Background: There is emerging awareness that movement disorders rank among the most common neurological diseases. However, the overall burden of these disorders in the general community is not well defined. We sought to assess the prevalence of all common categories of movement disorders in a population, accounting for sex differences and age trends.
Methods: As part of an ongoing prospective population-based study of carotid atherosclerosis and stroke risk (the Bruneck Study), a total of 706 men and women aged 50-89 years underwent a thorough neurological assessment. The diagnosis of movement disorders and ratings for disease severity were based on standard criteria and scales. Prevalences were estimated from logistic regression models (regression-smoothed rates) and standardised to the age and sex structure of the general community.
Findings: The prevalence of all common categories of movement disorders was 28.0% (95% CI 25.9-30.1). Proportions in men (27.6% [95% CI 24.5-30.7]) and women (28.3% [25.5-31.2]) were closely similar and sharply increased with age (from 18.5% [15.0-22.0] in 50-59-year olds to 51.3% [44.9-57.7] in 80-89-year olds). Almost half of all patients (90/214) had moderate-to-severe disease expression, but only 7.0% (15/214) received standard drug treatment. Prevalence of tremor was 14.5%, followed by restless legs syndrome (10.8%), parkinsonism (7%), primary dystonia and secondary dystonia (1.8%), and chorea and tics (<1% each). A fifth of all movement disorders were diagnosed to be probably drug-induced.
Interpretation: There is a high prevalence of and substantial under-recognition and under-treatment of movement disorders in the general community.