Taking a daily dose of aspirin can dramatically reduce the risk of developing and dying from cancer, especially from tumours of the gastrointestinal tract, researchers from Queen Mary University of London have found.
To reap the benefits, said the study, patients needed to take a 75-100 mg daily dose for at least five years, and preferably for 10 years, between the ages of 50 and 65. No benefit was seen while taking aspirin for the first three years, but an effect was then seen on incidence. Death rates reduced only after five years, and most of the benefits were seen after patients had taken aspirin over a prolonged period and then stopped.
The researchers collated the most recent systematic reviews from 51 clinical trials of the effect of aspirin on the incidence of and mortality from specific cancers and cardiovascular events.
The results, published in the Annals of Oncology, showed that aspirin could reduce incidence and mortality from gastrointestinal cancers by around a third. The effect was most pronounced in colorectal cancer, where it reduced incidence by 35% and mortality by 40%. In oesophageal cancer, incidence was reduced by 30% and mortality by 50%, and in gastric cancer these decreased by 30% and 35%, respectively.
The study also found strong evidence of a smaller effect on some other cancers. Aspirin reduced the incidence of lung cancer by around 5% and mortality by 15%, in prostate cancer incidence fell by 10% and mortality by 15%, and in breast cancer incidence reduced by 10% and mortality by 5%.
The study also showed that aspirin had a preventive effect on myocardial infarction: it reduced incidence by 18% and mortality by 5%.
The effect of aspirin on strokes was more complex: its use adversely affected haemorrhagic strokes but was beneficial for ischaemic strokes with a 5% net reduction.
Daily aspirin reduces risk of developing and dying from cancer, researchers find | The BMJ.