinical characteristics of abnormal PFT as pulmonary ventilation dysfunction, small airway dysfunction and gas exchange (diffusion) dysfunction. Methods: Across-sectional study was conducted The 76 698 outpatient subjects who received health examination from December 2016 to February 2019 in Henan Provincial People's Hospital were recruited. The results of the ECG, PFT were compared among different sex and age sub-groups. Then the severity of their impaired PFT were analyzed. Results: Among 76 698 subjects, 39 237 subjects were male and 37 461 subjects were female. There were total 71.04% patients with abnormal ECG. There were total 28 273 (36.86%) patients with abnormal pulmonary ventilation function. The 17 570 patients (44.78%) (17 570/39 237) were male, 10 703 patients (28.57%) (10 703/37 461) were female, both the number and percentage of abnormal pulmonary ventilation function in male was significantly more than these in female (P<0.01). The percentage detectable rates of male were significant higher than that of female in all the different age sub-groups: 20~29, 30~39, 40~49, 50~59, 60~69 and ≥70 year (P<0.01). The total detectable abnormal rate of small airway dysfunction were 43 160 and 56.26% (43 160/76 698). The 57.73% (22 661/39 237) in male was significantly higher than 54.72% (20 499/37 461) in female (x²=74.87, P<0.01). The detectable abnormal rate of small airway dysfunction in male were lower than female in 30~39 year and 40~49year sub-groups (P<0.05), but were significantly higher in 20~29, 50~59, 60~69, and ≥70 yr sub-groups (P<0.05). Abnormal gas exchange (diffusion) dysfunction were detected in 28.54% (12 940/45 107) subjects. They were 7 433 (30.55%) in male,and 5 507 (26.50%)in female with significant gender difference (P<0.05). The abnormal diffusion detectable rate in 30~39 year sub-group was significant higher in female than in male (P<0.05), and were slightly higher without significant difference in 20~29 and 40~49 year sub-groups (P>0.05), but were significant lower in female than male in 50~59, 60~69 and ≥70 year sub-groups (P<0.05). Conclusion: The abnormal detectable rates in ECG, pulmonary ventilation dysfunction, gas exchange dysfunction and small airway dysfunction were higher in male than female, and higher in elder ≥70 year subgroup than all other younger age subgroups.

Key words: pulmoonary ventilation functiion, electrocardiogram, epidemiological studies, ventilation function, reduced small airway function