Odor Identification Test in Idiopathic REM-Behavior Disorder and Parkinson's Disease in China.

Background: Olfactory dysfunction is common in Parkinson's disease (PD) and idiopathic rapid eye movement sleep behavior disorder (iRBD), which is a risk factor in the development of PD. However, a few studies have conflicting results when comparing dysosmia in the patients with iRBD and PD. There is no study investigating the olfactory function in Chinese patients with iRBD.

Onset-related subtypes of Parkinson's disease differ in the patterns of striatal dopaminergic dysfunction: A positron emission tomography study.

Purpose: The young-onset subtype of Parkinson's disease (YOPD) differs from the late-onset subtype (LOPD) in drug responsiveness, incidence of motor complications, and prognosis. The pathophysiology underlying these differences remains largely unknown. This study investigated whether the two subtypes differ in the pattern of dysfunction in striatal (caudate and putamen) dopaminergic system and if the dopamine transporter (DAT) imaging patterns are associated with the clinical features of corresponding PD subtype.