Table 3.

Adjusted odds ratios stratified by colorectal sub-site with corresponding 95% confidence intervals associated with various smoking exposures

Variable	Proximal Colon Cancer		Distal Colon Cancer		Rectal Cancer
	Adjusted Odds Ratio*		Adjusted Odds Ratio*		Adjusted Odds Ratio*
	OR	95% Confidence Interval	OR	95% Confidence Interval	OR	95% Confidence Interval
Smoking Status		N = 3,541		N =3,618		N = 3,957
Never	1.00	Referent	1.00	Referent	1.00	Referent
Former Smoker	1.20	0.83 – 1.68	1.34	0.91 – 1.91	1.17	0.85 – 1.61
Current Smoker	0.69	0.46 – 1.02	0.55	0.32 – 0.88	0.95	0.75 – 1.22
Amount Smoked		N = 3,544		N = 3,621		N = 3,960
Never Smoker	1.00	Referent	1.00	Referent	1.00	Referent
< 1 Pack/Day	0.90	0.52 – 1.56	0.77	0.48 – 1.25	1.01	0.73 – 1.39
1 Pack/Day	0.73	0.45 – 1.17	0.78	0.53 – 1.14	0.95	0.75 – 1.22
> 1 Pack/Day	0.81	0.44 – 1.48	0.46	0.25 – 0.84	1.19	0.88 – 1.60
Years Smoked		N = 3,587		N = 3,661		N = 4,003
Never Smoker	1.00	Referent	1.00	Referent	1.00	Referent
1–27 Years	0.94	0.59 – 1.49	0.73	0.48 – 1.12	0.92	0.69 – 1.22
28–41 Years	0.82	0.49 – 1.35	0.59	0.37 – 0.95	0.97	0.73 – 1.28
> 41 Years	0.52	0.28 – 0.97	0.71	0.44 – 1.16	1.13	0.87 – 1.47
Pack-Years		N = 3,544		N = 3,621		N = 3,960
Never Smoker	1.00	Referent	1.00	Referent	1.00	Referent
1–24 Pack-Years	0.82	0.50 – 1.36	0.84	0.56 – 1.26	0.94	0.69 – 1.26
25–45 Pack-Years	0.81	0.48 – 1.36	0.67	0.43 – 1.05	0.94	0.69 – 1.29
> 45 Pack-Years	0.72	0.40 – 1.30	0.56	0.33 – 0.97	1.26	0.92 – 1.72
Lifetime Tar Grams♪		N = 1,629		N = 1,664		N = 1,755
Never Smoker	1.00	Referent	1.00	Referent	1.00	Referent
1–3,133 Grams	1.43	0.69 – 2.95	0.77	0.37 – 1.61	1.26	0.76 – 2.07
3,133–8,989	0.63	0.24 – 1.68	1.05	0.55 – 2.02	0.89	0.51 – 1.55
> 8,989	1.10	0.48 – 2.53	0.59	0.25 – 1.41	1.15	0.67 – 1.97

^*Adjusted for race, age, gender, body mass index, county of residence, and other tobacco use.

^♪Lifetime Tar Grams = Brand Specific Tar Level * (Cigs/Day * 365) * Years