Table 3.
Summary of results for co-pollutant adjustment for PM2.5 chemical constituents and associations with cardiovascular or respiratory hospital admissions, for constituents with significant associations in single-pollutant models.
Pollutant | Admission | Lag | Single-pollutant effecta [% (95% CI)] | Co-pollutant adjustment | ||
---|---|---|---|---|---|---|
Robustbto adjustment by | Not robustbto adjustment by | Range of central effect estimates (%) | ||||
Ca | Cardiovascular | 0 | 1.65 (0.50, 2.82) | Br, Cl, K, Ni, S, Zn | V | 1.18–2.01 |
BC | Cardiovascular | 0 | 4.83 (3.08, 6.62) | Al, Br, Cl, K, Ni, S, Si, Ti, V | NA | 4.48–6.00 |
V | Cardiovascular | 0 | 1.16 (0.43, 1.89) | Al, Br, Ca, Cl, K, S, Si, Ti, Zn | BC | 0.39–1.17 |
Zn | Cardiovascular | 0 | 0.95 (0.05, 1.86) | Cl | Al, Br, Ca, Ni, S, Si, Ti, V | 0.44–0.99 |
Al | Respiratory | 1 | 2.74 (1.62, 3.88) | Br, Cl, BC, Ni, K, S, V, Zn | NA | 1.99–4.34 |
Ca | Respiratory | 1 | 4.31 (2.61, 6.03) | Br, Cl, Ni, K, S, V, Zn | NA | 3.13–6.82 |
Cl | Respiratory | 0 | 0.24 (0.09, 0.39) | Al, Br, Ca, BC, Ni, K, S, Si, Ti, V, Zn | NA | 0.19–0.24 |
BC | Respiratory | 2 | 7.20 (4.64, 9.82) | Al, Br, Cl, Ni, K, S, Si, Ti, V | NA | 5.71–9.54 |
Ni | Respiratory | 0 | 2.92 (1.66, 4.19) | Al, Br, Ca, Cl, K, S, Si, Ti, Zn | BC | 1.34–3.21 |
Si | Respiratory | 1 | 2.41 (1.41, 3.42) | Br, Cl, BC, Ni, K, S, V, Zn | NA | 1.70–3.75 |
Ti | Respiratory | 1 | 3.47 (2.30, 4.65) | Br, Cl, BC, Ni, K, S, V, Zn | NA | 2.77–4.19 |
V | Respiratory | 1 | 2.75 (1.76, 3.75) | Al, Br, Ca, Cl, BC, K, S, Si, Ti, Zn | NA | 1.92–2.98 |
NA, not available. aSingle-pollutant effect is the increase in risk per IQR increase in pollutant. bIn this table, associations are considered robust to co-pollutant adjustment if they remained statistically significant; associations are not considered robust to co-pollutant adjustment if they lost statistical significance. |