Trial reportThe American journal of clinical nutrition2019
Folic acid supplementation and risk of colorectal neoplasia during long-term follow-up of a randomized clinical trial.
Trial report in The American journal of clinical nutrition, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT00272324 (Aspirin/Folate Prevention of Large Bowel Polyps), which is not on this map. Cited by 13 papers, 3 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Aspirin/Folate Prevention of Large Bowel Polyps
Who cites it
13 citing papers in PubMed, 3 syntheses or guidelines pooled it, 26 citations in OpenAlex.
- Pooled it
- Association between dietary factors and colorectal serrated polyps: a systematic review and meta-analysis.Frontiers in nutrition · 2023Pooled it
- Eflornithine for chemoprevention in the high-risk population of colorectal cancer: a systematic review and meta-analysis with trial sequential analysis.Frontiers in oncology · 2023Pooled it
- Folate promotes colorectal cancer progression by impairing CD8Journal of translational medicine · 2026Article
- Folate intake, tissue levels, and colorectal cancer deaths in a national cohort established before folic acid fortification.European journal of nutrition · 2025Article
- Exploring the Mechanism of Canmei Formula in Preventing and Treating Recurrence of Colorectal Adenoma Based on Data Mining and Algorithm Prediction.Biological procedures online · 2025Article
- Vitamins and minerals and their role in cancer: a comprehensive review.Frontiers in nutrition · 2025Review
- Article
- Scientific opinion on the tolerable upper intake level for folate.EFSA journal. European Food Safety Authority · 2023Article
- Design of Cereal Products Naturally Enriched in Folate from Barley Pearling By-Products.Nutrients · 2022Article
- Association of folate intake and colorectal cancer risk in the postfortification era in US women.The American journal of clinical nutrition · 2021Article
- Vitamin Substitution Beyond Childhood—Requirements and RisksDeutsches Arzteblatt international · 2020Review
- How Often do Medical Specialties Question the Practices that They Perform? An Empirical, Cross-Sectional Analysis of the Published Literature.Inquiry : a journal of medical care organization, provision and financingArticle
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
12 authors at 8 institutions in 2 countries.
Funding
Abstract
backgroundThe Aspirin/Folate Polyp Prevention Study previously found folic acid increased risk of advanced and multiple colorectal adenomas during a surveillance colonoscopy interval starting about 3 y after randomization.
objectiveWe conducted secondary analyses to evaluate folic acid effects with additional follow-up after treatment was stopped.
methodsIn total, 1021 participants recently diagnosed with colorectal adenomas were randomly assigned to 1 mg/d of folic acid (n = 516) or placebo (n = 505), with or without aspirin, beginning 6 July 1994. The original 3-y treatment period was extended into a subsequent colonoscopy interval, but eventually stopped prematurely on 1 October 2004. With additional post-treatment follow-up, a total of 663 participants who extended treatment completed a second colonoscopic surveillance interval after the initial 3-y follow-up. In addition, 490 participants provided information regarding a subsequent surveillance colonoscopy occurring before completion of follow-up on 31 May 2012, including 325 who had agreed to extended treatment. Study endpoints included conventional adenomas, sessile serrated adenomas/polyps (SSA/Ps), or colorectal cancer, and RRs with 95% CIs were adjusted for baseline characteristics associated with availability of follow-up.
resultsAmong those who extended treatment, any colorectal neoplasia was found in 118 (36%) participants assigned to placebo and 146 (43%) assigned to folic acid during the second surveillance interval (RR: 1.21; 95% CI: 0.99, 1.47; P = 0.06). Increased risk of SSA/P with extended folic acid supplementation was statistically significant during the second surveillance interval (RR: 1.94; 95% CI: 1.02, 3.68; P = 0.04). There was no evidence of post-treatment effects for any colorectal neoplasia (RR: 1.01; 95% CI: 0.80, 1.28; P = 0.94), and the post-treatment effect for SSA/P was no longer statistically significant (RR: 1.38; 95% CI: 0.59, 3.19; P = 0.46).
conclusionsDelayed treatment effects were not observed, but folic acid may increase SSA/P risk. This trial was registered at clinicaltrials.gov as NCT00272324.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.