Z.A. ZALYALOVA^1, 2, S.E. MUNASIPOVA^1, 2, M.M. ERMAKOVA¹

 ¹Kazan State Medical University, Kazan

²Center for Movement Disorders and Botulinum Therapy of the Republic of Tatarstan, Kazan

 Contact details:

Ermakova M.M. — post-graduate student of the Department of Neurology and Rehabilitation

Address: 49 Butlerov St., Kazan, Russian Federation, 420012, tel.: +7-905-342-46-49, e-mail: esenia171@rambler.ru

Essential tremor (ET) is the most common movement disorder, the main manifestation of which is progressive postural-kinetic tremor of the extremities, the pattern most often involving the hands. According to the latest classification, 2 different groups of patients with essential tremor are distinguished: patients with tremor (ET) and patients in whose clinic there are additional symptoms in addition to tremor (ET-plus syndrome, ET-P).

The purpose was to identify and compare cognitive impairment in patients with essential tremor and essential tremor plus syndrome.

Material and methods. A prospective study of 41 patients with essential tremor was performed at the Center for Movement Disorders and Botulinum Therapy of the Republic of Tatarstan using clinical, anamnestic and statistical methods for collecting and analyzing data.

Results. Patients of both groups were comparable in terms of the disease duration, the frequency of family cases occurrence, and gender. While changes in cognitive functions are heterogeneous in different groups, ET-P patients show changes in visual-spatial functions, speech and short-term memory, which forms an amnestic type of intellectual impairment. The heterogeneity of the clinic of ET-P patients may indicate the involvement of various brain structures, in addition to the cerebellum, in the pathophysiological process.

Key words: tremor, essential tremor, ET-plus syndrome, cognitive impairment.

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