HR and 95% CI per 1°C increase in wintertime temperature variability stratified by population characteristics in the prospective Chinese elderly cohort in Hong Kong, 1998–2010
| Stratified characteristics | Total respiratory (n=12 689) | Pneumonia (n=6672) | COPD (n=3075) | ||||||
| Cases | HR (95% CI) | PInteraction | Cases | HR (95% CI) | PInteraction | Cases | HR (95% CI) | PInteraction | |
| Age at entry, year | |||||||||
| ≤70 | 3596 | 1.26 (1.10 to 1.45) | 1599 | 1.27 (1.04 to 1.55) | 855 | 1.46 (1.10 to 1.94) | |||
| >70 | 9093 | 1.17 (1.05 to 1.30) | 0.28 | 5073 | 1.12 (0.97 to 1.28) | 0.19 | 2220 | 1.38 (1.12 to 1.71) | 0.69 |
| Sex | |||||||||
| Male | 5368 | 1.13 (1.02 to 1.26) | 2901 | 1.06 (0.92 to 1.22) | 1792 | 1.34 (1.09 to 1.66) | |||
| Female | 7321 | 1.24 (1.12 to 1.38) | 0.01 | 3771 | 1.22 (1.06 to 1.40) | 0.002 | 1283 | 1.49 (1.20 to 1.85) | 0.18 |
| Marital status | |||||||||
| Unmarried | 6802 | 1.20 (1.09 to 1.34) | 3607 | 1.17 (1.02 to 1.35) | 1536 | 1.46 (1.18 to 1.80) | |||
| Married | 5887 | 1.19 (1.07 to 1.32) | 0.68 | 3065 | 1.13 (0.98 to 1.30) | 0.40 | 1539 | 1.35 (1.09 to 1.68) | 0.34 |
| Education attainment | |||||||||
| Below primary | 6350 | 1.22 (1.10 to 1.35) | 3300 | 1.19 (1.04 to 1.37) | 1398 | 1.44 (1.16 to 1.78) | |||
| Primary | 4557 | 1.17 (1.05 to 1.31) | 0.28 | 2388 | 1.10 (0.95 to 1.28) | 0.13 | 1268 | 1.37 (1.10 to 1.71) | 0.55 |
| Secondary or above | 1782 | 1.14 (1.00 to 1.31) | 0.22 | 984 | 1.11 (0.93 to 1.32) | 0.30 | 409 | 1.38 (1.05 to 1.82) | 0.73 |
| Housing type | |||||||||
| Public and aided | 5544 | 1.19 (1.07 to 1.33) | 2862 | 1.22 (1.05 to 1.41) | 1403 | 1.43 (1.14 to 1.79) | |||
| Private | 5714 | 1.22 (1.10 to 1.35) | 0.53 | 3002 | 1.11 (0.97 to 1.28) | 0.06 | 1340 | 1.43 (1.16 to 1.77) | 0.98 |
| Other | 1431 | 1.15 (1.00 to 1.32) | 0.56 | 808 | 1.15 (0.96 to 1.37) | 0.44 | 332 | 1.27 (0.96 to 1.69) | 0.37 |
| Expenses/money in US$ | |||||||||
| Low (<128) | 1857 | 1.32 (1.16 to 1.50) | 1001 | 1.25 (1.05 to 1.48) | 427 | 1.34 (1.02 to 1.75) | |||
| Medium (128–384) | 8700 | 1.18 (1.07 to 1.31) | 0.03 | 4508 | 1.14 (1.00 to 1.31) | 0.17 | 2181 | 1.45 (1.19 to 1.78) | 0.43 |
| High (≥385) | 2132 | 1.17 (1.03 to 1.33) | 0.06 | 1163 | 1.12 (0.95 to 1.32) | 0.18 | 467 | 1.22 (0.93 to 1.59) | 0.51 |