Cancer of the head and neck after exclusion of death from 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 | 2563 | 2 | Ref | 0.002 | Ref | 0.0007 |
Former smokers | 5375 | 9 | 2.01 (0.43 to 9.35) | 1.90 (0.41 to 8.81) | ||
Current smokers | 742 | 9 | 12.15 (2.50 to 58.93) | 11.99 (2.49 to 57.86) | ||
MD¶ | 3831 | 9 | 3.30 (0.71 to 15.30) | 3.48 (0.75 to 16.15) | ||
Asbestos exposure | ||||||
Duration (years) | 0.98 (0.95 to 1.02) | 0.30 | ||||
(0–20) | 1825 | 7 | Ref | 0.80 | – | |
(20–30) | 2364 | 7 | 0.82 (0.28 to 2.40) | – | ||
(30–40) | 5422 | 10 | 0.59 (0.21 to 1.63) | – | ||
≥40 | 2900 | 5 | 0.66 (0.19 to 2.22) | – | ||
CEI* (f.years/mL) | ||||||
For an increase to 10 f.years/mL | 1.03 (1.00 to 1.06) | 0.03 | 1.03 (1.01 to 1.06) | 0.02 |
Bold values indicate statistical significance.
*CEI: cumulative exposure index to asbestos.
†TSFE: time since first exposure (years).
‡N: overall number of subjects by category.
§C: overall number of deaths from head and neck cancer (update 31 December 2015).
¶MD: missing data.