Incidence of head and neck cancer after exclusion of subjects with a laryngeal cancer according to asbestos exposure and smoking status in the entire cohort (Cox models, N=12 685–176 256 subjects years)
| Cancer of the head and neck after exclusion of subjects with a laryngeal cancer | ||||||
| Number | Univariate model | Final model adjusted for smoking, CEI* and TSFE† | ||||
| N‡ | C§ | HR(95% CI) | P value | HR(95% CI) | P value | |
| Smoking status (baseline) | ||||||
| Never smokers | 2611 | 14 | Ref | <0.001 | Ref | <0.001 |
| Former smokers | 5340 | 29 | 1.03 (0.54 to 1.94) | 1.00 (0.53 to 1.89) | ||
| Current smokers | 735 | 18 | 4.32 (2.09 to 8.94) | 4.27 (2.07 to 8.82) | ||
| MD¶ | 3999 | 41 | 2.04 (1.11 to 3.73) | 2.09 (1.14 to 3.84) | ||
| Asbestos exposure | ||||||
| Duration (years) | 0.99 (0.97 to 1.01) | 0.30 | ||||
| (0–20) | 1841 | 19 | Ref | 0.80 | – | |
| (20–30) | 2413 | 22 | 0.96 (0.51 to 1.79) | – | ||
| (30–40) | 5508 | 41 | 0.82 (0.47 to 1.45) | – | ||
| ≥40 | 2923 | 20 | 0.74 (0.39 to 1.43) | – | ||
| CEI* (f.years/mL) | ||||||
| For an increase of 10 f.years/mL | 1.02 (0.99 to 1.03) | 0.08 | 1.02 (1.00 to 1.04) | 0.04 | ||
Bold values indicate statistical significance.
*CEI: cumulative exposure index to asbestos (f.years/mL).
†TSFE : time since first exposure (years).
‡N: overall number of subjects by category.
§C: overall number of incident cases of cancer of the head and neck (update 1 July 2019).
¶MD: missing data.