| Transient ischemic attack (TIA)is a recurrent and transient neurological impairment of focal cerebral caused by regional dysaemia. the most important clinical features of Ischemic attack are the temporal, regional and recurrent, and so it have been considered to be "innocent" .In recent years, with the development of clinical research and accumulation of clinical cases, it was found that 50% patients of stroke are accompanied by transient ischemic attack (TIA)history and a proportion of people with TIA will develop a cerebral infarction. If we do not pay more attention to the TIA attack, it will bring calamity and financial burden to the patients' life. Therefore, a reasonable assessment, prognosis of short-term stroke and appropriate treatment of patients after TIA are necessary.At present, lots of studies about prognostic factors of TIA have already been published in our country. The lack of a large sample, multi-center follow-up data and scientific methods of statistical analysis make the results unreliable. Therefore, we do not have an effective and distinguished model forecast the possibility of stroke after TIA till now.Since 2000, Johnston and Rothwell do lots of observations, follow-up tracking and analysis to Outpatients and inpatients on short-term stroke factors after TIA (including population characteristics, drug history, treatment, TIA features and examination). Then they quantify these factors according to their significance and form models of California, ABCD and ABCD2 successfully, which can forecast the possibility of stroke after TIA correctly. ABCD2 scores is the most advanced model comparing to the others, which was announced before long. However, the scores'reliability and validity still need to be verified by different cohorts of patients.To validating the prognostic scores, we chose 89 patients with TIA (carotid artery system)form№.3 Hospital of Jilin University as validation cohort. We sent these patients to different groups according to their prognostic socres, and observe their 2days, 7days rate of stroke, and compare the difference of each group. Then we assess the predictive value of each risk factor in the score and analysis their predictive power relative to 7days risk of stroke. At last, we make treatment efficacy analysis about 4 therapies on patients in moderate and high risk group.Through observation and analysis, we got the 2days risk of stroke in TIA patients: low-risk group(score0～3, risk0%), moderate-risk group(score4～5, risk7%), high-risk group(score6～7, risk14%). The 7days risk of stroke is 5% in low-risk group, 22% in moderate-risk group, 29% in high-risk group. Statistical comparisons were performed between subgroups of patients using theχ2 test. There is P>0.05 in the 2days-risk stroke groups. It shows that the predictive value of the scores for 2days risk of stroke is not significant. The statistical significance of 7days risk of stroke is P≤0.05. So the ABCD2 scores can identify hospitalized TIA patients with a high risk of early stroke in 7days. The predictive value in identifying risk of stroke in 2days is lack of statistical significance, which is still needed to be further studied.We classified hospitalized TIA patients into 3 groups according to prognostic scores in 7days subsequently. In order to assessing the predictive value of ABCD2 score in identifying patients in high risk of stroke in 7days, we plot receiver operating characteristic curve (risk stratification). Our finding is that the area under the curve is 0.689 [95% CI, 0.545 to 0.834, P<0.05.]. Sensitivities and specificities of prediction were determined at each cut-off of the score. Score4 (sensitivity, specificity)= (0.846, 0.513), score6 = (0.154, 0.934).Therefore, we could regard the operating point (4)as a pre-admission screening indicator. In details, if the prognostic score of TIA patients is range 0 to 3, they could be observed in outpatient department. On the other hand, if the score is higher than 4, they must be admitted and treated. The specificity of operating point (6)is up to 0.934, it can be seen as a warning signal for a highly 7days early risk of stroke. So the ABCD2 score is a practical tool which is able to identify individuals at high early risk (7days)for stroke after TIA.We validate predictive factors in ABCD2 score relative to stroke in the logistic regression analysis. The results show that clinical features (motor weakness and speech disturbance)and duration of symptoms≥10mins are highly related with stroke after TIA (P≤0.05). They were selected into the regression equation. The best classification capacity of the equation is 85%,χ2 = 14.574, P = 0.001. When we apply ABCD2 scores in clinics to predict stroke after TIA, the clinical features and duration of symptoms should be considered in the first place. Other factors such as diabetes followed. The ABCD2 score may distinguish neurological symptoms due to seizure, migraine, or syncope from those due to focal brain ischemia, and identify patients more likely to have had a true TIA.Finally, we assess the curative effect of Ozagrel, traditional Chinese drug, Batroxobin and low-molecular-weight heparin in 46 patients, who were classified as moderate and high risk group and putted into 4 groups. We compare with the rate of 7days stroke after TIA to assess the curative effect of four types of treatment subsequently. Our funding is that there is no statistical significance(P>0.05)in the prevention of 7days stroke after TIA between 4 groups. The choice of Batroxobin or low-molecular-weight heparin may be based on which disturbance TIA patients were accompanied with, such as atrial fibrillation or hyperfibrinogenemia. In addition, the acceptance of patients should also be considered.In the summary, this score, termed ABCD2, was a more accurate predictor than either of the previous scores in the two derivation groups and generally performed better in the validation cohorts. Our group validated the predictive value of the ABCD2 score in a cohort of TIA inpatients of our hospital in 7days. Moreover, we can regard the operating point (4)as a pre-admission screening and operating point (6)as a strong early warning signal for 7days risk of stroke. So as to remind clinicians that the stroke will occur subsequently. In this way, we can make early detection, prevention and treatment to the patients with highly early risk of stroke after TIA. The basis of treatment of TIA is composed of anti-platelet aggregation and promoting blood flow .The choice of defibrase or anticoagulant drugs may not decrease the possibility of 7days stroke. In addition, we also found that the clinical features and duration of symptoms of ABCD2 score are of greater prognostic value, which may help clinicians identify patients more likely to have had a true TIA. In view of the imperfect prediction of the score, further research on imaging and other potential biomarkers is justified.
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