Format

Send to

Choose Destination
Cancer Epidemiol Biomarkers Prev. 2008 Aug;17(8):2136-45. doi: 10.1158/1055-9965.EPI-07-2895.

Vitamins B2, B6, and B12 and risk of new colorectal adenomas in a randomized trial of aspirin use and folic acid supplementation.

Author information

1
Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Harlyne J Norris Cancer Research Tower, 1450 Biggy Street Room 1509B, Los Angeles CA 90033, USA. janefigu@usc.edu

Abstract

BACKGROUND:

Folate, other vitamin B cofactors, and genes involved in folate-mediated one-carbon metabolism all may play important roles in colorectal neoplasia. In this study, we examined the associations between dietary and circulating plasma levels of vitamins B(2), B(6), and B(12) and risk colorectal adenomas.

METHODS:

The Aspirin/Folate Polyp Prevention Study is a randomized clinical trial of folic acid supplementation and incidence of new colorectal adenomas in individuals with a history of adenomas (n = 1,084). Diet and supplement use were ascertained through a food frequency questionnaire administered at baseline. Blood collected at baseline was used to determine plasma B-vitamin levels. We used generalized linear regression to estimate risk ratios (RR) and 95% confidence intervals (95% CI) as measures of association.

RESULTS:

We found a borderline significant inverse association with plasma B(6) [pyridoxal 5'-phosphate (PLP)] and adenoma risk (adjusted RR Q4 versus Q1, 0.78; 95% CI, 0.61-1.00; P(trend) = 0.08). This association was not modified by folic acid supplementation or plasma folate. However, the protective association of PLP with adenoma risk was observed only among subjects who did not drink alcohol (P(interaction) = 0.03). Plasma B(2) (riboflavin) was inversely associated with risk of advanced lesions (adjusted RR Q4 versus Q1, 0.51; 95% CI, 0.26-0.99; P(trend) = 0.12). No significant associations were observed between adenoma risk and plasma vitamin B(12) or dietary intake of vitamin B(2) and B(6). When we examined specific gene-B-vitamin interactions, we observed a possible interaction between methylenetetrahydrofolate reductase -C677T and plasma B(2) on risk of all adenomas.

CONCLUSION:

Our results suggest that high levels of PLP and B(2) may protect against colorectal adenomas.

PMID:
18708408
PMCID:
PMC2518404
DOI:
10.1158/1055-9965.EPI-07-2895
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center