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

Background and purposeThe 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 methodsA 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.ResultsIn 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).ConclusionsIn 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.     

Increased prevalence of silent myocardial ischaemia and severe ventricular arrhythmias in untreated patients with Alzheimer's disease and mild cognitive impairment without overt coronary artery disease

OBJECTIVE: To assess the prevalence and the characteristics of silent myocardial ischaemia (SMI) and ventricular arrhythmias (VA) in subjects with Alzheimer's disease (AD) and mild cognitive impairment (MCI) and their relationships with QT interval dispersion (QTD). METHODS: Thirty-three subjects with AD, 39 subjects with MCI, and 29 cognitive healthy control subjects matched for demographic characteristics, hypertensive condition, smoking habits, and laboratory parameters were enrolled. Each subject underwent clinical and cognitive examination, a structural brain imaging study, electrocardiogram (ECG), 24-h ECG recording, 24-h blood pressure monitoring, and echocardiogram. Detection and characterization of QT dispersion, SMI and VA were performed. RESULTS: The three groups were comparable regarding demographic and basal cardiovascular characteristics: notwithstanding this, SMI episodes were observed only in AD and MCI patients (19 and 14, respectively). A significantly greater prevalence of repetitive ventricular premature beats was observed in AD (mean 8.56+/-13.1) and in MCI (1.8+/-7.2) vs. control (0.7+/-1.7). The QTD, the ischaemic burden and the number of repetitive ventricular beats revealed to be significantly related. CONCLUSIONS: Increased prevalence of SMI and potentially ominous VA were found in AD and, to a lesser extent, in MCI. SMI and repetitive VA were significantly related with QTD. These findings could be related to an increased risk of sudden cardiac death in AD and MCI patients.     

Exploratory assessment of serological tests to determine antibody titer against SARS‐CoV‐2: Appropriateness and limits

BackgroundSerological tests can be used to detect antibodies in the serum of subject''s after SARS‐CoV‐2 infection and vaccination. Currently, variability in antibody titers and the availability of a multiplicity of serological tests have made it necessary to highlight their appropriateness and limitations in various diagnostic settings.MethodsThis study is part of Covidiagnostix, a multicenter project aimed at the assessment of the health technology used in SARS‐CoV‐2 serological tests. Based on data gained from the analysis of over 5000 subjects, a selected number of serum samples, representative of different diagnostic settings, were analyzed first by qualitative immunoassays (IgA, M, and G MILLIPLEX^® SARS‐CoV‐2 tests based on Luminex^®) to define the immunoglobulins serum composition and subsequently by four serological diagnostic tests (Elecsys Anti‐SARS‐CoV‐2 and Elecsys Anti‐SARS‐CoV‐2 S by Roche, SARS‐CoV‐2 IgG by Siemens Healthcare, and CHORUS SARS‐CoV‐2 “NEUTRALIZING” Ab by DIESSE). The first WHO International Standard for SARS‐CoV‐2 was also analyzed using the same methods.ResultsThis study evaluated the antibody content and titer of the WHO Standard and serum of subjects with/without previous infection and before/after vaccination for SARS‐CoV‐2.ConclusionThe definition of antibodies in the WHO standard and the analysis of serum samples allowed for the identification of the appropriateness of serological tests in each diagnostic setting, increasing the effectiveness of the resulting laboratory data. Furthermore, we found that it would be optimal to produce new international standards against the S1 domain and RBD of the SARS‐CoV‐2 spike protein for a more effective serological monitoring of vaccination.