Clinical features and neurobiochemical mechanisms of olfactory dysfunction in patients with Parkinson disease

This study aimed to investigate clinical features, influencing factors and neurobiochemical mechanisms of olfactory dysfunction (OD) in Parkinson disease (PD). Total 39 patients were divided into the  PD with OD (PD–OD) and PD with no OD (PD–nOD) groups according to overall olfactory function, including threshold, discrimination and identification, assessed by Sniffin’ Sticks test. Motor function and non-motor symptoms were rated by multiple scales. Dopamine, acetylcholine, norepinephrin e and 5-hydroxytryptamine levels in cerebrospinal fluid (CSF) were measured. We found that the PD–OD group showed significantly lower score of Montreal Cognitive Assessment Scale, higher scores of rapid eye movement sleep behavior disorder (RBD) Screening Questionnaire and Epworth Sleepiness Scal e than the PD–nOD group (p <  0.05). RBD Screening Questionnaire score was independently associated with the scores of overall olfactory function and discrimination (p <  0.05). Dopamine and acetylcholine levels in CSF from the PD–OD group was significantly lower than that from the PD–nOD group (p <  0.05). Dopamine and acetylcholine levels in CSF were significantly and positively correlated with the scores of overall olfactory function, threshold, discrimination and identification in PD patients (p <  0.05). RBD Screening Questionnaire score was significantly and negatively correlated with acetylcholine level in CSF in PD patients with poor olfactory d...
Source: Journal of Neurology - Category: Neurology Source Type: research