Relative risks (RR) and 95% confidence intervals (CI) of dying from major diseases according to age of smoking initiation among cigarette smokers at recruitment compared with never-smokers as the referent group
| Cause of death | Age of smoking initiation (years) | p | |||||||
|---|---|---|---|---|---|---|---|---|---|
| ⩽20 | 21–24 | >24 | |||||||
| RR | (95% CI) | RR | (95% CI) | RR | (95% CI) | ||||
| All causes combined | 1.38 | (1.24–1.54) | 1.30 | (1.12–1.50) | 1.18 | (1.04–1.35) | <0.01 | ||
| Cancer | |||||||||
| All sites combined | 1.7 | (1.4–2.2) | 1.7 | (1.3–2.3) | 1.0 | (0.7–1.4) | <0.01 | ||
| Lip, oral cavity, and pharynx | 5.7 | (0.7–46.1) | 7-150 | 4.5 | (0.5–43.5) | 0.11 | |||
| Nasopharynx | 3.3 | (0.8–14.1) | 4.8 | (1.0–23.5) | 2.8 | (0.5–14.8) | 0.07 | ||
| Oesophagus | 1.3 | (0.5–3.6) | 1.5 | (0.4–5.3) | 1.1 | (0.3–4.0) | 0.62 | ||
| Stomach | 2.2 | (1.2–4.2) | 0.6 | (0.2–2.2) | 1.5 | (0.7–3.3) | 0.02 | ||
| Liver | 2.2 | (1.4–3.7) | 2.3 | (1.2–4.2) | 1.4 | (0.8–2.6) | <0.01 | ||
| Trachea, bronchus, and lung | 4.6 | (2.6–8.1) | 5.9 | (3.0–11.3) | 1.5 | (0.7–3.3) | <0.01 | ||
| Other diseases | |||||||||
| Ischaemic heart disease | 1.9 | (0.7–4.9) | 1.6 | (0.9–2.8) | 1.8 | (1.1–2.8) | 0.01 | ||
| Chronic obstructive pulmonary disease | 2.2 | (1.2–4.1) | 1.8 | (0.7–4.5) | 1.3 | (0.6–2.8) | 0.01 | ||
| Peptic ulcer | 8.5 | (1.5–46.6) | 4.1 | (0.3–50.4) | 10.9 | (2.3–52.2) | 0.07 | ||
↵7-150 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.