Neurology：DWI病灶阳性的短暂性脑缺血发作患者卒中风险增加

短暂性脑缺血发作（TIA）是脑卒中最重要的危险因素，但TIA症状持续时间及DWI病灶与脑卒中的关系尚不清楚，来自德国的Mohamed Al-Khaled等医生在一项人群队列研究中评估了不同症状持续时间的短暂性脑缺血患者磁共振弥散加权序列确定的的急性梗塞频率及卒中风险，发表在2013年5月21日的Neurology杂志上，研究显示：对于不同症状持续时间的短暂性脑缺血发作的患者来说，MRI-DWI病灶阳性患者性比阴性病灶患者卒中风险增加。

在54个月的随访期内（从2007年11月开始），共有来自15家医院的3724例患者（平均年龄为67 ± 14岁，其中45%为女性）纳入研究，这些患者的短暂性神经症状均小于24小时。所有患者在住院期间均进行磁共振弥散加权序列（DWI-MRI）检查。

在3724例患者中，1166例显示有急性梗塞（占32.2%; 95%可信区间[CI]为30.8%–33.8%），在平均7天的住院期间内88例患者发生卒中（占2.4%; 95% CI为1.9%–2.9%）。DWI病灶阳性相比阴性的TIA患者的卒中风险明显增高(分别为4.5%和1.5%，p < 0.001)。Logistic回归分析显示卒中风险与DWI病灶阳性(优势比[OR]为3.1; 95% CI, 2.0–4.8; p < 0.001)，房颤(OR, 2.1; 95% CI, 1.3–3.5; p = 0.001)，症状持续时间小于1小时(OR, 1.5; 95% CI, 1.0–2.4; p = 0.042)相关。症状持续时间小于1小时与症状超过1小时的患者相比发生急性梗塞的比例较低(分别为24%和36%,p < 0.001)，然而两组的卒中风险无明显差异(分别为2.8%，2.1%， p = 0.22)。不管在症状持续时间小于1小时(5.2%比2.0%, ，p = 0.002)还是症状持续时间大于1小时(4.1%比1.1%, p < 0.001)，DWI病灶阳性的患者与病灶阴性患者相比卒中风险都增加。

对于不同症状持续时间的短暂性脑缺血发作的患者来说，MRI-DWI病灶阳性患者性比阴性病灶患者卒中风险增加。

MRI findings and stroke risk in TIA patients with different symptom durations.
OBJECTIVE
To determine the frequency of acute infarction detected by diffusion-weighted imaging (DWI)-MRI and stroke risk in TIA patients with different symptom duration in a population-based study.
METHODS
During a 54-month period (starting November 2007), 3,724 admitted patients (mean age, 67 ± 14 years; 45% women) with transient neurologic symptoms lasting <24 hours from 15 hospitals were included. All patients underwent DWI-MRI during hospitalization.
RESULTS
Of 3,724 patients, 1,166 showed an acute infarction (32.2%; 95% confidence interval [CI], 30.8%-33.8%) and 88 (2.4%; 95% CI, 1.9%-2.9%) had a stroke during hospitalization (7 days). Stroke risk was higher in patients with tissue-positive DWI than in those with tissue-negative DWI (4.5% vs 1.5%, respectively; p < 0.001). Logistic regression analysis revealed that stroke risk was correlated with positive DWI (odds ratio [OR], 3.1; 95% CI, 2.0-4.8; p < 0.001), atrial fibrillation (OR, 2.1; 95% CI, 1.3-3.5; p = 0.001), and symptom duration <1 hour (OR, 1.5; 95% CI, 1.0-2.4; p = 0.042). Patients with symptoms lasting <1 hour had a lower rate of acute infarction than those with symptoms lasting ≥1 hour (24% vs 36%, respectively; p < 0.001), whereas stroke risk did not differ between the groups (2.8% vs 2.1%, respectively; p = 0.22). Stroke risk was higher after tissue-positive events than tissue-negative ones in patients with symptom duration <1 hour (5.2% vs 2.0%, respectively; p = 0.002) and in those with symptom duration ≥1 hour (4.1% vs 1.1%, respectively; p < 0.001).
CONCLUSION
Stroke risk was higher after tissue-positive events than tissue-negative ones in TIA patients with different symptom duration.