A new American study says that women who take low to moderate doses of aspirin every day have a reduced risk of dying from any cause, but especially from heart-related illness.
The study is published in the Archives of Internal Medicine and was led by Dr Andrew T Chan, assistant professor of medicine at Harvard Medical School in Boston.
Previous studies have suggested that women who take regular doses of aspirin have a lower risk of dying from heart disease and cancer, but none has yet suggested that the drug confers an overall reduced death risk.
This study used records of nearly 80,000 female nurses from the Nurses’ Health Study who were followed for 20 years from 1976 and did not have cardiovascular disease or cancer at the start.
The women were contacted every 2 years and asked if they were taking aspirin and if so how many tablets per week at what dosage. Other data that was available were ways to assess cardiac risk factors, such as family history and general health data.
The study found that:
— 45,305 women did not use aspirin,
— 29,132 took 1 to 14 standard 325 mg tablets a week (low to moderate dose), and
— 5,002 took more than 14 tablets (high dose).
By the start of June 2004:
— 9,477 of the women had died, and this figure included 1,991 deaths from heart disease and 4,469 from cancer.
Compared to women who said they did not take aspirin, the women who had said they took aspirin regularly had a:
— 25 per cent lower risk of death from any cause,
— 38 per cent lower risk of death from cardiovascular disease, and
— 12 per cent lower risk of death from cancer.
It took only five years of aspirin use for the reductions in cardiovascular death risk to show, said the researchers. However, in comparison, “a significant reduction in risk of cancer deaths was not observed until after 10 years of aspirin use”, they said.
The lower death risk benefit from aspirin use was confined to low and moderate doses only and was greater in older women and those who had more cardiac risk factors.
The authors say their findings suggest further investigations should be done to explore the potential benefits of aspirin for the prevention of chronic diseases.
There are those who find these results surprising and debatable. In an accompanying editorial, Dr John A Baron, of Dartmouth Medical School, in Lebanon, New Hampshire, says these findings are quite different to those of many other studies into the use of aspirin by healthy women.
He refers to another large piece of research, the Women’s Health Study, that tracked 40,000 women for 11 years that failed to find any link between aspirin use and death risk from cardiovascular or any other cause.
Dr Baron asks, “”Is aspirin really that good or is there some other explanation for the findings that differ so much from those of the WHS and other primary prevention trials?”
He adds “The difference between the NHS study and the aggregated data from the WHS and other trials is too large to be explained by potential weaknesses in the randomized studies. At the same time, one has to consider that the observational NHS may not have been able to deal with the differences between aspirin users and non-users”.
He concludes, therfore that “these new findings by Chan et al cannot overcome the accumulated evidence that aspirin is not particularly effective for the primary prevention of death from cardiovascular disease in women”.
The study was not a randomized controlled trial, but an observational one that compares self-determined subgroups within the overall sample. Therefore it would be wrong to advise women to start taking aspirin based on these results. Also, because aspirin has potentially serious side-effects such as stomach bleeding no-one should take the decision to take aspirin every day without consulting their doctor.
“Long-term Aspirin Use and Mortality in Women.”
Andrew T. Chan, JoAnn E. Manson, Diane Feskanich, Meir J. Stampfer, Graham A. Colditz, Charles S. Fuchs.
Arch Intern Med. 2007;167:562-572.
Vol. 167 No. 6, March 26, 2007
Click here for the Aspirin Foundation (site supported by drug companies).
Written by: Catharine Paddock
Writer: Medical News Today