Table 5.

HRs and 95% CIs for Incident Colorectal Cancer by BMI (kg/m²)

BMI Category*	Any Colorectal Cancer			Proximal Colon			Distal Colon			Rectum			Advanced			Nonadvanced
	Cases	HR	95% CI†	Cases	HR	95% CI†	Cases	HR	95% CI†	Cases	HR	95% CI†	Cases	HR	95% CI†	Cases	HR	95% CI†
All
18.5-24.9	284	1.00	Ref	157	1.00	Ref	65	1.00	Ref	56	1.00	Ref	112	1.00	Ref	157	1.00	Ref
25.0-29.9	424	1.11	0.95 to 1.29	228	1.10	0.89 to 1.35	101	1.13	0.82 to 1.56	92	1.17	0.83-1.64	151	1.03	0.80 to 1.32	256	1.18	0.97 to 1.45
≥ 30	254	1.24	1.04 to 1.47	144	1.32	1.04 to 1.66	53	1.07	0.73 to 1.55	52	1.20	0.81 to 1.78	100	1.27	0.96 to 1.67	141	1.22	0.96 to 1.54
P, trend‡	.02			.02			.70			.35			.10			.09
Men
18.5-24.9	128	1.00	Ref	65	1.00	Ref	31	1.00	Ref	31	1.00	Ref	54	1.00	Ref	68	1.00	Ref
25.0-29.9	270	1.19	0.96 to 1.48	136	1.15	0.85 to 1.55	64	1.19	0.77 to 1.85	68	1.27	0.83 to 1.96	86	0.92	0.65 to 1.29	173	1.41	1.06 to 1.87
≥ 30	148	1.48	1.16 to 1.89	74	1.48	1.05 to 2.09	36	1.48	0.90 to 2.42	35	1.38	0.83 to 2.27	53	1.32	0.89 to 1.95	85	1.53	1.11 to 2.13
P, trend‡	.002			.02			.12			.21			.19			.01
Women
18.5-24.9	156	1.00	Ref	92	1.00	Ref	34	1.00	Ref	25	1.00	Ref	58	1.00	Ref	89	1.00	Ref
25.0-29.9	154	1.07	0.86 to 1.34	92	1.10	0.82 to 1.47	37	1.13	0.70 to 1.81	24	1.04	0.59 to 1.83	65	1.22	0.85 to 1.75	83	1.01	0.74 to 1.36
≥ 30	106	1.03	0.80 to 1.33	70	1.23	0.89 to 1.69	17	0.66	0.36 to 1.21	17	0.95	0.50 to 1.79	47	1.24	0.83 to 1.84	56	0.96	0.68 to 1.36
P, trend‡	.74			.21			.25			.89			.27			.85
P, interaction by sex§	.12			.41			.27			.39			.90			.17

Abbreviations: BMI, body mass index; HR, hazard ratio; Ref, reference.

^*Results for BMI < 18.5 not shown owing to small numbers of cases.

^†Adjusted for age at baseline questionnaire completion (< 58, 58-61, 62-66, ≥ 67 years); sex (if applicable); study center; screening at baseline, T3, or T5 and prior to colorectal cancer diagnosis; screening adequacy and results at baseline, T3, or T5 screen and prior to colorectal cancer diagnosis (negative, positive for adenoma, inadequate/not done); race/ethnicity (white non-Hispanic, black non-Hispanic, Asian, other, missing); smoking status (never smoked tobacco, former cigarette smoker, current cigarette smoker, never smoked cigarettes but ever smoked a pipe or cigar, missing); and menopausal hormone therapy use (never, former, current, missing).

^‡Calculated by modeling BMI categories as continuous and evaluating statistical significance of Wald test; excludes BMI < 18.5.

^§Calculated by comparing the fit of a model including a cross-product term between BMI (continuous variable) and sex to a model without this term using the likelihood ratio test; models exclude BMI < 18.5.