After removing participants with unqualified pulmonary function tests, 66,752 participants were included for analysis. The numbers of participants in the East, Central, and West were 23,703, 19,721, and 23,328, respectively. Participants aged 50–69 years accounted for the greatest proportion in the East, while participants aged 40–49 years accounted for the greatest proportion in the Central and West. There were more female participants in the East and Central, and more male participants in the West (Table 1).
Item East (23,703) Central (19,721) West (23,328) Case/Total Prevalence (%) Case/Total Prevalence (%) Case/Total Prevalence (%) Men 40–49 yr 47/3,079 8.6 264/3,126 7.7 403/4,196 11.1 50–59 yr 679/3,804 17.5 452/3,023 15.3 663/3,646 21.5 60–69 yr 967/3,314 28.8 708/2,756 27.3 963/2,975 36.3 ≥70 yr 511/1,225 44.5 319/938 33.1 459/1,055 49.0 Women 40–49 yr 120/3,547 3.8 97/3,498 3.2 184/4,174 5.2 50–59 yr 284/4,347 7.8 187/3,380 5.9 277/3,934 8.9 60–69 yr 386/3,364 12.2 188/2,321 8.4 327/2,591 14.7 ≥70 yr 218/1,023 21.5 78/679 9.7 153/757 24.7 * East: Beijing, Tianjin, Hebei, Shanghai, Jiangsu, Zhejiang, Fujian; Liaoning; Shandong; Guangdong; Hainan. Central: Shanxi, Anhui, Jiangxi, Heilongjiang, Jilin, Henan, Hubei, Hunan. West: Inner Mongolia; Guangxi; Chongqing; Sichuan; Guizhou; Yunnan; Tibet; Shaanxi; Gansu; Qinghai; Ningxia; Xinjiang.
Table 1. Chronic obstructive pulmonary disease (COPD) prevalence by region, age, and sex among Chinese adults aged 40 years or older, 2014–2015*.
Figure 1 shows the age- and sex-specific COPD prevalence. The prevalence of COPD in the overall population was 13.6%, and it increased with age and was consistently higher among men than women in all age groups. COPD prevalence was highest among men aged 75 years or older (42.9%) and the lowest among women aged 40 to 44 (3.1%).
Figure 1. Age- and sex-specific chronic obstructive pulmonary disease (COPD) prevalence among Chinese adults aged 40 years or older, 2014–2015.
Table 1 shows the prevalence of COPD by region, age, and sex. In all age and gender groups, the prevalence was highest in the West, followed by the East, with the lowest prevalence in Central. Men aged 70 years or older in the West had the highest prevalence (49.0%), while women aged 40 to 49 years in Central had the lowest prevalence (3.2%).
Region-specific prevalence of COPD and different disease stages are presented in Figure 2. The prevalence of COPD was 13.7%, 10.9%, and 16.9% in the East, Central, and West, respectively. In the overall patients, the prevalence of mild disease (GOLD stage I), moderate disease (GOLD stage II), severe disease (GOLD stage III), and very severe disease (GOLD stage IV) were 7.7%, 4.9%, 0.9%, and 0.1%, respectively. The prevalence of moderate and more severe disease were 6.0%, 5.4%, and 6.7% in the East, Central, and West, respectively.
|①||East: Beijing, Tianjin, Hebei, Shanghai, Jiangsu, Zhejiang, Fujian, Liaoning, Shandong, Guangdong, and Hainan. Central: Shanxi, Anhui, Jiangxi, Heilongjiang, Jilin, Henan, Hubei, and Hun. West: Inner Mongolia, Guangxi, Chongqing, Sichuan, Guizhou, Yunnan, Tibet, Shaanxi, Gansu, Qinghai, Ningxia, and Xinjiang. There are two reasons for this division. First, the East, Central, and West have the significantly different levels of economic development across China. It is a traditional geographical classification in disease surveillance in China. Second, the sample of 125 DSPs in the national COPD surveillance were selected based on the stratification of all DSPs into the East, Central, and West across the country.|