Table 5.

The overall OR and 95% CI for independent and joint effects of smoking and alcohol drinking on esophageal cancer risk

Smoking (cig/day)	Ethanol intake (ml/week)				P for trend
	Never	1–249	250–499	≥500
Never	1.00	1.04 (0.68–1.59)	0.98 (0.64–1.51)	1.38 (0.97–1.98)	0.043
1–9	1.40 (1.07–1.83)	1.41 (0.94–2.12)	1.52 (1.07–2.17)	1.89 (1.45–2.46)	0.100
10–19	1.50 (1.10–2.04)	2.51 (1.53–4.10)	1.89 (1.27–2.82)	1.85 (1.35–2.55)	0.238
20–39	1.39 (1.06–1.83)	1.70 (0.99–2.90)	1.89 (1.34–2.66)	2.74 (2.15–3.48)	0.003
≥40	2.45 (1.20–4.96)	2.28 (0.36–14.2)	2.04 (0.53–7.89)	7.32 (4.58–11.7)	0.021
P for trend	0.001	0.024	0.021	<0.001	<0.001
P for interaction	0.016

Adjusted for age (continuous), gender, study area, previous income (continuous), BMI (continuous), and family history of cancer