Non-motor features of essential tremor with midline distribution

• Published in: Neurological sciences 2022-10, Vol.43 (10), p.5917-5925
• Main Authors: Rekik, Arwa, Nasri, Amina, Mrabet, Saloua, Gharbi, Alya, Souissi, Amira, Gargouri, Amina, Kacem, Imen, Gouider, Riadh
• Format: Article
• Language: English
• Subjects: Autonomic nervous system; Cerebellum; Cognitive ability; Dysautonomia; Electrophysiological recording; Extrapyramidal system; Jaw; Medicine; Medicine & Public Health; Mental disorders; Neurology; Neuroradiology; Neurosciences; Neurosurgery; Original Article; Patients; Phenotypes; Psychiatry; Tremor; Tremor (Muscular contraction)
• ISSN: 1590-1874; 1590-3478
• DOI: 10.1007/s10072-022-06262-x

Background Midline essential tremor (Mid-ET) is a distinctive group of essential tremor (ET) in which tremor affects the neck, jaw, tongue, and/or voice. For long, it has been considered as an ultimate stage of the disease and a marker of its severity. However, recent studies pointed its complexity in terms of non-motor presentation. Thus, we aimed to investigate the non-motor signs (NMS) in Mid-ET. Design We conducted a cross-sectional study in a tertiary neurology referral center including ET patients classified into two groups based on the presence or not of midline tremor (Mid-ET vs. No-Mid-ET). We assessed NMS using the non-motor severity scale (NMSS), a large battery of cognitive tests, clinical and electrophysiological study of the autonomic nervous system along with the evaluation of sleep disturbances. Results A total of 163 patients were included: Mid-ET ( n  = 79) and No-Mid-ET ( n  = 84) matched in gender and age of onset. Mid-ET patients had higher proportion of late-onset ET (> 60 years old, p  = 0.002) and more extrapyramidal signs ( p  = 0.005). For NMS, Mid-ET was marked with cognitive dysfunction ( p  = 0.008). The hallmarks of the neuropsychiatric profile of Mid-ET were executive dysfunction ( p  = 0.004), attention problems ( p