Association between demographic characteristics and survival in the IPF cohort
| Demographic feature | Number of deaths (n=56) | Person years | Crude mortality rate (95% CI) | HR* (95% CI) | HR† (95% CI) |
|---|---|---|---|---|---|
| Sex | |||||
| Female | 13 | 67.1 | 193.8 (112.5 to 333.8) | 1.00 | 1.00 |
| Male | 43 | 193.4 | 222.4 (164.9 to 299.9) | 1.17 (0.63 to 2.18) p=0.615 | 1.16 (0.62 to 2.16) p=0.622 |
| Age category (years) | |||||
| <65 | 7 | 35.1 | 199.3 (95.0 to 418.0) | 1.00 | 1.00 |
| 65–69 | 8 | 47.2 | 169.4 (85.7 to 338.7) | 0.78 (0.28 to 2.15) | 0.77 (0.26 to 2.12) |
| 70–74 | 11 | 57.5 | 191.4 (106.0 to 345.6) | 0.92 (0.35 to 2.38) | 0.91 (0.35 to 2.36) |
| 75–79 | 19 | 67.2 | 282.7 (180.3 to 443.3) | 1.25 (0.52 to 2.98) | 1.24 (0.52 to 2.96) |
| 80–84 | 4 | 32.2 | 124.3 (46.6 to 331.1) | 0.56 (0.16 to 1.93) | 0.56 (0.16 to 1.93) |
| ≥85 | 7 | 21.2 | 330.1 (157.4 to 692.5) | 1.57 (0.55 to 4.50) p for trend=0.487 | 1.54 (0.54 to 4.43) p for trend=0.492 |
| % predicted FVC | |||||
| ≥101 | 8 | 42.8 | 186.8 (93.4 to 373.5) | 1.00 | 1.00 |
| 86–100 | 10 | 71.3 | 140.2 (75.4 to 260.5) | 0.68 (0.27 to 1.74) | 0.73 (0.28 to 1.89) |
| 71–85 | 17 | 89.5 | 190.0 (118.1 to 305.6) | 0.88 (0.38 to 2.06) | 0.90 (0.38 to 2.14) |
| ≤70 | 17 | 45.9 | 370.4 (230.2 to 595.8) | 1.66 (0.77 to 3.87) p for trend=0.524 | 1.77 (0.72 to 4.36) p for trend=0.588 |
| Missing values | 4 | – | – | – | – |
| % predicted Tlco | |||||
| ≥60 | 2 | 34.4 | 58.1 (14.5 to 232.4) | 1.00 | 1.00 |
| 46–59 | 8 | 24.4 | 94.7 (47.3 to 189.2) | 1.50 (0.32 to 7.05) | 1.54 (0.33 to 7.30) |
| 31–45 | 30 | 97.7 | 307.1 (214.7 to 439.2) | 4.72 (1.12 to 19.77) | 5.56 (1.31 to 23.60) |
| ≤30 | 8 | 24.4 | 327.4 (163.7 to 654.7) | 5.68 (1.20 to 26.88) p for trend=0.409 | 6.27 (1.31 to 30.06) p for trend=0.353 |
| Missing values | 8 | – | – | – | – |
| Anticoagulant status | |||||
| Never been on warfarin | 48 | 224.1 | 214.2 (161.4 to 284.2) | 1.00 | 1.00 |
| Previously on warfarin | 1 | 15.9 | 63.1 (8.9 to 447.6) | 0.28 (0.04 to 1.99) | 0.29 (0.04 to 2.28) |
| Currently on warfarin | 7 | 20.4 | 342.5 (163.3 to 718.5) | 1.32 (0.60 to 2.94) p=0.827 | 1.25 (0.56 to 2.79) p=0.865 |
| Smoking habit | |||||
| Never smoked | 16 | 71.0 | 225.5 (138.1 to 368.1) | 1.00 | 1.00 |
| Ex-smoker | 35 | 167.9 | 208.5 (149.7 to 290.4) | 0.90 (0.50 to 1.62) | 0.91 (0.49 to 1.69) |
| Current smoker | 5 | 21.6 | 231.7 (96.4 to 556.6) | 1.19 (0.44 to 3.27) p=0.966 | 1.17 (0.41 to 3.28) p=0.943 |
| Highly sensitive CRP (mg/mL) | |||||
| <1 | 4 | 22.9 | 174.8 (65.6 to 465.6) | 1.00 | 1.00 |
| 1–3 | 17 | 57.9 | 293.6 (182.5 to 472.3) | 1.42 (0.48 to 4.25) | 1.31 (0.43 to 3.94) |
| >3 | 32 | 174.7 | 183.1 (129.5 to 259.0) | 1.03 (0.37 to 2.92) p=0.904 | 0.98 (0.34 to 2.80) p=0.95 |
*HRs adjusted for a prothrombotic state.
†HRs adjusted for age, sex and a prothrombotic state.
CRP, C reactive protein; FVC, forced vital capacity; IPF, idiopathic pulmonary fibrosis; Tlco, carbon monoxide transfer factor.