Hazard ratios (HR) for chronic obstructive pulmonary disease among male construction workers according to different exposures based on a Poisson regression analysis
| Predictor (exposure) | HR (95% CI) |
| Inorganic dust | 1.10 (1.06–1.14) |
| Gases and irritants | 1.02 (0.96–1.08) |
| Fumes | 0.98 (0.93–1.03) |
| Wood dust | 0.77 (0.64–0.92) |
| Age# | 5.47 (5.30–5.64) |
| Current smoking | 15.3 (11.2–20.8) |
| Ex-smoking | 2.94 (2.09–4.13) |
| Unknown smoking habits | 6.87 (4.95–9.56) |
CI: confidence interval
#: HR corresponds to an increase in age of 10 yrs