Table 1. Summary of smoking adjustment factors (SAF) and the population attributable fraction (PAF) due to smoking for the major causes of deaths to the lungs.
Causes of death | OR (95% CI for ever | Population | Smoking adjustment | factors (SAF)d |
smokersa | attributable fraction | Never smokers | Ever smokers | |
Lung cancer | 4.99 (4.00–6.22) | 0.672 | 3.05 | 0.61 |
Chronic obstructive pulmonary diseases | 3.68 (2.58–5.26) | 0.579 | 2.37 | 0.65 |
Silicosisb | 1.80 (1.20–2.60) | 0.294 | 1.42 | 0.78 |
Pulmonary heart diseasec | 1.78 (1.36–2.33) | 0.286 | 1.40 | 0.79 |
Pulmonary tuberculosis | 2.54 (1.24–5.22) | 0.441 | 1.79 | 0.70 |
Abbreviations: OR, odds ratio (ever smoking vs. never smokers); 95% CI, 95% confidence interval.
All the odds ratios other than silicosis for smoking (ever vs. never smoking) was obtained from a case-control study of all adult deaths in Hong Kong [17].
We assumed Hong Kong male smokers having the same risk of silicosis as those of Italy ceramic workers; however, we had to use the incidence OR for silicosis (smoking vs. never smoking) to represent the mortality OR, as we do not have relevant mortality data in Hong Kong [18].
The odds ratio of other vascular disease was used to estimate the SAF-corrected SMR for pulmonary heart disease [17].
The SAF for smoking silicotics was numerically equal to 1/[(1-PAR%)RR] and that for nonsmoking silicotics was 1/(1-PAR%) (detailed calculations were illustrated in Supplement S1).