An Australian trial has shown daily aspirin does not lower the risk of death, disability or cardiovascular disease in healthy older people… but increases risk of major bleeding problems
However anybody who is taking aspirin should speak to their prescriber before ceasing the medication, says AMA president Dr Tony Bartone.
Three papers published in the New England Journal of Medicine have examined whether healthy older people without cardiovascular disease, dementia or physical disability who take low-dose aspirin can prevent ill health by doing so.
The Monash University-lead ASPREE (ASPirin in Reducing Events in the Elderly) trial, involving more than 19,000 patients in Australia and the US, found that one 100mg aspirin a day did not prolong life free of disability, and did not significantly reduce the risk of a first heart attack or stroke among healthy participants.
There was little difference in these measures between the 9589 patients in the placebo group and the 9525 in the aspirin group.
Instead, there was a slight increase in the incidence of serious bleeding: 3.8% in the aspirin group and 2.8% in the placebo group.
“After a median of 4.7 years of follow-up, the rate of cardiovascular disease was 10.7 events per 1000 person-years in the aspirin group and 11.3 events per 1000 person-years in the placebo group (hazard ratio, 0.95; 95% confidence interval [CI], 0.83 to 1.08),” the authors write in one of the ASPREE study papers, that focused on the effect on cardiovascular events and bleeding.
“The rate of major hemorrhage was 8.6 events per 1000 person-years and 6.2 events per 1000 person-years, respectively (hazard ratio, 1.38; 95% CI, 1.18 to 1.62; P<0.001).”
A second paper examining the effect of aspirin on all-cause mortality in the healthy elderly (70 years and older, or 65 and older for black and Hispanic Americans) reported that a total of 1052 deaths occurred during a median of 4.7 years of follow-up
“The risk of death from any cause was 12.7 events per 1000 person-years in the aspirin group and 11.1 events per 1000 person-years in the placebo group (hazard ratio, 1.14; 95% confidence interval [CI], 1.01 to 1.29),” the authors wrote.
“Cancer was the major contributor to the higher mortality in the aspirin group, accounting for 1.6 excess deaths per 1000 person-years.
“Cancer-related death occurred in 3.1% of the participants in the aspirin group and in 2.3% of those in the placebo group (hazard ratio, 1.31; 95% CI, 1.10 to 1.56).”
They said that while higher all-cause mortality was observed among apparently healthy older adults who received daily aspirin, than among those who received placebo, this was attributed primarily to cancer-related death and in the context of previous studies, this result was unexpected and should be interpreted with caution.
In terms of disability, “the rate of the composite of death, dementia, or persistent physical disability was 21.5 events per 1000 person-years in the aspirin group and 21.2 per 1000 person-years in the placebo group (hazard ratio, 1.01; 95% confidence interval [CI], 0.92 to 1.11; P=0.79),” the authors wrote.
“The rate of adherence to the assigned intervention was 62.1% in the aspirin group and 64.1% in the placebo group in the final year of trial participation.
“Differences between the aspirin group and the placebo group were not substantial with regard to the secondary individual end points of death from any cause (12.7 events per 1000 person-years in the aspirin group and 11.1 events per 1000 person-years in the placebo group), dementia, or persistent physical disability.”
According to principal investigator Professor John McNeil, head of Monash University’s Department of Epidemiology and Preventive Medicine, the results of the trial will result in a rethinking of global guidelines relating to the use of aspirin to prevent common conditions associated with ageing.
“Despite the fact that aspirin has been around for more than 100 years, we have not known whether healthy older people should take it as a preventive measure to keep them healthy for longer,” Professor McNeil said.
“Aspirin is the most widely used of all preventive drugs and an answer to this question is long overdue. ASPREE has provided this answer.
“These findings will help inform prescribing doctors who have long been uncertain about whether to recommend aspirin to healthy patients who do not have a clear medical reason for doing so.”
“ASPREE is a study that was probably long overdue,” he said.
“It has been obvious since the 1990s that there was a need for a trial of aspirin for primary prevention in people age 70 and over.
“But whereas funding for major trials typically comes from the pharmaceutical industry, aspirin is a drug that is off patent and is therefore a study that could only be done with public funds. It is to the great credit to the US NIH and the Australian NHMRC that they recognised this need and underwrote the substantial cost of undertaking a study of this magnitude.”
He said that the question of whether or not to prescribe aspirin to the healthy elderly is faced regularly by a typical GP. ASPREE was therefore directed at a question fundamental to their day to day practice.
“In the end the answer to the question can be boiled down to a simple proposition: ‘if you are elderly and don’t need it, don’t take it’.”
The researchers point out that ASPREE’s findings relate only to healthy older people, aged over 70 years, and do not apply to those taking aspirin on medical advice, for example those who have had a heart attack or stroke. They remind patients to consult their GP before changing their aspirin regime.
Dr Tony Bartone, national president of the AMA, spoke to Sky News’ Ashleigh Gillon on Monday and said that GPs are happy to discuss any patient concerns.
“We know that the evidence for the use of aspirin in those patients, who already had heart disease or other circulatory issues, they can actually prevent secondary issues, secondary episodes of either heart attacks or strokes happening in those patients,” he said.
“But here, this study has been looking at primary, so in terms of people previously well, and the evidence has come in and clearly shown that there is no benefit, and in fact, it can create secondary other issues which are obviously of concern.
“So, this is a welcomed study, but everybody who is currently taking aspirin should obviously see their GP before making changes to their regime.
“And we welcome all those inquiries into our consultation rooms today.”