TABLE 4.

Risk of colorectal cancer or adenoma according to multivitamin use in the Nurses' Health Study (NHS) and the Health Professionals Follow-Up Study (HPFS)

	Colorectal cancer1		Colorectal adenoma2
Duration of multivitamin use3	No. of cases (NHS, HPFS)	Values4	No. of cases (NHS, HPFS)	Values5
Never	430, 303	1.00	785, 670	1.00
Past	279, 199	0.99 (0.82, 1.21)	686, 535	0.96 (0.88, 1.04)
Current
1–5 y	334, 172	0.96 (0.81, 1.13)	763, 570	0.91 (0.80, 1.03)
6–9 y	86, 88	0.89 (0.75, 1.06)	303, 215	0.73 (0.66, 0.81)
10–15 y	84, 121	0.89 (0.76, 1.05)	233, 293	0.80 (0.72, 0.90)
16–19 y	26, 48	0.71 (0.53, 0.96)	110, 121	0.90 (0.71, 1.14)
≥20 y	73, 52	0.77 (0.64, 0.94)	221, 144	0.76 (0.65, 0.89)

¹A Cox proportional hazards model was used and adjusted for age, calendar year, pack-years of smoking before age 30 y, physical activity, aspirin dose, height, BMI, family history of colorectal cancer in parents and siblings, menopausal status and hormone therapy use, history of endoscopy, and intakes of red meat, alcohol, calcium from foods, and total energy.

²A logistic regression model was used and adjusted for age, endoscopy before baseline, recent endoscopy year, pack-years of smoking before age 30 y, physical activity, aspirin dose, height, BMI, family history of colorectal cancer in parents and siblings, menopausal status and hormone therapy use, red meat intake, alcohol intake, calcium intake from foods, total energy intake, and indication for endoscopy.

³Calculated on the basis of the reported duration at baseline and updated by subsequent responses to current multivitamin use.

⁴Values are pooled multivariate relative risks; 95% CIs in parentheses.

⁵Values are pooled multivariate odds ratios; 95% CIs in parentheses.