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. 2024 Feb 22;10:e53170. doi: 10.2196/53170

Table 1.

Demographic characteristics of participants in this study.


Controls (n=2952) COPDa (n=2991) P value
Age (years), mean (SD) 59.17 (11.44) 59.50 (11.66) .27b
Sex, n (%) .82c

Female 1169 (39.60) 1175 (39.30)

Male 1783 (60.40) 1816 (60.70)
BMI (kg/m2), n (%) <.001c

<18.5 96 (3.30) 129 (4.30)

18.5-25 1682 (57) 1849 (61.80)

≥25 1174 (39.80) 1013 (33.90)
Education, n (%) <.001c

Primary and below 971 (32.90) 1227 (41)

Junior middle school 988 (33.50) 987 (33)

Senior high school 620 (21) 493 (16.50)

Bachelor and above 373 (12.60) 284 (9.50)
Place of residence, n (%) <.001c

City 1977 (67) 1875 (62.7)

Countryside 975 (33) 1116 (37.3)
Nation, n (%) .02c

Han Chinese 2897 (98.10) 2906 (97.20)

Other 55 (1.90) 85 (2.80)
Occupation, n (%) <.001c

Farmer 794 (26.90) 1172 (39.20)

Worker 850 (28.80) 678 (22.70)

Other 1308 (44.30) 1141 (38.10)
MSDPd, n (%) <.001c

No 2741 (92.90) 2686 (89.80)

Yes 211 (7.10) 305 (10.20)
Smoking, n (%) .79c

No 1540 (52.20) 1549 (51.80)

Yes 1412 (47.80) 1442 (48.20)
GOLDe, n (%) f

1 1685 (56.30)

2 1103 (36.90)

3 172 (5.80)

4 31 (1)
FEV1g, mean (SD) 2.67 (0.66) 2.13 (0.70) <.001b
FEV1/FVCh ratio, mean (SD) 80.44 (5.63) 61.18 (9.00) <.001b
AAHIi, mean (SD) 1.34 (2.39) 1.11 (1.18) <.001b
PM2.5j, mean (SD) 71.85 (13.64) 73.81 (15.95) <.001b
Childhood passive smoking, n (%) .049c

No 1184 (40.1) 1276 (42.7)

Yes 1768 (59.9) 1715 (57.3)
History of childhood pneumonia or bronchitis, n (%) <.001c

No 2842 (96.3) 2789 (93.2)

Yes 110 (3.7) 202 (6.8)
Coronary heart disease, n (%) .11c

No 2888 (97.8) 2906 (97.2)

Yes 64 (2.2) 85 (2.8)
Hypertension, n (%) .007c

No 2575 (87.2) 2677 (89.5)

Yes 377 (12.8) 314 (10.5)
Diabetes, n (%) .70c

No 2851 (96.6) 2895 (96.8)

Yes 101 (3.4) 96 (3.2)

aCOPD: chronic obstructive pulmonary disease.

bP value for 2-tailed t test.

cP value for chi-square test.

dMSDP: maternal smoking during pregnancy.

eGOLD: Global Initiative for Chronic Obstructive Lung Disease.

fNot available.

gFEV1: forced expiratory volume in 1 second.

hFVC: forced vital capacity.

iAAHI (average annual household income) is measured in 10,000 Yuan (a currency exchange rate of 1 Chinese Yuan (CNY)=US $0.16147 is applicable).

jPM2.5: fine particulate matter.