Optimizing diagnosis of Transient Ischemic Attack

Abstract

A Transient Ischemic Attack (TIA) is an important warning sign that a patient is at risk of a full stroke in the near future. Timely diagnosis and initiation of stroke preventive treatment, most notably the start of antiplatelet therapy, drastically reduces the early risk of stroke. However, the clinical diagnosis of TIA can be notoriously difficult. This thesis focused on (i) the value of tests or tools to support the clinical diagnosis of TIA, in particular blood biomarkers and clinical prediction models, and (ii) delay in the diagnosis and treatment of TIA, notably patient delay and its determinants. A systematic review on patient delay showed that more than a third of TIA patients delay seeking medical attention for more than 24 hours. Our own cohort study demonstrated that there is also considerable physician delay. Awareness among GPs about the importance of a rapid start of antiplatelet therapy in suspected TIA should be improved. Our study “Markers in the Diagnosis of TIA (MIND-TIA)” showed that currently available blood biomarkers have no additional value in the diagnosis of TIA. We used the MIND-TIA cohort also for validation of the recently proposed “Explicit Diagnostic Criteria for TIA (EDCT)”. The EDCT had good overall accuracy and especially high negative predictive value, and may be a useful tool for GPs to support the clinical diagnosis of TIA. The results of the panel diagnosis in MIND-TIA indicated that overdiagnosis of TIA, and thus overtreatment, are common.