Outcomes of Physician-Diagnosed COPD and Its Association With Smoking Among Urban and Rural Residents in Regional Mainland China

Category: COPD

nonsmokersThere were a total of 29,319 survey respondents from 15,300 households. The response rate among adults in the selected villages was 90.1%. There were no significant differences in terms of demographic variables between respondents and those who did not take part in this survey. The final sample was representative of the municipality by age, gender, and residential area. Urban and rural residents consisted of 67.7% and 32.3%, respectively. Moreover, 49.7% were men and 50.3% were women. The demographic characteristics of the participants are shown in Tables 1 and 2. The average pack-years of cigarettes smoked was 7,688 for urban smokers and 9,671 for rural smokers. Male smokers consumed 8,477 cigarettes on average, while female smokers consumed 7,045 cigarettes on average.

Table 3 presents the overall prevalence of known COPD and its association with TACS levels. The overall prevalence of diagnosed COPD was 5.9%, and it was significantly higher among smokers (7.30%) than nonsmokers (5.36%). A gradient increase in adjusted OR was found from participants with lower TACS levels to upper TACS levels (OR, 1.63; 95% CI, 1.37 to 1.95; OR, 1.40; 95% CI, 1.15 to 1.72; and OR, 1.25; 95% CI, 1.02 to 1.35 for smokers with upper, middle, and lower TACS levels relative to nonsmokers, respectively). Moreover, a dose-response association between COPD and TACS was still evident after adjusting for age, gender, area of residence, fuels, heating in winter, kitchen ventilation, passive smoking status, education level, occupation, family average income, drinking, cooking oil, BMI, and physical activity.

Table 4 shows the prevalence of diagnosed COPD by age, gender, and residential area within different TACS strata. The prevalence in men (7.2%) was significantly higher than in women (4.7%). For urban and rural participants, no statistical difference was detected between the overall and TACS-stratified COPD prevalence provided with Canadian Health&Care Mall. There was a gradient increase in COPD prevalence from younger to elder subjects, whether they were smokers or not.

Table 5 presents the gender-specific prevalence of diagnosed COPD by TACS categories, urban and rural area, and age. Compared with women, men were more likely to have COPD among nonsmokers and lower TACS group. A dose-response relationship between COPD prevalence and TACS was also found in women; however, only men with upper TACS had a significantly higher prevalence of COPD relative to nonsmokers in this population.

Canadian Health&Care Mall: Physician-Diagnosed COPD and Its Association With Smoking Among Urban and Rural Residents in Regional Mainland China

Table 1—Demographic Characteristics of Study Participants (n = 29,319)

Characteristics Data
Age, yr
35-49 45.0 (13,199)
50-64 33.9 (9,938)
a 65 21.1 (6,182)
Area of residence
Rural 67.7 (19,847)
Urban 32.3 (9,472)
Gender
Women 49.7 (14,575)
Men 50.3 (14,744)
Education, yr
0 to 9 67.0 (19,816)
10 to 12 18.7 (5,479)
a 13 13.7 (4,024)
Occupation!
Job 1 53.1 (15,562)
Job 2 12.7 (3,733)
Job 3 34.2 (10,024)
Family average income
Lower 33.0 (9,683)
Middle 30.6 (8,977)
Higher 36.4 (10,659)
Fuels
Electricity/gas 67.1 (19,670)
Coal/oil 1.8 (527)
Firewood/straw 31.1 (9,122)

Table 2—Smoking Status of Participants by Demographic Characteristics

Characteristics Total,No. TACS Level Pack-yr
Nonsmoker Low Middle High
Area
Urban 19,847 14,276(71.9) 2,143 (10.8) 1,830 (9.2) 1,598(8.1) 7,688.0 ± 81.8
Rural 9,472 6,178 (65.2) 833 (8.8) 1,056(11.1) 1,405 (14.8) 9,671.4 ± 109.1
Gender
Men 14,575 6,034 (41.4) 2,814 (19.3) 2,807 (19.2) 2,920 (20.0) 8,477.3 ± 67.1
Women 14,744 14,420 (97.8) 162 (1.1) 79 (0.5) 83 (0.6) 7,045.6 ± 388.6
Age, yr
35 to 49 13,199 8,935 (67.7) 1,907 (14.4) 1,672 (12.7) 685 (5.2) 6,218.5 ± 67.0
50 to 64 9,938 6,915 (69.6) 752 (7.6) 832 (8.4) 1,439 (14.5) 9,566.4 ± 111.0
> 65 6,182 4,604 (74.5) 317(5.1) 382 (6.2) 879 (14.2) 12,200.5 ± 204.1
Total 29,319 20,454 2,976 2,886 3,003 8,425.0 ± 66.3

Table 3—Prevalence of COPD and Its Association With TACS Levels in Nanjing, China

TACS Level Prevalence* Adjusted OR(95% CI)f
All 5.9 (1,744/29,319)
Nonsmokers 5.36 (1,097/20,454) 1
Lower, 18 to 5,255 pack-yr 5.38 (160/2,976) 1.24 (1.007 to 1.52)
Middle, 5,256 to 9,489 pack-yr 6.4 (184/2,886) 1.39 (1.13 to 1.70)
Upper, a 9,490 pack-yr 10.1 (303/3,003) 1.60 (1.34 to 1.92)

Table 4—Prevalence of COPD and Its Association With Age, Gender, and Living Area Stratified by TACS in Nanjing, China

TACS Level COPD
1Prevalence* Adjusted OR (95% CI)t
Age, yr Overall
35 to 49 2.3 (307/13,199) 1
50 to 64 6.1 (610/9,938) 2.64 (2.26 to 3.08)
> 65 13.4 (827/6,182) 6.52 (5.55 to 7.67)
Nonsmokers
35 to 49 2.1 (185/8,935) 1
50 to 64 5.2 (362/6,915) 2.53 (2.07 to 3.08)
> 65 11.9 (550/4,604) 6.32 (5.17 to 7.73)
Lower
35 to 49 2.8 (53/1,907) 1
50 to 64 6.4 (48/752) 2.04 (1.30 to 3.21)
> 65 18.6 (59/317) 7.33 (4.44 to 12.08)
Middle
35 to 49 3.0 (50/1,672) 1
50 to 64 8.9 (74/832) 2.85 (1.89 to 4.32)
> 65 15.7 (60/382) 5.16 (3.16 to 8.42)
Upper 35 to 49 2.8 (19/685) 1
50 to 64 8.8 (126/1,439) 3.64 (2.12 to 6.26)
a 65 18.0 (158/879) 8.08 (4.60 to 14.19)
Gender
All levels
Female 4.7 (698/14,744) 1
Male 7.2 (1,046/14,575) 1.29 (1.13 to 1.48)
Nonsmokers
Female 4.5 (647/14,420) 1
Male 7.5 (450/6,034) 1.40(1.21 to 1.63)
Lower
Female 13.0 (21/162) 1
Male 4.9 (139/2,814) 0.57 (0.32 to 1.01)
Middle
Female 16.5 (13/79) 1
Male 6.1 (171/2,807) 0.55 (0.26 to 1.14)
UpperFemale 20.5 (17/83) 1
Male 9.8 (286/2,920) 0.64 (0.35 to 1.19)
Area
All levels
Rural 4.4 (414/9,472) 1
Urban 6.7 (1,330/19,847) 1.25 (0.94 to 1.66)
Nonsmokers
Rural 3.5 (218/6,178) 1
Urban 6.2 (879/14,276) 1.41 (0.96 to 2.06)
Lower
Rural 3.6 (30/833) 1
Urban 6.1 (130/2,143) 1.41 (0.60 to 3.30)
Middle
Rural 4.3 (45/1,056) 1
Urban 7.6 (139/1,830) 1.58 (0.65 to 3.87)
UpperRural 8.6 (121/1,405) 1
Urban 11.4(182/1,598) 0.74 (0.39 to 1.40)

Table 5—Prevalence of COPD and Its Association With TACS, Living Area, and Age Stratified by Gender in Regional China

Variables COPD Among Women COPD Among Men
IPrevalence* Adjusted OR (95% CI)f IPrevalence* Adjusted OR (95% CI)f
TACS level
Nonsmokers 4.5 (647/14,420) 1 7.5 (450/6,034) 1
Lower 13.0 (21/162) 2.27 (1.36to3.77) 4.9 (139/2,814) 1.07(0.85 to1.34)
Middle 16.5 (13/79) 2.75 (1.38to5.48) 6.1 (171/2,807) 1.24 (0.998to1.54)
Upper 20.5 (17/83) 3.11 (1.71to5.65) 9.8 (286/2,920) 1.43(1.17 to1.73)
Area
Rural 3.2 (151/4,759) 1 5.6 (263/4,713) 1
Urban 5.5 (547/9,985) 1.39 (0.88to2.18) 7.9 (783/9,862) 1.14 (0.79 to1.66)
Age, yr
35 to 49 1.8 (121/6,662) 1 2.8 (186/6,537) 1
50 to 64 4.8 (236/4,889) 2.67 (2.09to3.42) 7.4 (374/5,049) 2.57 (2.10 to3.15)
> 65 10.7 (341/3,193) 6.20 (4.81to7.97) 16.3 (486/2,989) 6.37 (5.14 to7.90)
Tags: China Cigarette smoking COPD prevalence total amount of cigarettes smoked