Pooled rate ratios (RRs) and 95 % confidence intervals (95% CIs) for the associations of daily air pollution levels with hospitalisation for first acute myocardial infarction
| Pollutant | Lag | All five cities RR* (95% CI) | Three cities with HDR‡ RR* (95% CI) |
|---|---|---|---|
| *Rate ratios calculated for a change of 10 000 particles/cm3 in PNC, 10 μg/m3 in PM10, 0.2 mg/m3 in CO, 8 μg/m3 in NO2, and 15 μg/m3 in O3. | |||
| †City-specific results heterogeneous (p<0.1), random effects model used for pooling. | |||
| ‡Hospital discharge register. | |||
| §Rate ratios for the 8 h O3 during warm season (April–September). | |||
| CO | 0 | 1.005 (1.000–1.010) | 1.007 (1.001–1.012) |
| 1 | 1.002 (0.996–1.007) | 1.002† (0.996–1.008) | |
| 2 | 1.002 (0.997–1.007) | 1.003 (0.998–1.009) | |
| 3 | 0.998 (0.992–1.003) | 1.004† (0.988–1.020) | |
| NO2 | 0 | 0.996 (0.988–1.005) | 0.999 (0.989–1.008) |
| 1 | 0.998† (0.986–1.010) | 0.998† (0.982–1.015) | |
| 2 | 1.003 (0.994–1.011) | 1.005 (0.996–1.015) | |
| 3 | 1.001† (0.989–1.014) | 1.005† (0.989–1.021) | |
| PNC | 0 | 1.005 (0.996–1.015) | 1.013 (1.000–1.026) |
| 1 | 0.997† (0.982–1.012) | 0.995† (0.953–1.039) | |
| 2 | 0.999 (0.990–1.008) | 1.001 (0.989–1.014) | |
| 3 | 0.998† (0.979–1.017) | 1.009† (0.974–1.046) | |
| PM10 | 0 | 1.003 (0.995–1.011) | 1.003 (0.994–1.012) |
| 1 | 1.001† (0.990–1.011) | 0.997 (0.988–1.006) | |
| 2 | 1.002 (0.994–1.010) | 1.003 (0.995–1.012) | |
| 3 | 1.002† (0.991–1.013) | 1.003† (0.986–1.020) | |
| O3 | 0 | 0.991 (0.979–1.003) | 0.989 (0.976–1.003) |
| 1 | 0.992 (0.980–1.004) | 0.991 (0.978–1.004) | |
| 2 | 0.997 (0.985–1.010) | 1.002 (0.988–1.015) | |
| 3 | 1.002 (0.990–1.015) | 1.002 (0.989–1.015) | |