A transient ischemic attack (TIA) isn’t just a harbinger of stroke. New research shows that TIAs, which often are called ministrokes, can cut life expectancy by up to 20%.
The study, published online today in Stroke: Journal of the American Heart Association, is the first to examine life expectancy in people who have had a TIA compared with expected mortality rates from all causes of death in the general population. An estimated 240 000 TIAs occurred in the United States in 2002. Studies show that about 15% of strokes are preceded by a TIA.
Researchers in Australia tracked medical records of 22 157 adults who were hospitalized with a TIA in New South Wales between July 2000 and June 2007. Median follow-up time was 4.1 years. The investigators then compared the patients’ records with death registry data for the region through June 2009.
Investigators found that a year after having a TIA, 91.5% of the patients were still living compared with a 95% life expectancy in the general population. After 5 years, 67.2% of patients were still alive compared with expected survival of 77.4% in the general public. At the 9-year mark, patients’ survival was 20% lower than expected.
The study is “a welcome contribution,” said James R. Brorson, MD, associate professor of neurology at the University of Chicago, who was not involved in the research. Brorson said the data can help physicians advise patients “about the seriousness of TIA as a marker for serious vascular risk and heightened risk of mortality.”
Researchers noted that older patients were the most vulnerable. Compared with those younger than 50 years, patients aged 50 to 64 years had nearly twice the likelihood of higher-than-expected death rates. The risk of reduced survival was nearly 5 times higher in patients aged 65 to 74 years and 11.02 times higher in patients aged 85 years and older.
“We thought the reverse might be true,” said lead author Melina Gattellari, PhD, of the University of New South Wales in Sydney, in a statement. Gattellari said she and her colleagues thought it likely that older patients’ survival wouldn’t be affected very much by TIAs because they often have other chronic conditions with a greater impact on health.
“Even a distant history of TIA is a major determinant of prognosis,” she said. “The risks faced by TIA patients go well beyond their early stroke risk.”