Table 3. Body mass index (BMI) in relation to lung cancer risk by smoking status, the Singapore Chinese Health Study 1993–2006.
|
Never smokers
|
Former smokers
|
Current smokers
|
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|---|---|---|---|---|---|---|---|---|---|
| BMI (kg m−2) | Cases | Ratea | HR (95% CI)b | Cases | Ratea | HR (95% CI)c | Cases | Ratea | HR (95% CI)c |
| ⩾28 | 23 | 78 | 1.00 | 11 | 152 | 1.00 | 15 | 217 | 1.00 |
| 24–<28 | 50 | 52 | 0.69 (0.42–1.13) | 40 | 217 | 0.98 (0.50–1.91) | 74 | 292 | 1.15 (0.66–2.01) |
| 20–<24 | 176 | 75 | 1.01 (0.65–1.56) | 82 | 208 | 0.85 (0.45–1.60) | 351 | 391 | 1.58 (0.94–2.65) |
| <20 | 38 | 60 | 0.93 (0.55–1.56) | 23 | 202 | 0.85 (0.41–1.75) | 159 | 503 | 1.91 (1.12–3.25) |
| P for trend | 0.31 | 0.46 | <0.0001 | ||||||
a
Rate per 100 000 person-years adjusted for age and sex.
b
Hazard ratios (HRs) were adjusted for age at baseline, sex, dialect group and year of interview, level of education, and dietary intake of β-cryptoxanthin; confidence interval (CI).
c
Further adjusted for number of cigarettes smoked day, number of years of smoking, and number of years since quitting smoking (for former smokers only).