title: Increasing incidence of multiple sclerosis among women in Buenos Aires: a 22 year health maintenance organization based study.
abstract: Studies in multiple sclerosis (MS) suggest a trend of increasing disease prevalence and incidence, and especially, a disproportional increase in the incidence of multiple sclerosis in women. The objective of this study was to evaluate the incidence of MS over 22 years and to determine the ratio in incidence of men to women in a health maintenance organization from Buenos Aires, Argentina. The population was made up of all members of a hospital-based HMO affiliated between January 1992 and December 2013. Each person was followed contributing time at risk. Cases with definite diagnosis of MS were included. Incidence density was calculated with 95 % confidence intervals and compared between women and men. 165,456 subjects were followed for a total of 1,488,575 person-years, of whom 42 developed MS. Incidence density was 3/100,000 person-years (95 % CI 2.1-3.5/100,000 person-years). During this period (1992-2013), the incidence rate in women increased from 1/100,000 (95 % CI 0.8-1.6) to 4.9/100,000 (95 % CI 4.1-5.4) (p < 0.001), while in men the incidence ranged from 1.4/100,000 (95 % CI 1-1.7) to 1.8 (1.3-2.1) (p = 0.16). Incidence density during the study period increased significantly in women but not in men. This is the first report of this phenomenon in Latin America region.
authors.affiliation: Centro de Esclerosis Múltiple de Buenos Aires (CEMBA), Italian Hospital of Buenos Aires, Gascón 450, C1181ACH, Buenos Aires, Argentina. edgardo.cristiano@hospitalitaliano.org.ar.
authors.forename: E
authors.initials: E
authors.lastname: Cristiano
authors.affiliation: Centro de Esclerosis Múltiple de Buenos Aires (CEMBA), Italian Hospital of Buenos Aires, Gascón 450, C1181ACH, Buenos Aires, Argentina.
authors.forename: L
authors.initials: L
authors.lastname: Patrucco
authors.affiliation: Centro de Esclerosis Múltiple de Buenos Aires (CEMBA), Italian Hospital of Buenos Aires, Gascón 450, C1181ACH, Buenos Aires, Argentina.
authors.forename: J
authors.initials: J
authors.lastname: Miguez
authors.affiliation: Clinical Research Section, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina.
authors.forename: D
authors.initials: D
authors.lastname: Giunta
authors.affiliation: Clinical Research Section, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina.
authors.forename: J
authors.initials: J
authors.lastname: Peroni
authors.affiliation: Centro de Esclerosis Múltiple de Buenos Aires (CEMBA), Italian Hospital of Buenos Aires, Gascón 450, C1181ACH, Buenos Aires, Argentina.
authors.forename: J I
authors.initials: JI
authors.lastname: Rojas
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D001118:Argentina / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006279:Health Maintenance Organizations / Q000706:statistics & numerical data*; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000453:epidemiology*; D055815:Young Adult
keywords: Argentina; Epidemiology; Incidence; Multiple sclerosis; Sex issue; South America