D'Arcy Little, MD, CCFP, Director of Medical Education, York Community Services, Toronto, ON and Academic Fellow, Department of Family and Community Medicine, University of Toronto, Toronto, ON.
Introduction
Movement disorders have a high prevalence in the elderly. In fact, disorders of gait and mobility are second only to cognitive impairment as the most prevalent neurologic disorders of aging.1 Huntington's disease (HD) is an inherited neurodegenerative disorder characterized by alterations in mood, memory and movement first described by George Huntington in 1872.2,3 Recent advances in the elucidation of the pathophysiology of this disease may have implications in the development of more specific and effective treatments. The following article will review the epidemiology, pathophysiology, clinical presentation, diagnosis and treatment of HD, including novel treatments currently under development.
Epidemiology
HD is the most important cause of hereditary chorea. Its prevalence in the Caucasian population is thought to be as high as 10 per 100,000.4 However, because many gene carriers have yet to develop symptoms, the actual prevalence is more than twice the number of symptomatic cases. HD is uncommon in Finland, Norway, Japan, China, and in persons of African descent, but is greatly increased along the western shore of Lake Maracaibo, Venezuela.5 The condition affects both genders equally.
