Table 1. Characteristics of CKB Participants at Baseline Survey by Study Areasa.
| Variables | Qingdao | Harbin | Haikou | Suzhou | Liuzhou | Pengzhou | Maiji | Huixian | Tongxiang | Liuyang | All |
|---|---|---|---|---|---|---|---|---|---|---|---|
| N | 35,500 | 57,548 | 29,686 | 53,269 | 50,174 | 55,677 | 49,884 | 63,353 | 57,701 | 59,897 | 512,689 |
| Age (years) | |||||||||||
| 30–49 | 47.7% | 39.8% | 40.1% | 39.7% | 32.9% | 41.2% | 50.6% | 45.9% | 37.8% | 42.0% | 41.7% |
| 50–69 | 45.7% | 48.0% | 47.6% | 53.1% | 56.6% | 52.5% | 44.6% | 47.7% | 54.8% | 50.5% | 50.3% |
| >70 | 6.6% | 12.2% | 12.3% | 7.2% | 10.5% | 6.3% | 4.9% | 6.4% | 7.4% | 7.5% | 8.0% |
| Mean ± SD | 50.8 ± 10.2 | 53.4 ± 11.4 | 53.1 ± 11.7 | 52.1 ± 10.3 | 54.2 ± 10.4 | 51.5 ± 10.5 | 49.4 ± 10.8 | 50.9 ± 10.4 | 52.8 ± 9.9 | 52.1 ± 10.6 | 52.0 ± 10.7 |
| Sex | |||||||||||
| Male | 43.6% | 39.9% | 36.2% | 41.9% | 38.1% | 38.4% | 39.9% | 44.2% | 41.6% | 44.1% | 41.0% |
| Female | 56.4% | 60.1% | 63.8% | 58.1% | 61.9% | 61.6% | 60.1% | 55.8% | 58.4% | 55.9% | 59.0% |
| BMI (kg/m2) | |||||||||||
| <18.5 | 0.8% | 2.6% | 6.3% | 2.6% | 3.5% | 4.5% | 6.4% | 2.6% | 6.0% | 8.4% | 4.4% |
| 18.5–24.9 | 43.6% | 55.0% | 64.3% | 62.0% | 63.9% | 68.6% | 72.2% | 58.7% | 69.7% | 72.3% | 63.7% |
| ≥25 | 55.6% | 42.3% | 29.4% | 35.4% | 32.6% | 26.8% | 21.4% | 38.7% | 24.3% | 19.3% | 32.0% |
| Mean ± SD | 25.7 ± 3.5 | 24.6 ± 3.4 | 23.3 ± 3.3 | 24.0 ± 3.2 | 23.8 ± 3.2 | 23.3 ± 3.2 | 22.7 ± 3.1 | 24.3 ± 3.5 | 22.9 ± 3.2 | 22.4 ± 3.1 | 23.7 ± 3.4 |
| Smoking status | |||||||||||
| Non-smoker | 65.9% | 60.7% | 71.9% | 61.7% | 64.1% | 51.5% | 63.1% | 62.7% | 61.6% | 62.8% | 61.9% |
| Occasional smoker | 2.9% | 6.3% | 6.1% | 4.6% | 8.2% | 8.1% | 4.1% | 7.6% | 3.8% | 4.5% | 5.7% |
| Ex-regular smoker | 7.4% | 8.4% | 4.4% | 5.6% | 6.3% | 7.1% | 2.8% | 5.7% | 7.4% | 3.7% | 6.0% |
| Current smoker | 23.9% | 24.6% | 17.6% | 28.0% | 21.3% | 33.3% | 29.9% | 24.0% | 27.2% | 29.0% | 26.4% |
| Passive smoking | |||||||||||
| Never | 38.1% | 20.3% | 56.6% | 14.0% | 19.2% | 11.4% | 18.1% | 21.0% | 43.4% | 21.3% | 24.5% |
| Former | 29.2% | 45.2% | 8.6% | 39.7% | 48.0% | 39.2% | 26.3% | 30.8% | 14.9% | 22.3% | 31.3% |
| Present | 32.7% | 34.5% | 34.8% | 46.3% | 32.8% | 49.4% | 55.6% | 48.2% | 41.7% | 56.4% | 44.2% |
| Drinking | |||||||||||
| Never | 37.3% | 24.3% | 66.0% | 59.5% | 33.7% | 33.4% | 65.7% | 19.5% | 65.0% | 63.7% | 45.9% |
| Ex-regular | 1.2% | 1.0% | 1.0% | 2.2% | 1.3% | 3.9% | 0.7% | 0.5% | 2.2% | 3.4% | 1.8% |
| Occasional | 37.0% | 41.5% | 23.6% | 17.1% | 45.2% | 31.8% | 28.0% | 60.6% | 13.2% | 17.5% | 31.8% |
| Monthly | 4.3% | 9.7% | 2.6% | 4.3% | 7.3% | 6.6% | 2.5% | 8.7% | 3.1% | 4.8% | 5.7% |
| Weekly | 20.2% | 23.5% | 6.7% | 16.9% | 12.5% | 24.3% | 3.1% | 10.7% | 16.5% | 10.6% | 14.9% |
| Physical activity (MET hours/day) | |||||||||||
| <10 | 8.8% | 10.4% | 12.5% | 4.6% | 7.3% | 3.6% | 3.1% | 10.9% | 2.5% | 4.1% | 6.5% |
| 10–19.9 | 24.9% | 22.3% | 27.3% | 13.2% | 21.3% | 10.6% | 7.4% | 21.9% | 7.4% | 25.3% | 17.5% |
| ≥20 | 66.3% | 67.3% | 60.2% | 82.2% | 71.4% | 85.8% | 89.5% | 67.1% | 90.1% | 70.6% | 76.0% |
| Mean ± SD | 18.1 ± 11.4 | 16.0 ± 10.9 | 13.6 ± 9.0 | 25.5 ± 15.2 | 16.9 ± 11.1 | 22.1 ± 11.8 | 28.5 ± 13.0 | 18.5 ± 15.3 | 30.2 ± 15.3 | 17.8 ± 11.4 | 21.1 ± 13.9 |
| Household income (Yuan) | |||||||||||
| <10,000 | 8.3% | 12.5% | 21.5% | 12.2% | 15.1% | 62.6% | 78.6% | 42.1% | 6.7% | 16.7% | 28.2% |
| 10,000-19,999 | 32.6% | 33.3% | 31.9% | 14.4% | 35.7% | 28.3% | 19.2% | 43.7% | 14.2% | 35.3% | 29.1% |
| 20,000-34,999 | 42.5% | 31.5% | 22.1% | 31.7% | 30.3% | 5.7% | 1.9% | 11.5% | 41.5% | 32.2% | 24.7% |
| ≥35,000 | 16.5% | 22.7% | 24.6% | 41.6% | 18.9% | 3.4% | 0.2% | 2.7% | 37.6% | 15.9% | 18.0% |
| Education | |||||||||||
| No formal school | 6.4% | 3.4% | 12.6% | 29.6% | 3.3% | 15.8% | 48.6% | 14.9% | 43.0% | 5.6% | 18.6% |
| Primary School | 19.2% | 9.1% | 19.0% | 32.1% | 18.3% | 49.3% | 26.3% | 36.7% | 36.2% | 58.6% | 32.2% |
| Middle School | 40.7% | 31.3% | 29.1% | 28.4% | 34.4% | 26.7% | 16.5% | 34.0% | 16.7% | 27.0% | 28.3% |
| High School/above | 33.7% | 56.2% | 39.3% | 9.9% | 44.0% | 8.2% | 8.6% | 14.4% | 4.1% | 8.8% | 21.0% |
| Self-rated health | |||||||||||
| Excellent | 21.7% | 30.6% | 11.2% | 29.0% | 14.8% | 6.9% | 21.2% | 12.4% | 15.6% | 12.7% | 17.6% |
| Good | 29.3% | 19.1% | 20.7% | 32.0% | 18.4% | 30.6% | 28.0% | 31.1% | 43.6% | 24.1% | 28.1% |
| Fair | 43.8% | 40.0% | 61.4% | 28.6% | 56.5% | 41.5% | 39.2% | 42.9% | 36.2% | 56.0% | 43.9% |
| Poor | 5.3% | 10.3% | 6.6% | 10.4% | 10.3% | 20.9% | 11.6% | 13.6% | 4.5% | 7.2% | 10.4% |
| Heating fuels | |||||||||||
| Always clean | 4.1% | 28.2% | 0.1% | 18.9% | 13.9% | 16.4% | 0.1% | 0.2% | 0.6% | 0.3% | 8.6% |
| Unclean to clean | 32.0% | 62.4% | 0.0% | 0.7% | 7.5% | 2.6% | 0.8% | 1.1% | 0.0% | 5.8% | 11.3% |
| Always unclean | 59.7% | 4.3% | 0.1% | 0.1% | 8.7% | 6.5% | 94.2% | 81.9% | 0.0% | 92.9% | 36.2% |
| Never used heating | 0.2% | 0.0% | 97.8% | 79.1% | 58.1% | 70.3% | 0.4% | 2.6% | 99.3% | 0.5% | 38.9% |
| Others | 3.9% | 5.1% | 2.1% | 1.3% | 11.8% | 4.2% | 4.5% | 14.2% | 0.1% | 0.6% | 5.0% |
| Cooking fuels | |||||||||||
| Always clean | 56.4% | 38.7% | 31.7% | 15.2% | 34.1% | 4.6% | 0.4% | 0.6% | 14.0% | 0.5% | 16.9% |
| Unclean to clean | 22.0% | 33.9% | 17.8% | 45.7% | 42.9% | 9.3% | 1.0% | 0.8% | 14.9% | 1.6% | 19.0% |
| Always unclean | 0.4% | 1.3% | 14.1% | 14.5% | 3.0% | 55.5% | 58.6% | 63.0% | 35.2% | 65.4% | 34.2% |
| Never cooked | 17.2% | 20.8% | 31.9% | 15.5% | 11.8% | 26.6% | 37.8% | 30.4% | 33.7% | 29.3% | 25.1% |
| Others | 3.9% | 5.4% | 4.5% | 9.0% | 8.2% | 4.0% | 2.1% | 5.2% | 2.2% | 3.1% | 4.8% |
| PM2.5 (μg/m3) | |||||||||||
| Mean ± SD | 57.1 ± 0.9 | 55.3 ± 1.3 | 26.3 ± 0.4 | 57.7 ± 1.6 | 45.3 ± 0.9 | 51.4 ± 4.0 | 39.1 ± 2.0 | 70.9 ± 1.4 | 53.6 ± 1.1 | 51.3 ± 1.7 | 52.3 ± 10.6 |
| O3 (ppb) | |||||||||||
| Mean ± SD | 52.3 ± 2.4 | 43.3 ± 0.3 | 43.4 ± 1.3 | 59.6 ± 0.7 | 47.3 ± 0.7 | 59.7 ± 1.8 | 53.8 ± 0.4 | 60.6 ± 1.4 | 59.7 ± 1.0 | 53.0 ± 1.4 | 53.9 ± 6.4 |
a
Abbreviations: BMI, Body mass index; MET-hours, metabolic equivalent task hours. Note: All variables were adjusted by the age and sex of the study population where appropriate. Two-sided P values were derived from ANOVA for continuous variables and from the Chi-square test for categorical variables, all P values were < 0.005.