Carotenoids, vitamin A and risk of adenomatous polyp recurrence in the polyp prevention trial

Int J Cancer. 2004 Nov 1;112(2):295-305. doi: 10.1002/ijc.20364.

Abstract

One trial reported beta-carotene supplementation was protective of adenomatous polyp recurrence in nonsmokers. We now examine the relation of serum and dietary carotenoids and vitamin A to adenomatous polyp recurrence in a subcohort of 834 participants in a low fat, high fiber, high fruit and vegetable dietary intervention, the Polyp Prevention Trial. Multivariate odds ratio (OR) and 95% confidence intervals (CI) of polyp recurrence were obtained using baseline or the average (first 3 years of the trial) carotenoid and vitamin A values after adjustment for covariates. Compared to the lowest quartile of baseline alpha-carotene concentrations, the OR of multiple polyp recurrence for the highest quartile was 0.55 (95% CI = 0.30-0.99) and the OR of right-sided recurrence was 0.60 (95% CI = 0.37-0.95). Baseline dietary intakes of alpha-carotene and vitamin A from food with/without supplements were inversely associated with any recurrence (p for linear trend = 0.03-alpha-carotene; p = 0.004 and p = 0.007 -intakes of vitamin A). Compared to the lowest quartile of averaged beta-carotene concentrations, the OR of multiple adenomas for the highest quartile was 0.40 (95% CI = 0.22-0.75) with an inverse trend (p = 0.02). The risk was inversely related to averaged: alpha-carotene concentrations and right-sided polyps; alpha-carotene intake and recurrence of any, multiple and right-sided polyps; beta-carotene intake and multiple adenoma recurrence; vitamin A from food (with supplements) and each adverse endpoint. Thus, alpha-carotene and vitamin A may protect against recurrence in nonsmokers and nondrinkers or be indicative of compliance or another healthy lifestyle factor that reduces risk.

Publication types

  • Clinical Trial
  • Multicenter Study
  • Randomized Controlled Trial

MeSH terms

  • Adenomatous Polyps / pathology*
  • Adenomatous Polyps / prevention & control*
  • Aged
  • Alcohol Drinking
  • Antioxidants / pharmacology*
  • Carotenoids / pharmacology*
  • Colonic Neoplasms / pathology*
  • Colonic Neoplasms / prevention & control*
  • Diet
  • Female
  • Humans
  • Life Style
  • Male
  • Middle Aged
  • Neoplasm Recurrence, Local / prevention & control*
  • Odds Ratio
  • Patient Compliance
  • Risk Factors
  • Smoking
  • beta Carotene / pharmacology*

Substances

  • Antioxidants
  • beta Carotene
  • Carotenoids