Metastudies say aspirin lowers the risk of some cancers, but doubts remain

The new study presents the latest meta-analysis of published observational studies investigating whether long-term aspirin use reduces the risk of developing gastrointestinal cancer. Although the results suggest that aspirin may help prevent some cancers, some experts have found that this type of treatment, especially if recent randomized clinical trials reach very different conclusions. I am wondering how useful the related work in.

The use of aspirin as a preventative drug occurred in the second half of the 20th century. Initially considered to reduce the risk of heart attack and stroke, it has recently emerged as a possible cancer-preventing compound. However, evidence of the benefits of daily aspirin use is inconsistent and scientists are still arguing whether the risks outweigh the benefits.

A new study, led by a team of Italian researchers, focuses on a highly specific relationship between long-term use of aspirin and a reduction in the incidence of gastrointestinal cancer, the largest meta-analysis ever done. Is offered. The analysis pooled data from 113 observational studies targeting cancers such as intestines, pancreas, and liver.

The study defines regular use of aspirin as at least 1 or 2 tablets per week and concludes that there is a dose-dependent association between aspirin use and reduced risk of some cancers. I am. In general, aspirin use was associated with a 27% reduction in colorectal cancer risk, a 36% reduction in gastric cancer, and a 22% reduction in pancreatic cancer. Studies have shown that higher doses for longer periods have been associated with a significant reduction in cancer risk.

“We found that increasing the dose reduced the risk of cancer. Taking 75-100 mg aspirin daily reduced the risk of developing cancer by 10% compared to those who did not take aspirin” “The 325 mg dose per day,” Christina Bosetti, the corresponding author of the new study, said “500 mg daily was associated with a 35% reduction and a 50% reduction in risk.” States. There are some studies and need to be interpreted carefully. “

The analysis suggests that long-term use of aspirin is most beneficial in reducing cancer risk, especially in connection with colorectal cancer. The greatest benefit was seen when aspirin was used for 5-10 years, but researchers found that few studies have investigated aspirin use for very long periods (more than 10 years). Be careful.

“Compared to people who did not take aspirin regularly, those who took aspirin had a reduced risk of bowel cancer of up to 10 years,” Bosetti adds. “Risks decreased by 4% after 1 year, 11% after 3 years, 19% after 5 years and 29% after 10 years”

All these results sound like great news and may provide a green light to your daily use of aspirin, but it’s important to remember that there are many other studies.

Another large-scale meta-analysis of observational studies published earlier last year Daily aspirin use and cardiovascular eventsHowever, this analysis compared the potential benefits of aspirin with the known harm.
Data from 13 studies were pooled and their analysis concluded that there was a very small association between reduced cardiovascular events and aspirin use, but aspirin use was also associated with the occurrence of major bleeding events. Increased the rate. The general conclusion of that analysis is that daily use of aspirin may be harmful, especially if a person is healthy and not at high risk of cardiovascular disease.

Most of these studies rely on observational studies and are based on the correlation between regular aspirin use and disease incidence. The gold standard for identifying causality comes from randomized clinical trials, and one of the biggest themes to date has revealed interesting key results in 2018.

Called ASPREE trial (ASPirin in reducing events in the elderly), more than 19,000 subjects aged 70 years and older were followed for an average of 5 years. At the start of the study, each otherwise healthy subject was randomly assigned to either the placebo group or the low dose (100 mg) aspirin group.

Despite many observational studies linking aspirin use to lower cancer rates, the ASPREE trial is unexpected No such correlation found. Almost all metrics showed little difference between placebo and aspirin. In fact, the Aspirin group surprisingly has slightly higher all-cause mortality and cancer-related mortality. More unusually, the ASPREE trial reported more deaths from colorectal cancer than the placebo group.

Professor Andrew Chan of Harvard School of Medicine shows that the discrepancies in the results of the ASPREE clinical trial compared to this new meta-analysis reduce aspirin’s risk of developing cancer only if it begins at a younger age. It is possible that

“These results are different from those in the ASPREE trial. The ASPREE trial did not appear to be associated with a reduced risk of cancer, even suggesting that cancer may cause increased mortality,” Chan says. As mentioned in the email to Atlas. “This could be due to the fact that ASPREE only investigated the onset of aspirin in the elderly. The differential effects of aspirin when started later in life needed further investigation.”

Finally, Chan suggests that low-dose aspirin may be a reasonable cancer risk reduction option if initiated between the ages of 50 and 60. However, it states that this step should only be taken after discussing the risks and benefits with the doctor.

Mark Nelson of the University of Tasmania is working on the ASPREE project and says the data from his team’s clinical trials is much more reliable than observational studies, even when they are integrated into a meta-analysis.

“This is a meta-analysis of observational studies and is therefore subject to residual confounding,” Nelson commented on the new study. “Large prospective clinical trials with adjudicated cancer outcomes such as ASPREE are more rigorous and therefore reliable in providing evidence of harm and benefit.”

Nelson provides a clear and concise answer when asked if there is a background for healthy people to take aspirin as a preventative drug.

“No,” he says.

Carlo La Vecchia, senior author of a new meta-analysis at the University of Milan, says this study seems to point to the beneficial effects of aspirin in the prevention of some cancers, but many factors to consider in advance. Those who are suggesting that there is begin to take the drug. There is no broad general recommendation that applies to everyone because every individual has his or her own subjective set of risk factors.

“Taking aspirin to prevent bowel cancer and other cancers should only be done in consultation with a doctor who can consider the person’s personal risk,” La Vecchia said. “This includes sex, age, family history of first-degree relatives of the disease, and other risk factors. Those at high risk of disease are most likely to benefit the most from aspirin.”

New research published in journal Oncology records.

Source: European Society of Medical Oncology