From the Guidelines
Low-dose aspirin is effective in preventing colon polyps, particularly in individuals younger than 70 years with a life expectancy of at least 10 years and a 10-year cardiovascular disease risk of at least 10%. According to the most recent and highest quality study 1, low-dose aspirin has been shown to reduce the incidence of colorectal neoplasia, including adenoma and sessile serrated lesion, with an odds ratio of 0.60 and a relative risk of 0.81, respectively. The study suggests that aspirin's anti-inflammatory properties and its ability to inhibit cyclooxygenase enzymes contribute to its protective effect against colon polyps.
The benefits of low-dose aspirin in preventing colon polyps include:
- Reduced incidence of adenoma recurrence by about 40% (odds ratio, 0.60; 95% CI, 0.36–0.98) 1
- Decreased incidence of sessile serrated lesions (IRR, 0.46; 0.25–0.87) 1
- Potential reduction in colorectal cancer mortality, as suggested by the study's best practice advice statements 1
However, the use of low-dose aspirin for colon polyp prevention also carries potential risks, including:
- Gastrointestinal or intracranial bleeding, with an increased risk of major gastrointestinal bleeding (OR, 1.59; 1.32–1.91) and intracranial bleeding (OR, 1.34; 1.07–1.70) 1
- Increased risk of bleeding in individuals older than 70 years, highlighting the need for careful consideration of individual risk factors 1
In light of these findings, the decision to take low-dose aspirin for colon polyp prevention should be made in consultation with a healthcare provider, taking into account individual risk factors for both colorectal cancer and aspirin-related complications. The regimen typically involves taking 81 mg of aspirin daily on a long-term basis, but this should be personalized based on the individual's specific health situation 1.
From the Research
Effectiveness of Low-Dose Aspirin in Preventing Colon Polyps
- The use of low-dose aspirin has been associated with a reduced risk of colorectal cancer (CRC) and colon polyps in several studies 2, 3, 4, 5, 6.
- A Danish population-based cohort study found that low-dose aspirin users had a higher risk of lower gastrointestinal bleeding, which may lead to earlier detection and removal of colon polyps, potentially reducing the risk of CRC 2.
- Another study found that new users of low-dose aspirin had a higher prevalence of conventional and serrated polyps compared to non-users, suggesting that aspirin may increase the detection of colorectal polyps 3.
- A double-blind, randomized clinical trial found that low-dose aspirin tended to reduce the growth of colorectal polyps in patients with familial adenomatous polyposis (FAP) 4.
- Observational studies have also suggested that regular use of aspirin is associated with a reduced risk of developing colorectal adenomas and cancer 5, 6.
Mechanism of Action
- Aspirin's chemopreventive effects on colon cancer and polyps are thought to be due to its inhibition of cyclooxygenase-2 (COX-2) 5, 6.
- The use of low-dose aspirin may cause premalignant polyps to bleed, leading to earlier detection and removal through colonoscopy and polypectomy 2.
Clinical Implications
- The use of low-dose aspirin may be associated with a reduced risk of colon polyps and CRC, particularly in patients with a high risk of developing these conditions 2, 3, 4, 5, 6.
- However, the use of low-dose aspirin also increases the risk of lower gastrointestinal bleeding, which must be carefully monitored and managed 2, 3.