Caution urged in routinely taking long-term asprin

Report discourages long-term, low doses despite British study claiming pill significantly cuts risk of getting cancer.

Asprin 311 AP (photo credit: AP)
Asprin 311 AP
(photo credit: AP)
Medical authorities around the world are warning the public not to take a daily mini-dose of aspirin without consulting first with their doctors, even though a British observational analysis showed that over five years, such a dose reduces the risk of various cancers by 10 percent to 60%.
The Health Ministry in Jerusalem did not issue a public advisory on the subject via all the health reporters, although it received a request to do so from The Jerusalem Post.
But it did tell the Post that even though aspirin is an easily purchased and cheap drug, “every medication has a consumer’s leaflet inside explaining possible side effects and dangers from its use. A doctor or pharmacist should be consulted before taking it long term even though it does not require a prescription.”
Aspirin, if taken in significant doses and if the individual suffers from certain conditions or has a specific genetic background, is toxic, can cause bleeding in the stomach in about one person per 1,000 and can even cause fatal hemorrhagic strokes.
The British study, which was conducted at the University of Oxford and appeared Tuesday in the British journal The Lancet, retrospectively studied eight separate trials encompassing 25,570 patients.
Dr. Peter Rothwell concluded that taking low doses of aspirin (75 milligrams or a “baby aspirin”) daily can reduce the risk of many kinds of cancer and that the evidence is strong enough to suggest that individuals over the age of 40 take it daily to help protect against cancers.
Rothwell claimed that while taking aspirin bears a small risk of hemorrhage, such a risk was “beginning to be drowned out” by its benefits in reducing the risk of cancers and reducing the risk of heart attacks.
Rothwell and his colleagues found that cancer deaths among those who took aspirin in low doses were 21 percent lower during the studies and 34 percent lower after five years. The painkilling and fever-reducing drug was shown to reduce the prevalence of esophageal cancer by 60%, gastrointestinal and colon cancers by half to two-fifths, lung cancer by a third and others by lower rates, according to Rothwell.
In the past, researchers have explained that aspirin blocks an enzyme that triggers inflammation and cell division. Rothwell said that higher doses were not more effective than low doses of aspirin.
Other experts cautioned that the study wasn’t persuasive enough to recommend a policy of daily low-dose aspirin for healthy people who reach middle age. They added that two-thirds of the patients were men, thus the study didn’t prove that aspirin could protect women and men equally.
Dr. Raymond DuBois, a cancer prevention specialist who is provost of the University of Texas M.D. Anderson Cancer Center, told newspapers abroad: “I definitely think we wouldn’t want to make any treatment decisions based on this study.”
He said that the studies on which the meta-analysis was based had been carried out to investigate risks of heart disease, so the patients “being compared may differ on things that affect cancer risk, such as family history of the disease.”
Critics also noted that several of the authors of the initial studies had been paid for work they did for pharmaceutical firms that manufacture aspirin.
Prof. Gad Rennert, head of the Israel Cancer Registry and an adviser to the Israel Cancer Association, said on Wednesday that “for several years, we have known that regular use of aspirin is connected with a decline in risk for various types of cancer.
Most of the evidence related to the risk of colon cancer being reduced when taking a high daily dose of 325 mg.”
Rennert added that studies began to appear showing that low-dose aspirin, which posed a lower risk of bleeding, could be protective as well.
“Our studies in Israel show clearly that low-dose aspirin is connected with a lower risk of colon cancer and breast cancer and maybe other organs,” he said.
Although Rennert hadn’t had time to read the article in The Lancet carefully, he said he was “not surprised” by the findings.
The study “justifies a discussion on the use of aspirin for the older general population – certainly not those under 50. I would be calmer if before a wholesale recommendation to the public, we could carry out genetic examinations to check sensitivity to aspirin and its side effects, but there is no such optimal test.”