DAILY use of aspirin to prevent blood clots in elderly patients over age 75 leads to an increased risk of serious or fatal internal bleeding, according to research published in the Lancet.
Around half of all adults 75 and over in the US and Europe take small daily doses of aspirin – ranging from 75 to 150 milligrams – or other clot-inhibiting drugs. Lifelong treatment with such medications is recommended for patients who have suffered a heart attack or stroke.
Previous research has established that even among people with no history of heart problems or stroke, the risk of gastrointestinal bleeding goes up with age for aspirin users – but clinical tests have mainly involved patients younger than 75 who had taken aspirin for only a couple years. How much the risk of bleeding might rise with age was largely unknown.
Peter Rothwell from the University of Oxford led a team of researchers in examining medical records for more than 3,000 patients who had had a stroke or heart attack, and taken daily aspirin or its equivalent for many years. Half the patients were 75 or older at the start of the period covered by the study.
Over the following decade, 314 patients were admitted to hospital for bleeding. Risk increased sharply with age: for patients under 65, the annual rate of hospital admissions due to bleeding was 1.5 per cent but for patients 75 to 84, the rate rose to 3.5 per cent. In patients over 85 the risk increased to 5 per cent. The chances that bleeding was disabling or fatal, while lower, increased in roughly the same proportions across the different age groups.
The researchers suggest that taking proton pump inhibitors (PPI) could reduce bleeding in the upper gastrointestinal tract by up to 90 per cent.
Said Rothwell: "We have known for some time that aspirin increases the risk of bleeding in elderly patients. But our study gives us a much clearer understanding of the size of the increased risk and the severity of the consequences.
"There is some evidence that long-term PPI use might have some small risks…the new data should provide reassurance that the benefits of PPI use at older age outweigh the risks."
Professor Helen Stokes-Lampard, Chair of the RCGP, commented: “The study does reassure us that in most cases, aspirin is still the most appropriate course of treatment for patients, but highlights the importance of managing its use carefully and effectively and that some patients may require additional medication to protect them.
"It’s helpful that the researchers suggest action to mitigate this risk - the prescription of a proton pump inhibitor (PPI) as a secondary drug - but this does raise a number of health implications. It will continue to be necessary to make decisions of a case by case basis, considering the patient’s unique circumstances and medical history, as well as the medications they are already taking and how they will interact with each other.”