General reviewNews and controversies regarding essential tremorActualités et controverses concernant le tremblement essentiel
Section snippets
Definition of essential tremor: towards new clinical criteria?
ET is characterized by a postural and kinetic tremor of the upper limbs, sometimes involving the head (30%) and more rarely the face, voice, trunk and legs. Age, family history of tremor and Caucasian ethnic background are risk factors for ET [1], [2], [3]. Age of onset has a bimodal distribution, with a first peak in the 20–40 years age range and a second higher peak after 65 years [4]. Prevalence estimates have been quite variable, mainly because of difficult diagnosis and access to care. In
New developments in the pathophysiology of essential tremor
Although many elements of the pathophysiology of ET remain unclear, research over the last decade has greatly affected our underlying approach to this disorder; some advances have been made in unraveling the different symptomatic and etiological aspects. Two opposing pathophysiological concepts can be described, one based on the hypothesis of a single-symptom disease arising from a functional disorder related to a neuronal oscillator [42] and the other considering “tremor syndrome” to be a more
What is the link between essential tremor and Parkinson's disease?
The presence of a link between ET and idiopathic Parkinson's disease (PD) remains highly controversial. The co-existence of these two commonly encountered disease states in the same patient could be incidental. There are however epidemiological, genetic and pathological data suggesting that ET could be a risk factor for developing PD [89].
It is not rare that patients with longstanding ET develop clinical manifestations of resting tremor. This tremor generally occurs alone, with no other sign of
Drug therapy
While there is no curative treatment for ET, several drug regimens are available that provide relief for about half of treated patients. First-intention drug therapy is based on two main compounds: propanolol and primidone. Both have proven efficacy demonstrated with double-blind randomized controlled trials, with a 50–60% reduction in tremor (88%). Propanolol is a non-selective beta-adrenergic blocker: symptom improvement is observed in 50–70% of patients taking a daily dose of 240–320 mg, with
Conclusion
Despite many unknowns, research advances over the last 20 years have provided us with a better understanding of the complex pathophysiology of ET. Evidence is pointing towards dysfunctional cerebello-thalamo-cortical loops, although the underlying cause remains unknown. Recent imaging, electrophysiological, and anatomopathological data have led to the emergence of two highly-debated pathophysioloical concepts: one supports a neurodegenerative origin of the disorder; the other proposes the
Disclosure of interest
The authors declare that they have no conflicts of interest concerning this article.
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Pesticides and tremor: An overview of association, mechanisms and confounders
2023, Environmental ResearchThe thermodynamic soliton theory of the nervous impulse and possible medical implications
2022, Progress in Biophysics and Molecular BiologyCitation Excerpt :Essential tremor (ET) is among the most common movement disorders. It consists of tremor of the upper limbs, for reviews see (Elble, 2013; Boutin et al., 2015). Essential tremor is often diagnosed when other origins of tremor can be ruled out (Espay et al., 2017).
Psychosocial factors and perceived tremor disability in essential tremor
2020, Neuroscience and Biobehavioral ReviewsCitation Excerpt :Essential tremor (ET) is characterized by a wide range of motor and non-motor symptoms (Benito-Len and Louis, 2006; Holding and Lew, 2019; Lacritz et al., 2002; Lee et al., 2015; Louis and Okun, 2011). Psychological factors associated with ET remains unclear (Holding and Lew, 2019; Boutin et al., 2015; Thenganatt and Louis, 2012). While there is limited evidence suggesting the efficacy of pharmacotherapy for ET (Lundervold et al., 1999), literature suggests poor satisfaction with medical care among ET patients (Louis et al., 2015).
Surgical treatments for tremors
2018, Revue NeurologiqueCitation Excerpt :Tremor severity usually increases with time inducing severe physical impairment and a markedly decrease in quality of life. Its management is challenging as pharmacological treatments are often disappointing with partial efficacy and relative tolerance [1,2]. Surgical therapies for medically refractory tremors are expanding.
Developing a Staging Scheme for Essential Tremor: A Discussion of Organizing Principles
2023, Tremor and Other Hyperkinetic Movements