Should healthy middle-aged people take daily aspirin ?

Studies have shown that aspirin, a commonly used painkiller, is linked to reductions in heart attacks and strokes, but it can irirtate the stomach and cause serious internal bleeding particularly in elderly people.

According to a new Oxford Univeristy study, published in The Lancet last week, taking a daily low dose of aspirin for reduced cancer deaths during and after the trials and the benefit increased with duration of treatment.

The researchers examined the data of 8 trials that looked at the effects of daily dose of aspirin on preventing heart attacks involving over 25,000 people. They found that aspirin reduced cancer deaths by 20% during the trial, but after 5 years, death rates were 34% lower for all cancer deaths. They also found the risk of all cancer deaths over a period of 20 years remained 20% lower for those who had taken aspirin, about 40% for bowel cancer, 30% for lung cancer, 10% for prostate cancer and 60% for oesophageal cancer. But there were not enough women participants to determine if daily aspirin could reduce breast, ovarian or endometrial cancer deaths.

The lead researcher said this study confirms the results of the previous study that found aspirin has preventive effect against cancer and has demonstrated a major new benefit of the drug. He believes that the findings have implications for guidelines on use of aspirin and the most benefit would be seen for those start taking aspirin between the age of 40 - 50 and continue for 25 years.

The previous study by the same authors, also published in The Lancet in October 2010, showed that a low dose of aspirin, 75mg per day taken for several years, reduced deaths due to colorectal cancer. However, opinions were divided on the result of the study.

Some said that the study did not give a balanced view of the effect of the treatment because it did not report the potential harms. The protective effects against cardiovascular disease were thought to be small for healthy adults. Some advised that aspirin should not be used to prevent heart attacks and strokes in "healthy" people as the risks outweigh potential benefits. Others said more research is needed before recommending taking aspirin to reduce cancer deaths.

Source: Rothwell PM, Fowkes FGR, Belch JFF, et al. Effect of daily aspirin on long-term risk of death due to cancer: analysis of individual patient data from randomised trials. The Lancet. 2010 Jan 7. [Epub ahead of print] Online publication 7 December 2010 ( f/t via Athens)

Previous studies :

Rothwell PM, Wilson M, Elwin C-E et al. Long-term effect of aspirin on colorectal cancer incidence and mortality: 20-year follow-up of five randomised trials. The Lancet 2010, Early Online Publication, October 22 (f/t via Athens)

Benamouzig R, Uz B. Aspirin to prevent colorectal cancer: time to act? The Lancet 20110, Early Online Publication, 22 October (f/t via Athens)

Should aspirin be used for migraine relief?

A new Cochrane systematic review found that high dose aspirin can reduce migraine headache within 2 hours.


The review compared the use of aspirin to placebo or other migraine drugs including 13 studies and 4222 patients with migraine attacks. The amount of aspirin used in these studies varied between 900 - 1000 mg. Patients were randomly assigned to either a single dose of aspirin or a placebo or an active drug.

Researchers found that 24% of aspirin users were pain-free within 2 hours comapred to 11% of placebo users, aspirin also reduced the symptoms of nausea and vomiting, but aspirin plus antiemetic reduced these symptoms significantly compared with placebo. They concluded that 1000 mg of aspirin is effective for migraine relief, similar to the effect with sumatriptan.


Critics say that it is important to note that the over-the-counter standard aspirin is only 75mg and evidence has shown that regular use of aspirin may increase stomach problem or bleeding, taking high dose aspirin may increase these side effects. Also the effectiveness of aspirin may not apply to everyone as only a quarter of patients in these studies were pain-free after 2 hours.


Source : Kirthi V, Derry S, Moore RA, McQuay HJ. "Aspirin with or without an antiemetic for acute migraine headaches in adults (Review)". The Cochrane Library 2010, Issue 4

Can aspirin reduce breast cancer recurrence?

According to a new study published online in the Journal of Clinical Oncology, there was an association between frequent use of aspirin and lower risk of dying from cancer.

Researchers used survey data from US Nurses' Health Study to examine the effect of aspirin on breast cancer recurrence and survival including over 4000 nurses between 1980 and 2006. They found that women who took aspirin after finishing breast cancer treatment were half as likely to die from the disease compared with those who did not use aspirin regularly. However, the researchers pointed out that the participants were all nurses, the results may not be applied to the general population and they called for a randomised controlled trial to establish whether aspirin really caused the reduced risks they had found.

Previous studies on aspirin's anticancer effects have come to mixed conclusions, experts warned that patients should not start taking aspirin as there are risks associated with taking aspirin including bleeding and gastrointestinal complications.

Source: Holmes MD, Chen WY, Li L, et al. "Aspirin Intake and Survival After Breast Cancer". Journal of Clinical Oncology 2010 ( f/t via Athens)

Should healthy people use low-dose aspirin routinely?

Low-dose aspirin is widely used as secondary prevention of cardiovascular disease in people who have had heart attacks or stroke. The latest issue of the Drug and Therapeutics Bulletin (DTB) examined whether healthy people who have not had cardiovascular events should use low-dose aspirin as primary prevention.


The DTB study is not a systematic review but looked at current research evidence and expert opinion. It pointed out that although aspirin is not specifically licensed for use as primary prevention in the UK, various guidelines including NICE and SIGN recommend aspirin for primary prevention in certain groups of people such as those with type 2 diabetes and high blood pressure.


However, DTB found that current evidence does not support routine use of low-dose aspirin in these groups due to the potential risk of serious bleeds and its low effect on death rates. It says "it is hard to recommend starting aspirin for primary prevention" and concludes that "... low -dose aspirin prophylaxis should not be routinely used for primary prevention."


Source: "Aspirin for primary prevention of cardiovascular disease?" Drug and Therapeutics Bulletin 2009;47:122-125 (Relevant BNF section: 2.9)

Doubts over aspirin use in diabetes

UK guidelines recommend a daily dose of aspirin as a "preventive" treatment in the diabetics as they are at a much higher risk of cardiovascular disease. However, a study published in the BMJ found no benefit from either aspirin or antioxodants in preventing heart attacks. It also increases the risk of internal bleeding.

The study invloved 1,276 adult patients with diabetes mellitus from 16 diabetic clinics in Scotland between November 1997 and July 2001. Participants were randomly assigned in four groups to receive the aspirin tablet + antioxidant capsule, or aspirin tablet + placebo capsule, or placebo tablet + antioxidant capsule or both a placebo tablet and a placebo capsule.

The findings show that in adults with diabetes and no symptoms of cardiovascular disease, there was no evidence that aspirin or antioxidants use prevented heart attacks, strokes, amputations or death. However, the drug was beneficial in people who already have a history of heart attack or stroke.

Experts said the study was "extremely important" because it confirms the concerns of aspirin use by the general population and it is worth revisiting the guidelines.

Source: Belch J, MacCuish A, Campbell I, et al. The prevention of progression of arterial disease and diabetes (POPADAD) trial: factorial randomised placebo controlled trial of aspirin and antioxidants in patients with diabetes and asymptomatic peripheral arterial disease. BMJ 2008; Published 16 October ( f/t via Athens)

Aspirin can cut asthma in women

The Telegraph reported a study that found aspirin could cut the risk of asthma in women by 10%.

The study was based on a randomised controlled trial involving 37,270 female health professionals who took either 100 mg of aspirin every other day or a placebo. The participants completed questionnaires over a 10 year period, which included a question relating to newly diagnosed asthma. The results showed a 10% fewer cases of asthma with aspirin use. The researchers said that the results might not apply to all women.

Source: "Randomised Aspirin Assignment And Risk Of Adult-Onset Asthma In The Women's Health Study". Thorax 2008 March 13 (epub ahead of print)

Aspirin resistant may increase heart attack risk

Aspirin is widely used to prevent heart attacks, strokes and blood clot, but the Telegraph reported that a review of 20 studies involving 3000 patients has found 28% do not respond to aspirin and there is no standard test to establish who are resistant to the drug.



The author concluded that "patients who are resistant to aspirin are at a greater risk of clinically important cardiovascular morbidity long term than patients who are sensitive to aspirin" and called for further research. The report was published in the BMJ.



Source: Aspirin "resistance" and risk of cardiovascular morbidity: systematic review and meta-analysis BMJ, doi:10.1136/bmj.39430.529549.BE (published 17 January 2008)

Current evidence does not support aspirin therapy in IVF

Previous studies on the use of aspirin have shown conflicting evidence whether low-dose aspirin is beneficial in IVF.


According to a systematic review of 9 studies in different parts of the world involving more than 1400 women undergoing IVF or ICSI ( intracytoplasmic sperm injection) to treat infertility, currently available evidence does not support the use of aspirin in IVF or ICSI treatment. Further research into this treatment is needed.


Source: "Low-dose aspirin for in vitro fertilisation". Cochrane Database of Systematic Reviews 2007, Issue 4

Aspirin - men's drug?

Aspirin has been linked to many health benefits, but a study which analysed 23 previously published clinical trials for the effect of aspirin in heart attack prevention, involving more than 113,000 patients found that women may be less responsive to aspirin than men for heart protection.


The researchers believe that gender may be one of the main influences on aspirin's protective powers. One UK expert said the finding is "potentially misleading" and that "taking aspirin in the months and years after a heart attack delivered equal benefits to men and women".


Source: "The influence of gender on the effects of aspirin in preventing myocardial infarction"
BMC Medicine 2007, 5:29 ( This is an open access journal article with full text )