Long-term survival and vascular event risk after transient ischaemic attack or minor ischaemic stroke: a cohort study

Abstract

Background: Determinants of survival and of risk of vascular events after transient ischaemic attack (TIA) or minor ischaemic stroke are not well defined in the long term. We aimed to restudy these risks in a prospective cohort of patients after TIA or minor ischaemic stroke (Rankin grade< or =3), after 10 years or more.

Methods: We assessed the survival status and occurrence of vascular events in 2473 participants of the Dutch TIA Trial (recruitment in 1986-89; arterial cause of cerebral ischaemia). We included 24 hospitals in the Netherlands that recruited at least 50 patients. Primary outcomes were all-cause mortality and the composite event of death from all vascular causes, non-fatal stroke, and non-fatal myocardial infarction. We assessed cumulative risks by Kaplan-Meier analysis and prognostic factors with Cox univariate and multivariate analysis.

Findings: Follow-up was complete in 2447 (99%) patients. After a mean follow-up of 10.1 years, 1489 (60%) patients had died and 1336 (54%) had had at least one vascular event. 10-year risk of death was 42.7% (95% CI 40.8-44.7). Age and sex-adjusted hazard ratios were 3.33 (2.97-3.73) for age over 65 years, 2.10 (1.79-2.48) for diabetes, 1.77 (1.45-2.15) for claudication, 1.94 (1.42-2.65) for previous peripheral vascular surgery, and 1.50 (1.31-1.71) for pathological Q waves on baseline electrocardiogram. 10-year risk of a vascular event was 44.1% (42.0-46.1). After falling in the first 3 years, yearly risk of a vascular event increased over time. Predictive factors for risk of vascular events were similar to those for risk of death.

Interpretation: Long-term secondary prevention in patients with cerebral ischaemia still has room for further improvement.