dxy

 Discontinuing Prophylactic Transfusions Used to Prevent Stroke in Sickle Cell Disease

The Optimizing Primary Stroke Prevention in Sickle Cell Anemia (STOP 2) Trial Investigators
ABSTRACT

Background Prophylactic transfusion prevents strokes in children with sickle cell anemia who have abnormalities on transcranial Doppler ultrasonographic examination. However, it is not known how long transfusion should be continued in these children.

Methods We studied children with sickle cell disease who had a high risk of stroke on the basis of a transcranial Doppler screening examination and who had received transfusions for 30 months or longer, during which time the Doppler readings became normal. The children were randomly assigned to continued transfusion or no continued transfusion. Children with severe stenotic lesions on cerebral magnetic resonance angiography were excluded. The composite primary end point was stroke or reversion to a result on Doppler examination indicative of a high risk of stroke.

Results The study was stopped after 79 children of a planned enrollment of 100 underwent randomization. Among the 41 children in the transfusion-halted group, high-risk Doppler results developed in 14 and stroke in 2 others within a mean (±SD) of 4.5±2.6 months (range, 2.1 to 10.1) of the last transfusion. Neither of these events of the composite end point occurred in the 38 children who continued to receive transfusions. The average of the last two transcranial Doppler results before transfusion was started was the only predictor of the composite end point (P=0.05).

Conclusions Discontinuation of transfusion for the prevention of stroke in children with sickle cell disease results in a high rate of reversion to abnormal blood-flow velocities on Doppler studies and stroke. (ClinicalTrials.gov number, NCT00006182 [ClinicalTrials.gov] .)

NEJM Volume 353:2769-2778 December 29, 2005 Number

PMID: 16382063

背景 患有镰状细胞贫血的儿童经经颅多普勒超声检出异常者预防性输血可预防脑卒中。但上述儿童应间隔多长时间输血，目前未明。

方法 我们研究了罹患脑卒中危险的镰状细胞贫血儿童，根据多普勒超声检出的异常，接受输血治疗30个月或以上，其判定标准为输血后多普勒超声检查结果正常。患儿随机分为连续性和非连续性输血组。排除经MRA检出的严重脑血管狭窄者。终止目标为发生脑卒中或多普勒超声提示脑卒中的危险性较高。

结果 计划100例患者，实际79例患者参加入组。在41例停止输血的患儿组，在末次输血后的平均4.5±2.6个月（2.1-10.1个月不等）内，14例出现多普勒超声异常，另外2例发生脑卒中。而38例持续接受输血者则无上述事件发生。输血前最后2次经颅多普勒超声结果的平均值是判断终止目标的唯一因素(P=0.05).。

结论 镰状细胞贫血儿童停止输血以预防脑卒中可致多普勒超声异常血流速度发生率升高和脑卒中的危险性增加。