Background: The role of nigrostriatal dopaminergic neurons degeneration is well established in the pathophysiology of Parkinson’s disease. However, it is unclear if and how the degeneration of the dopamine pathways affects the manifestation of the neuropsychiatric symptoms (NPS) of Parkinson’s Disease (PD). Dopamine transporter (DAT) imaging, a technique to measure the reduction in dopamine transporters is increasingly used as a tool in the diagnosis of PD.

Methods: In this study, we examine if the baseline dopamine transporter density in the striatum measured by the Striatal Binding Ratio (SBR) is associated with the longitudinal onset and/or progression of NPS in PD as measured by part 1 of Movement Disorder Society - Unified Parkinson's Disease Rating Scale, over four years. Data of patients with PD and an abnormal screening present on 123I-ioflupane single-proton emission computed tomography were obtained from Parkinson's Progression Markers Initiative (PPMI) database. Latent Growth Modeling (LGM), a statistical technique that can model the change over time while considering the variability in the rate of change at the individual level, was used to examine the progression of NPS over time.

Results: The results indicate the SBR did not correlate with the baseline NPS but did correlate with the rate of change of NPS (p<0.001) over the next four years, even after eliminating age-related variance, which can be a significant confounding factor.

Conclusion: In conclusion, this study showed gradual worsening in NPS in patients with Parkinson’s disease, which inversely correlates with the density of the dopamine transporters as measured by SBR at baseline.

背景：黑质纹状体多巴胺能神经元变性的作用在帕金森病的病理生理学中得到了很好的证实。然而，目前尚不清楚多巴胺通路的退化是否以及如何影响帕金森病 (PD) 的神经精神症状 (NPS) 的表现。多巴胺转运蛋白 (DAT) 成像是一种测量多巴胺转运蛋白减少的技术，越来越多地用作诊断 PD 的工具。

方法：在这项研究中，我们检查了通过纹状体结合率 (SBR) 测量的纹状体中的基线多巴胺转运蛋白密度是否与运动障碍协会第 1 部分测量的 PD 中 NPS 的纵向发作和/或进展相关 -统一帕金森病评定量表，超过四年。PD 患者的数据和 123I-ioflupane 单质子发射计算机断层扫描出现异常筛查的数据来自帕金森病进展标志物倡议 (PPMI) 数据库。潜在增长模型 (LGM) 是一种统计技术，可以模拟随时间的变化，同时考虑个体水平变化率的可变性，用于检查 NPS 随时间的进展。

结果：结果表明，SBR 与基线 NPS 无关，但与未来四年的 NPS 变化率（p<0.001）相关，即使在消除了与年龄相关的方差之后，这可能是一个重要的混杂因素.

结论：总之，这项研究表明帕金森病患者的 NPS 逐渐恶化，这与 SBR 在基线时测量的多巴胺转运蛋白的密度成反比。