Pan-American Consortium of Multiple System Atrophy (PANMSA). A Pan-American multicentre cohort study of multiple system atrophy.

BACKGROUND: Multiple system atrophy (MSA) is an adult-onset and rapidly progressive, neurodegenerative condition that presents with autonomic dysfunction, parkinsonism, cerebellar ataxia and corticospinal deficits. Clinical, demographic and epidemiological data from different regions have provided valuable information concerning the natural history of MSA. There are no published data of Multiple System Atrophy (MSA) in Latin American countries. OBJECTIVE: To describe clinical and epidemiological data of patients with "possible" MSA from seven referral movement disorders centers from Argentina, Chile, Mexico, Peru and United States. METHODS: We conducted a retrospective, observational, cross-sectional Pan-American multicentre cohort study of MSA. RESULTS: The sample was composed of 82 females and 77 men with the diagnosis of "possible" MSA with a mean age at onset of 65 ± 10 years. 67.29% of the individuals had a MSA-P variant with a mean age at onset of 61.47 ± 10.28 years, whereas the mean age at onset in the MSA-C patients was 57.44 ± 10.58 years. Interestingly, MSA-C-was more prevalent in Non-Caucasian (50-Mestizo and 2 Asian patients) than Caucasians (51.92% vs. 20.79%, p = 0.0001). Dysautonomic symptoms were present in 95.6% of the patients, parkinsonism in 85.5%, pyramidal signs in 25.8% and depression in 48.4% of the patients. CONCLUSIONS: Our epidemiological and clinical data appears to be similar to other Western international series, however, of note, the MSA-C phenotype was predominant in Non-Caucasians, more specifically the Mestizo population. This observation opens a new path to explore. Larger prospective epidemiologic studies in Latin America may provide valuable information concerning MSA in the region.

Prevalence of restless legs syndrome: a community-based study from Argentina.

BACKGROUND AND PURPOSE: The number of restless legs syndrome (RLS) prevalence studies performed outside Europe and North America remains small. We conducted a community-based study to estimate the relative prevalence of RLS in Argentina. PATIENTS AND METHODS: A total sample of 471 participants from high (Buenos Aires) and low population density areas (three cities with <35,000 inhabitants), completed a self-assessment questionnaire, including the International Restless Legs Syndrome Study Group (IRLSSG) diagnostic criteria, to determine RLS symptoms. RESULTS: In the present study, the four RLS criteria were reported in 20.2%. In accordance with other studies, we found a female/male ratio of 3:1, with women being younger than men. However, RLS prevalence in "clinically significant" participants, that is symptoms present at least two or more times a week, were 10.8% (12.4% in participants from high population density versus 2.60% in participants from low population density areas). CONCLUSIONS: In the present study, RLS appears as a common disorder in this population. The RLS prevalence found is in agreement with some epidemiological reports from the American and European populations but it is significantly higher than the prevalence reported for Native South Americans (i.e., 0.8-3.2%). These differences could be explained by the composition of the Argentinean population with predominantly European roots. Taking into account the significant impact of RLS on health and quality of life, our study represents a preliminary approach to characterize this chronic disease in this community.