Table 2.
Median all-cause mortality time stratified by stage at diagnosis and categorized fine particulate matter (PM2.5) exposure, and adjusteda hazard ratios for all-cause mortality from pooled and stage-specific Cox proportional hazard models with categorized PM2.5 and continuous PM2.5b.
| Median survival (years) | ||||||
|---|---|---|---|---|---|---|
| Number of patients |
Local | Regional | Distant | Overall | ||
| Categorized PM2.5 (µg/m3) | < 10 | 5364 | 2.16 | 0.61 | 0.18 | 0.83 |
| 10–15 | 7431 | 1.92 | 0.59 | 0.23 | 0.87 | |
| 15–20 | 3794 | 1.07 | 0.36 | 0.21 | 0.49 | |
| 20–25 | 1393 | 0.65 | 0.33 | 0.27 | 0.42 | |
| 25–30 | 386 | 0.25 | 0.15 | 0.12 | 0.19 | |
| ≥30 | 140 | 0.07 | 0.06 | 0.09 | 0.08 | |
| Overall | 1.52 | 0.48 | 0.20 | 0.64 | ||
| Hazard Ratioa (95% confidence interval) | ||||||
| Categorized PM2.5 (µg/m3) | < 10 | REF | REF | REF | REF | |
| 10–15 | 1.04 (0.98 – 1.11) | 1.02 (0.95 – 1.10) | 0.93 (0.85 – 1.02) | 1.00 (0.96 – 1.04) | ||
| 15–20 | 1.35 (1.24 – 1.46) | 1.28 (1.17 – 1.40) | 0.97 (0.87 – 1.09) | 1.18 (1.12 – 1.24) | ||
| 20–25 | 2.06 (1.83 – 2.32) | 1.43 (1.25 – 1.64) | 0.94 (0.81 – 1.09) | 1.46 (1.36 – 1.57) | ||
| 25–30 | 3.85 (3.15 – 4.70) | 2.52 (2.00 – 3.17) | 1.68 (1.36 – 2.09) | 2.40 (2.14 – 2.69) | ||
| ≥30 | 10.24 (7.40 – 14.16) | 4.60 (3.28 – 6.45) | 2.60 (1.82 – 3.73) | 4.61 (3.87 – 5.50) | ||
| Continuous PM2.5b | 1.31 (1.26 – 1.35) | 1.19 (1.14 – 1.23) | 1.05 (1.01 – 1.10) | 1.18 (1.16 – 1.20) | ||
a
Adjusted for age, sex, race/ethnicity, marital status, socioeconomic status, rural–urban commuting area, distance to primary interstate highway, distance to primary US and state highways, month of diagnosis, year of diagnosis and initial treatments.
b
Hazard ratios are scaled to a 1 standard deviation increase in PM2.5 (equivalent to 5.0 µg/m3).