Scientists develop new tool to measure aspirin risk for cardiovascular disease

There’s a lot of debate around the effectiveness of aspirin in the medical world. Some studies claim it does wonders for health, while others cast doubt over its ability to prevent illness.

Now though, Auckland researchers have developed a new tool that could make aspirin a safer and better-targeted preventative for heart disease and stroke.

An aspirin a day may prevent cardiovascular disease (CVD), but not without potentially serious risks of internal bleeding. The risk of bleeding varies from person to person, and until now, doctors had no objective way of assessing an individual patient’s risk.

A team of researchers from the University of Auckland and Middlemore Hospital have developed bleeding risk models for women and men which provide a personalised estimate of a patient’s risk of a major bleed. The researchers published their findings in the journal Annals of Internal Medicine.

The study’s lead author Dr Vanessa Selak said it was mostly aimed at those who had not had a heart attack or stroke, but were at high risk and thinking about using aspirin.

“For people who have already had a heart attack or stroke, the benefit of aspirin in reducing CVD generally outweighs its harms in increasing bleeding. However, guidelines are unclear in people who are at high risk of having their first heart attack or stroke,” she said.

“There is a lot of confusion about who should take it, so it is likely that some people are receiving aspirin when they shouldn’t be and others are not receiving it when they could potentially benefit from it.”

To identify the extra bleed risk from aspirin, the researchers worked out a baseline risk of major bleeds — those that resulted in hospitalisation or death — in people at high risk of CVD who were not already taking the drug.

They analysed data from more than 350,000 such people aged 30 to 79 who had seen their GP or practice nurse for a CVD risk assessment between 2002 and 2015. Researchers discovered this original pool of people went on to have 4,442 major bleeds, of which 313 were fatal.

Risk factors for both CVD and major bleeds included older age, smoking, diabetes, ethnicity, deprivation, and use of blood pressure-lowering medication. Other risk factors for bleeds that were not also risk factors for CVD included a history of cancer, bleeding, peptic ulcer disease or alcohol-related conditions, or the use of corticosteroids or SSRI antidepressants.

Selak said the next step was to develop a calculator for doctors to use with their patients. The aspirin benefit-harm calculator may be available by the end of the year.

“Our next step is to develop a calculator that integrates the benefits and harms of aspirin for prevention of CVD to make it easier for clinicians to work out, for a specific patient, whether the benefits of aspirin are likely to outweigh its harms,” Selak said.

It’s always important to discuss the benefits and potential side effects of aspirin with a GP or health professional before taking the medication.

What do you think of the latest findings? Do you take aspirin regularly?