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Am Fam Physician. 2019;99(11):717

Clinical Question

Is aspirin or eicosapentaenoic acid (EPA) effective in preventing colorectal adenomas in patients with previous high-risk colorectal neoplasia?

Bottom Line

After 12 months, neither aspirin nor EPA, alone or in combination, are any better than placebo at preventing colorectal adenomas in patients with high-risk neoplasia. (Level of Evidence = 1b)


The Systematic Evaluation of Aspirin and Fish Oil (seAFOod) Polyp Prevention Trial was a factorial trial that randomized patients with high-risk colorectal neoplasms detected on screening colonoscopy. The included patients had three or more adenomas, one of which had to be 1 cm in diameter, or they had five or more smaller adenomas. The researchers randomized patients to receive EPA (1,000 mg twice daily; n = 179) plus placebo, aspirin (300 mg daily; n = 177) plus placebo, EPA plus aspirin (n = 177); or placebo plus placebo (n = 176). The researchers performed a follow-up colonoscopy 12 months after enrollment. Sixty-six patients (9%) did not have a follow-up colonoscopy and were excluded from the analysis. The rate of subsequent adenomas at follow-up was high (61% to 63%) and not statistically significantly different for each group. The rate of adverse events was low in all groups.

Study design: Randomized controlled trial (double-blinded)

Funding source: Government

Allocation: Concealed

Setting: Outpatient (any)

Reference: Hull MA, Sprange K, Hepburn T, et al.; seAFOod Collaborative Group. Eicosapentaenoic acid and aspirin, alone and in combination, for the prevention of colorectal adenomas (seAFOod Polyp Prevention trial): a multicentre, randomised, double-blind, placebo-controlled, 2 × 2 factorial trial. Lancet. 2018;392(10164):2583–2594.

POEMs (patient-oriented evidence that matters) are provided by Essential Evidence Plus, a point-of-care clinical decision support system published by Wiley-Blackwell. For more information, see Copyright Wiley-Blackwell. Used with permission.

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