Relative Survival After Transient Ischaemic Attack

Abstract

There is a lack of modern-day data quantifying the effect of transient ischemic attack (TIA) on survival, and recent data do not take into account expected survival. Data for 22 157 adults hospitalized with a TIA from July 1, 2000, to June 30, 2007, in New South Wales, Australia, were linked with registered deaths to June 30, 2009. We estimated survival relative to the age- and sex-matched general population up to 9-years after hospitalization for TIA comparing relative risk of excess death between selected subgroups. At 1 year, 91.5% of hospitalized patients with TIA survived compared with 95.0% expected survival in the general population. After 5 years, observed survival was 13.2% lower than expected in relative terms. By 9 years, observed survival was 20% lower than expected. Females had higher relative survival than males (relative risk, 0.79; 95% CI, 0.69-0.90; P<0.001). Increasing age was associated with an increasing risk of excess death compared with the age-matched population. Prior hospitalization for stroke (relative risk, 2.63; 95% CI, 1.98-3.49) but not TIA (relative risk, 1.42; 95% CI, 0.86-2.35) significantly increased the risk of excess death. Of all risk factors assessed, congestive heart failure, atrial fibrillation, and prior hospitalization for stroke most strongly impacted survival. This study is the first to quantify the long-term effect of hospitalized TIA on relative survival according to age, sex, and medical history. TIA reduces survival by 4% in the first year and by 20% within 9 years. TIA has a minimal effect on mortality in patients <50 years but heralds significant reduction in life expectancy in those >65 years.