Table 4.
Random effects meta-analysis of the association between exposure to NO2, PM2.5, and O3 and the risk of progression of IPF
| Pollutant | Category | Study Characteristics (Number of association estimates) |
Summary RR (95%CI) | I2 (%) | p for heterogeneity |
|---|---|---|---|---|---|
| NO2 | Age | Age ≤ 70 (4) | 1.26 (1.09, 1.47) | 26.23 | 0.25 |
| Age >70 (4) | 1.41 (1.09, 1.82) | 56.65 | 0.07 | ||
| Female | Female <50 (8) | 1.32 (1.16, 1.50) | 38.58 | 0.12 | |
| Female ≥ 50 (0) | / | / | / | ||
| Smoke | Smoke <50 (4) | 1.49 (1.22, 1.81) | 22.66 | 0.27 | |
| Smoke ≥ 50 (4) | 1.21 (1.04, 1.42) | 36.63 | 0.19 | ||
| Region | Europe (4) | 1.30 (1.10, 1.53) | 28.14 | 0.24 | |
| Others (4) | 1.36 (1.07, 1.73) | 58.45 | 0.07 | ||
| Outcome | Incidence (3) | 1.67 (1.05, 2.66) | 36.93 | 0.20 | |
| Mortality (4) | 1.02 (0.96, 1.08) | 0.00 | 0.78 | ||
| Progression (8) | 1.32 (1.16, 1.50) | 38.58 | 0.12 | ||
| PM2.5 | Age | Age ≤ 70 (2) | 1.38 (1.12, 1.70) | 0.00 | 0.54 |
| Age >70 (3) | 1.15 (0.69, 1.82) | 78.52 | 0.01 | ||
| Female | Female <50 (5) | 1.23 (0.90, 1.70) | 69.05 | 0.01 | |
| Female ≥ 50 (0) | / | / | / | ||
| Smoke | Smoke <50 (2) | 1.01 (0.55, 1.86) | 88.19 | 0 | |
| Smoke ≥ 50 (3) | 1.51 (0.94, 2.44) | 48.17 | 0.15 | ||
| Region | Europe (3) | 1.49 (1.15, 1.94) | 11.34 | 0.32 | |
| Others (4) | 1.05 (1.02, 1.09) | 33.64 | 0.21 | ||
| Outcome | Incidence (2) | 1.67 (0.87, 3.19) | 71.19 | 0.06 | |
| Mortality (3) | 2.03 (0.48, 8.54) | 82.18 | 0.00 | ||
| Progression (7) | 1.08(1.01, 1.15) | 63.51 | 0.01 | ||
| O3 | Age | Age ≤ 70 (2) | 1.28 (0.96, 1.70) | 47.15 | 0.17 |
| Age >70 (2) | 1.14 (1.00, 1.30) | 0.00 | 0.40 | ||
| Female | Female <50 (4) | 1.19 (1.03, 1.38) | 29.05 | 0.24 | |
| Female ≥ 50 (0) | / | / | / | ||
| Smoke | Smoke <50 (2) | 1.14 (1.00, 1.30) | 0.00 | 0.40 | |
| Smoke ≥ 50 (2) | 1.28 (0.96, 1.70) | 47.15 | 0.17 | ||
| Outcome | Incidence (2) | 1.22 (0.94, 1.58) | 0 | 0.35 | |
| Mortality (3) | 0.97(0.88, 1.07) | 0.00 | 0.46 | ||
| Progression (4) | 1.19(1.03, 1.38) | 29.05 | 0.24 |