Essential tremor: epidemiology, etiology, diagnostics and treatment

Evelina Stankevičiūtė1

1Lithuanian University of Health Sciences

Abstract

Essential tremor (ET) is a progressive neurodegenerative disorder which usually manifests as asymmetrical upper limbs tremor. It is the most common movement disorder  and affects about 1% of population worldwide. This disease in most cases affects eldery but also occurs in both young adults and children. More than half of cases have family history of ET and a typical autosomal dominant pattern. Tremor may also present in other locations like head, vocal cords, lower limbs. Essential tremor can cause great difficulties of daily and social activities or even disability as disease progresses. The diagnosis is generally based on detailed assessment of patient‘s complaints, history and neurological examination. It is essential to differentiate from other tremor associated conditions like Parkinson‘s disease, psychogenic tremor, hyperthyroidism. Treatment for essential tremor can be grouped in three main categories: pharmacologic, surgical and non-pharmacologic/non-surgical treatment methods. Continuous or intermittent pharmacotherapy is the first line treatment for essential tremor. Propranolol and primidone are considered as a first line medications for treatment of ET. According to studies pharmacotherapy with propranolol or primidone is effective in about 50-70% of patients. Treatment with a combination of propranolol and primidone may be used when monotherapy is not effective. Surgical treatment is recommended if tremor is disabling and refractory to pharmacotherapy. Deep brain stimulation and magnetic resonance imaging guided high intensity focused ultrasound are the two main surgical treatment approaches. Ventral intermedius nucleus of the thalamus is the primary target for surgical treatment approaches. Many patients feel embarrassment and are depressed  therefore psychological services and support is of great importance.

Keywords: essential tremor, tremor, diagnostics, treatment.