Distribution of sickle cell disease and assessment of risk factors based on transcranial Doppler values in the Gulf region

<b>Background/Objective:</b> Stroke is a potentially fatal complication of sickle cell disease (SCD). Transcranial Doppler (TCD) is useful at identifying increased risk of stroke in children with SCD and vasospasm after subarachnoid hemorrhage. The main aim of this study was to determine the proportion of patients with SCD in the Gulf region who are at a high risk of stroke, as determined by TCD. <b>Methods:</b> This multicenter (Oman, Qatar, and UAE), descriptive, cross-sectional study in patients (aged 2–16 years) with SCD included a baseline visit, 1 follow-up visit for patients with conditional TCD, and 3-year retrospective data analysis for all patients. <b>Results:</b> Of the 410 eligible patients (Oman, 86.5%; Qatar, 8.2%; UAE, 5.1%), most had a TCD finding (left side, 91.7%; right side, 92.0%) of normal velocity (&lt;155 cm/s) at baseline. For 6 of 7 patients with conditional velocity (155–179 cm/s) and 1 patient with high velocity (≥180 cm/s), baseline TCD results were not confirmed at follow-up. As per bivariate linear regression, age, race, transfusion type, and transfusion frequency were significant predictors of the TCD velocities. Multivariate logistic regressions revealed that TCD velocities were significantly correlated with sex, race, and type of transfusion. No patients reported any adverse events at follow-up. No deaths occurred during the study. <b>Discussion/Conclusions:</b> The study results show that far fewer patients with SCD in the Gulf have abnormal TCD findings than the internationally reported. Larger studies are needed to identify the factors underlying this observation.

<b>背景与研究目标：</b> 脑卒中（Stroke）是镰状细胞病（sickle cell disease, SCD）的潜在致命并发症。经颅多普勒超声（Transcranial Doppler, TCD）可用于识别镰状细胞病患儿的脑卒中高发风险，以及蛛网膜下腔出血（subarachnoid hemorrhage）后的血管痉挛（vasospasm）情况。本研究的核心目标为明确海湾地区镰状细胞病患者中，经TCD检测判定为脑卒中高风险人群的占比。
<b>研究方法：</b> 本研究为多中心（覆盖阿曼、卡塔尔及阿拉伯联合酋长国，UAE）描述性横断面研究，纳入年龄2至16岁的镰状细胞病患者，研究流程包括基线访视、针对TCD结果处于临界范围的患者开展1次随访访视，以及对所有患者的3年回顾性数据分析。
<b>研究结果：</b> 本研究共纳入410名符合入组标准的患者（阿曼占86.5%；卡塔尔占8.2%；阿联酋占5.1%），其中多数患者的基线TCD检测结果显示双侧血流速度正常（左侧占比91.7%，右侧占比92.0%，血流速度<155 cm/s）。对于7名TCD临界流速（155~179 cm/s）患者中的6名，以及1名高流速（≥180 cm/s）患者，其随访时的TCD结果未证实基线检测结果。双变量线性回归分析显示，年龄、种族、输血类型及输血频率是TCD血流速度的显著预测因子。多因素logistic回归分析结果表明，TCD血流速度与性别、种族及输血类型显著相关。随访期间无患者报告不良事件，研究全程未发生死亡病例。
<b>讨论与结论：</b> 本研究结果显示，海湾地区镰状细胞病患者中TCD检测结果异常的比例远低于国际报道数据。未来需开展更大规模的研究，以明确该现象背后的潜在影响因素。