Ontology highlight
ABSTRACT: Background
Evidence from observational studies suggests that inadequate folate status enhances colorectal carcinogenesis, but results from some randomized trials do not support this hypothesis.Objective
To assess the effect of folic acid supplementation on recurrent colorectal adenoma, we conducted a cost-efficient, double-blind, randomized trial among participants of 2 large prospective cohorts, the Health Professionals Follow-Up Study and the Nurses' Health Study.Design
Participants were randomly assigned to receive folic acid (1 mg/d) (n = 338) or placebo (n = 334) for 3-6.5 y. The primary endpoint was any new diagnosis of adenoma during the study period (May 1996-March 2004). Secondary outcomes were adenoma by site and stage and number of recurrent adenomas. Associations were also examined by plasma folate concentrations at baseline.Results
Incidence of at least one recurrent adenoma was not significantly associated with folic acid supplementation [relative risk (RR): 0.82; 95% CI: 0.59,1.13; P = 0.22]. Among participants with low plasma folate concentrations at baseline (Conclusions
Our results do not support an overall protective effect of folic acid supplementation on adenoma recurrence. Folic acid supplementation may be beneficial among those with lower folate concentrations at baseline. This trial was registered at clinical trials.gov as NCT00512850.
SUBMITTER: Wu K
PROVIDER: S-EPMC2777472 | biostudies-literature | 2009 Dec
REPOSITORIES: biostudies-literature
Wu Kana K Platz Elizabeth A EA Willett Walter C WC Fuchs Charles S CS Selhub Jacob J Rosner Bernard A BA Hunter David J DJ Giovannucci Edward E
The American journal of clinical nutrition 20091028 6
<h4>Background</h4>Evidence from observational studies suggests that inadequate folate status enhances colorectal carcinogenesis, but results from some randomized trials do not support this hypothesis.<h4>Objective</h4>To assess the effect of folic acid supplementation on recurrent colorectal adenoma, we conducted a cost-efficient, double-blind, randomized trial among participants of 2 large prospective cohorts, the Health Professionals Follow-Up Study and the Nurses' Health Study.<h4>Design</h4 ...[more]