Background:Orthostatic hypotension (OH) at an early stage of Parkinson’s disease (PD) predicts poor prognosis, which may suggest degeneration of dopaminergic neurons affects sympathetic function, causing OH. Objective:We tested the hypothesis that striatal dopaminergic depletion is associated withOH in PD. Methods:Out of 99 patients with newly diagnosed untreated PD, 81 patients were enrolled according to our selection criteria. All patients underwent head-up tilt-table testing and striatal 123I-2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl) nortropane (123I-FP-CIT) dopamine transporter single photon emission computed tomography (DAT-SPECT). DaTQUANT software (GE Healthcare) was used as a semi-quantitative tool to analyze DAT-SPECT data. The association between hemodynamic changes and 123I-FP-CIT uptake was examined. Results: 123I-FP-CIT uptake in the putamen, especially the anterior part and left side, was related not only to motor severity but also to OH. Change in systolic blood pressure correlated negatively with 123I-FP-CIT uptake in bilateral anterior putamen (left: p < 0.01, right: p < 0.05) and left posterior putamen (p < 0.05). Patients with OH had more severe dopamine depletion in left anterior (p = 0.008) and posterior (p = 0.007) putamen at a similar motor severity than did patients without OH even though both groups have similar baseline characteristics. An analysis of asymmetry index showed patients with OH had symmetrically decreased dopamine levels in anterior putamen when compared to those without OH (p = 0.024). Conclusion:OH is closely related to striatal dopamine depletion in PD. This relation may help to account for the prognostic value of OH.

中文翻译：

---

新发帕金森病中体位性低血压的多巴胺能相关性

背景：帕金森病（PD）早期体位性低血压（OH）预示着不良预后，这可能提示多巴胺能神经元变性影响交感神经功能，导致OH。目的：我们检验了纹状体多巴胺能耗竭与 PD 中的 OH 相关的假设。方法：在 99 例新诊断的未经治疗的 PD 患者中，根据我们的选择标准纳入 81 例患者。所有患者都接受了平视倾斜试验和纹状体 123I-2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl) nortropane (123I-FP-CIT) 多巴胺转运蛋白单光子发射计算机断层扫描 (DAT) -SPECT）。DaTQUANT 软件（GE Healthcare）用作分析 DAT-SPECT 数据的半定量工具。检查了血流动力学变化和 123I-FP-CIT 摄取之间的关联。结果：壳核中的 123I-FP-CIT 摄取，尤其是前部和左侧，不仅与运动严重程度有关，而且与 OH 相关。收缩压的变化与双侧前壳核（左：p < 0.01，右：p < 0.05）和左后壳核（p < 0.05）的 123I-FP-CIT 摄取呈负相关。与没有 OH 的患者相比，OH 患者的左前 (p = 0.008) 和后 (p = 0.007) 壳核的多巴胺消耗更严重，运动严重程度相似，尽管两组具有相似的基线特征。不对称指数分析显示，与没有 OH 的患者相比，患有 OH 的患者前壳核中的多巴胺水平对称降低（p = 0.024）。结论：OH与PD纹状体多巴胺耗竭密切相关。