Evaluation of non-motor symptoms in Parkinson's disease for potential application to early diagnosis

我们调查了帕金森病的非运动症状，并探讨其早期诊断的可用性。快速眼动（REM）睡眠行为障碍（RBD）可能是包括帕金森病在内的α-突触核蛋白病的早期症状。我们研究了在这些情况下报告的认知和自主神经症状是否也在RBD患者中发展。我们还使用多巴胺转运蛋白PET检查了患者是否在黑质纹状体多巴胺能系统中存在临床前神经变性。结果如下。(1)多巴胺转运体PET显示3例RBD患者中有2例黑质纹状体多巴胺能系统突触前功能降低。(2)两名患者的嗅觉识别和社会认知（包括面部表情识别和决策）受损，突触前功能降低。(3)所有患者均出现自主神经体征，如心肌123 I-间碘苄胍（MIBG）摄取减少和便秘。RBD患者的社会认知和自主神经症状与PD患者一致。基于黑质纹状体系统的一致性和突触前功能的降低，我们预测这些RBD患者在不久的将来可能会出现运动症状。

We investigated the non-motor symptoms of Parkinson's disease and explored their availability for early diagnosis. Rapid eye movement (REM) sleep behavior disorder (RBD) can be an early symptom of alpha-synucleinopathies including Parkinson's disease. We examined whether the cognitive and autonomic symptoms reported in these conditions also developed in RBD patients. We also examined whether the patients had preclinical nerve degeneration in the nigrostriatal dopaminergic system using dopamine transporter PET. The results were as follows. (1) The dopamine transporter PET indicated the reduced pre-synaptic function in the nigrostriatal dopaminergic system in 2 out of 3 RBD patients. (2) Olfactory recognition and social-cognition including facial-expression recognition and decision-making was impaired in two patients with the reduced pre-synaptic function. (3) Autonomic signs such as decreased myocardial 123I-metaiodobenzylguanidine (MIBG) uptake and constipation were present in all patients. The social-cognitive and autonomic symptoms in the RBD patients were consistent with those of PD patients. Based on the consistence and the reduced pre-synaptic function in the nigrostriatal system, we predicted that motor symptoms may develop in those RBD patients in the near future.