Gender ratio trends over time in multiple sclerosis patients from Argentina.

Several studies in multiple sclerosis (MS) suggest a trend of increasing disease frequency in women during the last decades. A direct comparison of gender ratio trends among MS populations from Argentina remains to be carried out. The objective of the study was to compare gender ratio trends, over a 50-year span in MS populations from Argentina. METHODS: multicenter study that included patients from 14 MS Centers of Argentina. Patients with definite MS with birth years ranging from 1940 to 1989 were included. Gender ratios were calculated by five decades based on year of birth and were adjusted for the F/M born-alive ratio derived from the Argentinean national registry of births. The F/M ratios were calculated using a multivariate logistic regression per five decades by the year of birth approach. Analyses were performed using Stata 10.1. RESULTS: 1069 patients were included. Gender ratios showed a significant increase from the first to the last decade in the whole MS sample (from 1.8 to 2.7; p value for trend=0.023). The Gender ratio did not show differences considering MS subtype. CONCLUSION: our study showed a modest increase of the F/M ratio (from 1.8 to 2.7) over time among patients affected by MS in Argentina.

Increasing prevalence of multiple sclerosis in Buenos Aires, Argentina.

UNLABELLED: In 1996, the prevalence of multiple sclerosis (MS) for the metropolitan area of Buenos Aires using the capture-recapture method was estimated to be between 14 and 19.8 cases per 100,000 inhabitants. The aim of this study was to update the prevalence to 2014 following the same methodology. METHODS: Gran Buenos Aires is the denomination that refers to the megalopolis comprised by the autonomous city of Buenos Aires and the surrounding conurbation of the province of Buenos Aires. The study was carried out taking December 2014 as the prevalence month. We used the capture-recapture method to estimate the prevalence of MS cross-matching registries from 6 MS Centers from the metropolitan area of Buenos Aires. Log-linear model Poisson regression was used to estimate the number of affected MS patients not detected by any of the 6 sources considered. RESULTS: 1035 registries were obtained from the 6 lists from 910 different patients detected. The population of the area based on 2010 census was 12,806,866, the number of MS cases estimated amongst source interactions were 4901. The estimated prevalence was 38.2 per 100,000 inhabitants (95% CI 36.1-41.2). CONCLUSION: The study is an update almost 20 years after the first one in the area showing a significant increase in the previous reported prevalence. Our findings are in line with previous studies performed in other regions of the world.

Disease onset in familial and sporadic multiple sclerosis in Argentina.

UNLABELLED: The present study was carried out to assess if there is an anticipation of age at onset in younger generations of familial multiple sclerosis (FMS) vs. sporadic MS (SMS) in Argentina. METHODS: multicenter study that included patients from 14 MS Centers of Argentina. Patients were considered as FMS if they had in their family at least one relative of first or second degree diagnosed with MS; otherwise, patients were considered to have SMS. We compared the age at onset between familial and sporadic cases as well as the age at onset between relatives from different generations in FMS vs. SMS. RESULTS: 1333 patients were included, 97 of them were FMS (7.3%). A lower age at onset in the younger generations of FMS cases was found compared with older generations of FMS as well as. SMS cases (24.1±3.7 years vs. 30.3±5.7 years, and 32.4±9.4 respectively; p<0.001). No differences were observed between older generations of FMS vs. SMS cases (p=0.12). CONCLUSION: we observed an anticipation of age at onset of MS in younger generations of patients with FMS vs. older generations of FMS and SMS.