Incidence of vascular hemiballism in the population of Belgrade.

Hemiballism is a relatively rare hyperkinetic disorder with unknown incidence. Stroke is the most common cause of hemiballism (vascular hemiballism), responsible for the disorder in 50% to 100% of cases. We studied the incidence of vascular hemiballism in the population of Belgrade (Serbia) 40 years of age or older during the period 1 January 1991 to 31 December 2002. During that time period, 37 patients with hemiballism due to stroke were diagnosed. The annual incidence rates varied from 0.14 to 0.87/100,000 (average 0.45/100,000) of general population.