Table 1.
General characteristics of participants
| Characteristics | N | COPD prevalence n (%) | χ2 | p | |
|---|---|---|---|---|---|
| Gender | Male | 1916 | 349 (18.2) | 40.838 | <0.001 |
| Female | 2705 | 312 (11.5) | |||
| Age group (years) | 80–89 | 2159 | 352 (16.3) | 21.771 | <0.001 |
| 90–99 | 1608 | 226 (14.1) | |||
| ≥100 | 854 | 83 (9.7) | |||
| Residence | Urban | 2059 | 329 (16.0) | 8.494 | 0.004 |
| Rural | 2562 | 332 (13.0) | |||
| Ethic | Han | 4294 | 625 (14.6) | 3.117 | 0.077 |
| Minorities | 327 | 36 (11.0) | |||
| Education level | Illiterate | 3129 | 383 (12.2) | 34.147 | <0.001 |
| Primary school | 1182 | 224 (19.0) | |||
| Secondary school and above | 310 | 54 (17.4) | |||
| Marriage | Married | 1187 | 217 (18.3) | 20.906 | <0.001 |
| Widow | 3347 | 431 (12.9) | |||
| Divorce/unmarried | 87 | 13 (14.9) | |||
| Smoking | Current/past | 1213 | 237 (19.5) | 36.758 | <0.001 |
| Never | 3408 | 424 (12.4) | |||
| Alcohol drinking | Current/past | 1033 | 174 (16.8) | 7.001 | 0.008 |
| Never | 3588 | 487 (13.6) | |||
| Physical exercise≥0.5 h/day | Yes | 994 | 156 (15.7) | 1.996 | 0.158 |
| No | 3627 | 505 (13.9) | |||
| Self-rated good health | Yes | 1809 | 176 (9.7) | 50.762 | <0.001 |
| No | 2812 | 485 (17.2) | |||
| BADL disability | Yes | 1482 | 235 (15.9) | 4.291 | 0.038 |
| No | 3139 | 426 (13.6) | |||
| IADL disability | Yes | 3664 | 572 (15.6) | 4.275 | 0.039 |
| No | 957 | 126 (13.2) |
Abbreviations: BADL, activity of daily living; IADL, instrumental activity of daily living.