Hippocampal impairment in patients with Essential Tremor. (March 2020)

• Record Type: Journal Article
• Authors: Novellino, Fabiana; Vasta, Roberta; Saccà, Valeria; Nisticò, Rita; Morelli, Maurizio; Arabia, Gennarina; Chiriaco, Carmelina; Barbagallo, Gaetano; Nicoletti, Giuseppe; Salsone, Maria; Quattrone, Aldo
• Is Part Of: Parkinsonism & related disorders. Volume 72(2020)
• Page Start: 56
• Page End: 61
• Publication Date: 2020-03
• Subjects: Essential tremor -- Hippocampus -- Memory -- Structural MRI -- Mean diffusivity; Parkinson's disease -- Periodicals; Movement disorders -- Periodicals; Movement Disorders -- Periodicals; Nerve Degeneration -- Periodicals; Nervous System Diseases -- Periodicals; Parkinson Disease -- Periodicals; Tremor -- Periodicals; Parkinson, Maladie de -- Périodiques; Parkinson's disease; 616.833
• DOI: 10.1016/j.parkreldis.2020.02.006
• Languages: English
• ISSNs: 1353-8020

Abstract

Abstract: Introduction: There is growing evidence that a proportion of patients with Essential Tremor (ET) may develop a memory impairment over time. However, no studies have evaluated whether hippocampal damage really occur in ET. This study investigated the macro and micro-structural integrity of the hippocampus in ET subjects using a multimodal MRI approach. Methods: Neuropsychological and MRI data were acquired from 110 participants (60 patients with ET and 50 age-, sex-, and education-matched healthy controls [HC]). Whole-brain T1-weighted and Diffusion Tensor Imaging (DTI) were performed to assess macro-and microstructural alterations. MRI parameters (volume; mean diffusivity [MD]; fractional anisotropy [FA]) of bilateral hippocampi were obtained. In order to evaluate the relationship between MRI alterations and neurocognitive impairment, hippocampal parameters were also correlated with cognitive test scores. Results: Compared to controls, ET patients showed a subclinical memory impairment with significantly lower memory scores, but within the normal ranges. Despite the subclinical damage, however, ET patients showed a significant increase in MD values in the bilateral hippocampi in comparison with HC. A significant correlation was also found between MD and memory scores in ET. Conclusion: This study improves the knowledge on memory impairment in ET, as our results demonstrate for the first time the hippocampal microstructural damage related to subclinical memory impairment in ET patients. Further studies are needed before these findings can be considered predictive of a distinct ET subtype or suggestive of a co-occurent dementia. Highlights: We found a subclinical memory impairment in ET patients. We found a significant increase of MD values in bilateral hippocampi of ET subjects. We found a correlation between hippocampal MD values and memory scores in ET. Our results offer new evidence of hippocampal damage in ET, related to memory loss.