BACKGROUND AND PURPOSE: In a longitudinal population-based dataset of patients with multiple sclerosis (MS), we have previously observed a substantial increase in the female to male sex ratio in Canada over the last 50 years. Here, we aimed to determine whether this change in sex ratio is related to the clinical course of MS. METHODS: We calculated sex ratios by birth year in 11 868 patients with relapsing-remitting (RR) MS and 2825 patients with primary progressive (PP) MS identified as part of the Canadian Collaborative Project on the Genetic Susceptibility to MS. RESULTS: Year of birth was a significant predictor for sex ratio in RR MS (P < 0.0001, chi(2) = 21.2; Spearman's rank correlation r = 0.67), but not for PP MS (P = 0.44, chi(2) = 0.6; Spearman's rank correlation r = 0.11). CONCLUSIONS: An increase in the number of female RR MS patients over time accounts for the increasing sex ratio of MS. This has implications for pathogenesis, for assessment of clinical trial results and for disease prevention. The factors underlying the selective increase in MS in females need to be uncovered.
BACKGROUND AND PURPOSE: In a longitudinal population-based dataset of patients with multiple sclerosis (MS), we have previously observed a substantial increase in the female to male sex ratio in Canada over the last 50 years. Here, we aimed to determine whether this change in sex ratio is related to the clinical course of MS. METHODS: We calculated sex ratios by birth year in 11 868 patients with relapsing-remitting (RR) MS and 2825 patients with primary progressive (PP) MS identified as part of the Canadian Collaborative Project on the Genetic Susceptibility to MS. RESULTS: Year of birth was a significant predictor for sex ratio in RR MS (P < 0.0001, chi(2) = 21.2; Spearman's rank correlation r = 0.67), but not for PP MS (P = 0.44, chi(2) = 0.6; Spearman's rank correlation r = 0.11). CONCLUSIONS: An increase in the number of female RR MS patients over time accounts for the increasing sex ratio of MS. This has implications for pathogenesis, for assessment of clinical trial results and for disease prevention. The factors underlying the selective increase in MS in females need to be uncovered.
Authors: Karen Ann Ribbons; Patrick McElduff; Cavit Boz; Maria Trojano; Guillermo Izquierdo; Pierre Duquette; Marc Girard; Francois Grand'Maison; Raymond Hupperts; Pierre Grammond; Celia Oreja-Guevara; Thor Petersen; Roberto Bergamaschi; Giorgio Giuliani; Michael Barnett; Vincent van Pesch; Maria-Pia Amato; Gerardo Iuliano; Marcela Fiol; Mark Slee; Freek Verheul; Edgardo Cristiano; Ricardo Fernandez-Bolanos; Maria-Laura Saladino; Maria Edite Rio; Jose Cabrera-Gomez; Helmut Butzkueven; Erik van Munster; Leontien Den Braber-Moerland; Daniele La Spitaleri; Alessandra Lugaresi; Vahid Shaygannejad; Orla Gray; Norma Deri; Raed Alroughani; Jeannette Lechner-Scott Journal: PLoS One Date: 2015-06-05 Impact factor: 3.240
Authors: Maria Trojano; Guglielmo Lucchese; Giusi Graziano; Bruce V Taylor; Steve Simpson; Vito Lepore; Francois Grand'maison; Pierre Duquette; Guillermo Izquierdo; Pierre Grammond; Maria Pia Amato; Roberto Bergamaschi; Giorgio Giuliani; Cavit Boz; Raymond Hupperts; Vincent Van Pesch; Jeannette Lechner-Scott; Edgardo Cristiano; Marcela Fiol; Celia Oreja-Guevara; Maria Laura Saladino; Freek Verheul; Mark Slee; Damiano Paolicelli; Carla Tortorella; Mariangela D'Onghia; Pietro Iaffaldano; Vita Direnzo; Helmut Butzkueven Journal: PLoS One Date: 2012-10-25 Impact factor: 3.240