Essential tremor (ET) is one of the most prevalent movement disorders and neurodegenerative diseases around the world. It is thought to affect approximately 9% of the global population, which would mean that an estimated 2.3 million people in Australia are sufferers.i
ET is a neurological condition that causes the hands – as well as possibly the head, trunk and voice – to shake. Though often confused with Parkinson’s disorder, it is a different condition, and therefore sometimes difficult to diagnose. Age is a widely accepted risk factor, with people over 65 years most likely to experience symptoms.
The cause of ET is not known, though there is evidence of a genetic association. ET is thought to be inherited as an autosomal dominant trait, so children have a 50% chance of developing the disorder if a parent is a sufferer. Two genes have been linked with ET, suggesting that mutation of various genes could lead to the condition. Separate studies linked the ETM1 gene to chromosome 3 and EMT2 has been mapped to chromosome 2.ii
However, several other factors are believed to influence the development of ET in individuals, including environmental and lifestyle factors. In particular, research has been conducted into the impact of diet on the progression of ET. One studyiii suggested that diet might lead to enzymatic changes in the body and therefore increase the risk of mutation. Excessive alcohol and meat consumption may also trigger the onset and severity of ET. As such, there may be some merit in, at least partially, managing a patient’s symptoms by controlling their diet – although more research is needed in the field. For instance, there is some initial evidence that a balanced intake of caffeinated drinks could help to modify disease onset in those with a family history of ET, though, again, a more detailed study is required.iv
Another factor that may serve as a predictor for ET in later life is low physical activity.v It is logical to assume that the physical impairment and involuntary movements ET causes would in turn lead back to reduced physical activity in sufferers. This may well prove to be an early symptom that clinicians could use to manage onset of ET in the future.
For now, it is the responsibility of practitioners to help patients manage their symptoms as well as they can. ET – or indeed, any tremor-causing disorder – can have a significant impact on a patient’s quality of life, affecting physical, psychosocial, communication and leisure aspects of their lives.vi
i Healthport. Essential Tremor Treatment in Australia. https://healthport.com.au/treatments-in-australia-for-essential-tremor/ [Accessed April 2023]
ii National Center for Biotechnology Information (US). Genes and Disease [Internet]. Bethesda (MD): National Center for Biotechnology Information (US); 1998-. Essential tremor. Available from: https://www.ncbi.nlm.nih.gov/books/NBK22186/
iii Ray A, Biswas DA. Association of Diet With Essential Tremor: A Narrative Review. Cureus. 2022 Sep 14;14(9):e29168. doi: 10.7759/cureus.29168. PMID: 36258958; PMCID: PMC9567235.
iv Louis ED, Meyers JH, Cristal AD, Factor-Litvak P. Caffeine Consumption in First-Degree Relatives of Essential Tremor Cases: Evidence of Dietary Modification Before Disease Onset. Neuroepidemiology. 2018;51(1-2):64-70. doi: 10.1159/000489960. Epub 2018 Jun 28. PMID: 29953981; PMCID: PMC6093796.
v Radler KH, Chapman S, Zdrodowska MA, Dowd HN, Liu X, Huey ED, Cosentino S, Louis ED. Physical activity as a predictor of cognitive decline in elderly essential tremor cohort: a prospective longitudinal study. Front. Neurol. May 2021; 12 ISSN=1664-2295. DOI=10.3389/fneur.2021.658527
vi Louis ED, Machado DG. Tremor-related quality of life: A comparison of essential tremor vs. Parkinson's disease patients. Parkinsonism Relat Disord. 2015 Jul;21(7):729-35. doi: 10.1016/j.parkreldis.2015.04.019. Epub 2015 Apr 24. PMID: 25952960; PMCID: PMC4764063.