Relative risks (RR) and 95% confidence intervals (CI) of dying from major diseases according to duration of smoking among cigarette smokers at recruitment compared with never-smokers as the referent group
| Cause of death | Duration of smoking (years) | p | |||||||
|---|---|---|---|---|---|---|---|---|---|
| ⩽20 | 21–30 | >30 | |||||||
| RR | (95% CI) | RR | (95% CI) | RR | (95% CI) | ||||
| All causes combined | 1.26 | (1.07–1.49) | 1.25 | (1.06–1.48) | 1.32 | (1.20–1.47) | <0.01 | ||
| Cancer | |||||||||
| All sites combined | 0.9 | (0.6–1.4) | 1.2 | (0.8–1.6) | 1.8 | (1.4–2.2) | <0.01 | ||
| Lip, oral cavity, and pharynx | 6-150 | 6.0 | (0.6–55.2) | 4.5 | (0.5–38.4) | 0.08 | |||
| Nasopharynx | 4.4 | (0.8–23.5) | 2.6 | (0.5–14.4) | 3.5 | (0.8–15.1) | 0.22 | ||
| Oesophagus | 6-150 | 2.4 | (0.7–8.9) | 1.3 | (0.5–3.4) | 0.43 | |||
| Stomach | 1.7 | (0.7–4.4) | 0.7 | (0.2–2.4) | 2.0 | (1.1–3.7) | 0.04 | ||
| Liver | 1.6 | (0.8–3.2) | 1.0 | (0.5–2.1) | 2.5 | (1.6–4.1) | <0.01 | ||
| Trachea, bronchus, and lung | 0.9 | (0.3–3.1) | 2.6 | (1.2–5.9) | 4.7 | (2.7–8.2) | <0.01 | ||
| Other diseases | |||||||||
| Ischaemic heart disease | 2.0 | (1.1–3.6) | 1.0 | (0.5–2.1) | 1.9 | (1.3–2.8) | 0.01 | ||
| Chronic obstructive pulmonary disease | 1.8 | (0.7–4.8) | 2.3 | (0.7–7.1) | 1.8 | (1.0–3.2) | 0.07 | ||
| Peptic ulcer | 5.4 | (0.5–56.1) | 16.9 | (2.8–103.5) | 8.7 | (1.7–45.6) | 0.07 | ||
↵6-150 Relative risk was not estimated due to the small number of deaths. All analyses were adjusted for age and other potential risk factors. See text for details.