Table 5.

Cumulative risk associated with susceptibility to smoking (N = 1,187)

	Overall
No. of risk factors	Odds Ratio*	95% Confidence Interval
0 (n = 131)	1.00
1 (n = 209)	0.98	0.37–2.61
2 (n = 278)	3.06	1.34–7.03
3 (n = 245)	3.88	1.69–8.88
4 (n = 155)	10.89	4.76–24.91
5 or more (n = 169)	25.67	11.30–58.34

* P for trend < 0.01.