Incidence and Predictors of Acute Ischemic Lesions on Brain Magnetic Resonance Imaging in Patients With a Clinical Diagnosis of Transient Ischemic Attack in China

Background: The associations between the clinical characteristics and diffusion-weighted imaging (DWI) positivity in patients with a clinical diagnosis of transient ischemic attack (TIA) are still poorly understood. The purpose of our study was to determine the incidence of TIA related acute infarction by DWI, and to determine the underlying predictors of DWI positivity in TIA patients.

Methods: Between Jan 2017 and Dec 2018, we retrospectively enrolled 430 patients with a clinical diagnosis of TIA who underwent DWI. Patients were divided into those with acute ischemic lesions (DWI positive group) and those without (DWI negative group). The clinical characteristics, laboratory data, and imaging parameters were compared between the two groups.

Results: A total of 430 time-based TIA patients (mean age, 61.4 ± 13.0) were enrolled in this study. About 126 (29.3%) of TIA patients had a DWI positive lesion in our series. Comparing TIA patients with positive DWI to those with negative DWI, acute lesions were more likely to be more male, have higher hyperlipidemia and a smoking history, more speech abnormalities and increased motor weakness; and higher systolic and diastolic blood pressure, homocysteine, fasting blood glucose, and the scores of ABCD2, ABCD3, ABCD3-I, and Dawson. Several independent predictors of DWI positivity were identified with logistic regression analysis: motor weakness (odds ratio 4.861, P = 0.021), speech abnormalities (odds ratio 4.029, P = 0.024), and ABCD3-I (odds ratio 13.141, P = 0.001). ABCD3-I showed the greatest area under the ROC curve, with a sensitivity of 85.7% and specificity of 72.4%.

Conclusion: In patients with a clinical diagnosis of TIA, 29.3% demonstrated acute DWI lesions on brain magnetic resonance imaging (MRI). They were associated with motor weakness, speech abnormalities and higher ABCD3-I score at admission.

Dual antiplatelet therapy reduced stroke risk in high-risk patients with transient ischaemic attack assessed by ABCD3-I score

BACKGROUND AND PURPOSE

Several clinical trials have demonstrated that dual antiplatelet therapy (DAPT) benefited patients with transient ischaemic attack (TIA) with an ABCD2 score ≥4. The present study aimed to investigate whether the ABCD3-I score could be a more appropriate tool for selection of patients with TIA to receive DAPT in real-world settings.

METHODS

We derived data from the TIA database of The First Affiliated Hospital of Zhengzhou University. The predictive outcome was ischaemic stroke at 90 days. The additive interaction effect was presented by the attributable proportion due to interaction. Kaplan-Meier curves were plotted to present cumulative stroke rates in different risk categories with monotherapy and DAPT. Cox proportional hazards regression was used to determine risk factors associated with stroke.

RESULTS

Among 785 patients, the mean (SD) age was 56.95 (12.73) years and 77 patients (9.8%) had an ischaemic stroke at 90 days. A total of 55.8% of patients (attributable proportion due to interaction; 95% confidence interval, 20.8%-90.9%) were attributed to additive interaction of ABCD3-I score and antiplatelet therapy. Kaplan-Meier curves showed a significant difference between patients receiving monotherapy and DAPT in high-risk patients with TIA (P = 0.021). DAPT reduced 90-day stroke risk in high-risk patients with TIA as assessed independently by ABCD3-I score (adjusted hazard ratio, 0.43; 95% confidence interval, 0.20-0.92, P = 0.031). The benefit did not exist in low- and medium-risk patients by ABCD3-I score (patients with ABCD2 score ≥ 4 or <4).

CONCLUSIONS

High-risk patients with TIA assessed by ABCD3-I score received the most pronounced clinical benefit from early use of DAPT in real-world clinical experience.