Selenium Supplementation for Prevention of Colorectal Adenomas and Risk of Associated Type 2 Diabetes.

TitleSelenium Supplementation for Prevention of Colorectal Adenomas and Risk of Associated Type 2 Diabetes.
Publication TypeJournal Article
Year of Publication2016
AuthorsLance P, Thompson PA, Ashbeck EL, Roe DJ, Fales L, Buckmeier J, Wang F, Bhattacharyya A, Hsu C-H, Chow HHSherry, Ahnen DJ, C Boland R, Heigh RI, Fay DE, Hamilton SR, Jacobs ET, Martinez MElena, Alberts DS
JournalJ Natl Cancer Inst
Date Published2016 12
KeywordsAdenoma, Aged, Colorectal Neoplasms, Cyclooxygenase 2 Inhibitors, Diabetes Mellitus, Type 2, Dietary Supplements, Female, Follow-Up Studies, Humans, Male, Medication Adherence, Middle Aged, Neoplasms, Second Primary, Risk Assessment, Selenium

BACKGROUND: Selenium supplementation may help to prevent colorectal cancer; as precursors of colorectal cancer, colorectal adenomas are a surrogate for colorectal cancer. Selenium supplementation may increase risk of type 2 diabetes (T2D).

METHODS: The Selenium and Celecoxib (Sel/Cel) Trial was a randomized, placebo controlled trial of selenium 200 µg daily as selenized yeast and celecoxib 400 mg once daily, alone or together, for colorectal adenoma prevention. Men and women between age 40 and 80 years were eligible following colonoscopic removal of colorectal adenomas. The primary outcome was adenoma development. Celecoxib was suspended because of cardiovascular toxicity in other trials, but accrual continued to selenium and placebo. A total of 1621 participants were randomly assigned to selenium or placebo, of whom 1374 (84.8%) were available for analysis. All statistical tests were two-sided.

RESULTS: In the respective placebo and selenium arms of 689 and 685 participants, adenoma detection after medians of 33.6 (range = 0.0-85.1 months) and 33.0 months (range = 0.0-82.6 months) were 42.8% and 44.1% (relative risk [RR] = 1.03, 95% confidence interval [CI] = 0.91 to 1.16, P = .68). In participants with baseline advanced adenomas, adenoma recurrence was reduced by 18% with selenium (RR = 0.82, 95% CI = 0.71 to 0.96, P = .01). In participants receiving selenium, the hazard ratio for new-onset T2D was 1.25 (95% CI = 0.74 to 2.11, P = .41), with a statistically significantly increased risk of selenium-associated T2D among older participants (RR = 2.21; 95% CI = 1.04 to 4.67, P = .03).

CONCLUSIONS: Overall, selenium did not prevent colorectal adenomas and showed only modest benefit in patients with baseline advanced adenomas. With limited benefit and similar increases in T2D to other trials, selenium is not recommended for preventing colorectal adenomas in selenium-replete individuals.

Alternate JournalJ. Natl. Cancer Inst.
PubMed ID27530657
PubMed Central IDPMC6272807
Grant ListP30 CA016672 / CA / NCI NIH HHS / United States
P30 CA023074 / CA / NCI NIH HHS / United States
R01 CA151708 / CA / NCI NIH HHS / United States
P01 CA041108 / CA / NCI NIH HHS / United States
Person Ref: