While the multiple sclerosis (MS) prodrome may be prolonged, healthcare use by sex >5 years pre-onset remains underexplored. We examined healthcare use up to 29 years pre-MS onset, stratified by sex.<\/p>\n
Using administrative data from Ontario, Canada (1991\u20132020), we compared annual physician visit rates by diagnostic chapter between MS and matched non-MS cohorts, stratified by sex. Quasi Poisson models estimated rate ratios (RRs) with 95% confidence intervals (CI).<\/p>\n
Included were 35,018 MS and 136,007 matched non-MS individuals (mean onset age \u223c43 years; standard deviation \u223c14 years; \u223c69% female in both cohorts). Sex differences were observed for nervous system-related visits; males exhibited higher RRs from 10 years pre-onset (\u2018year -10\u2032), peaking in year -1 for both sexes (RRs: males=28.60;95%CI:24.10\u201334.00, females=13.60;95%CI:12.56\u201314.70). This was followed by mental disorders, being higher for males from year -4, peaking in year -1 (RRs: males=2.98;95%CI:2.73\u20133.25; females=2.09;95%CI:1.99\u20132.21), then ill-defined signs\/symptoms and injury-related visits from year -3 to -1 (e.g., ill-defined signs\/symptoms, RRs range: males=1.85\u20134.26 and females=1.67\u20133.27). Additionally, males had higher RRs in the 1\u20132 years pre-onset for respiratory, genitourinary, musculoskeletal, circulatory, digestive, and infection-related visits.<\/p>\n
Sex differences in healthcare use were evident up to 10 years pre-MS onset across multiple diagnostic chapters. Findings suggest that prodromal MS patterns differ by sex, potentially reflecting differences in symptom presentation, health-seeking behaviour, or diagnostic recognition before MS onset.<\/p>\n","protected":false},"excerpt":{"rendered":"
While the multiple sclerosis (MS) prodrome may be prolonged, healthcare use by sex >5 years pre-onset remains underexplored. We examined healthcare use up to 29 years pre-MS onset, stratified by sex. Using administrative data from Ontario, Canada (1991\u20132020), we compared annual physician visit rates by diagnostic chapter between MS and matched non-MS cohorts, stratified by […]<\/p>\n","protected":false},"template":"","migration-helper-automated":[],"migration-manual":[],"topic":[62,51],"migration-helper-qa-sample-set":[],"class_list":["post-24294","journal_article","type-journal_article","status-publish","hentry","topic-health-services-research","topic-musculoskeletal-diseases-and-disorders"],"acf":{"citation":"Amini F, Everett K, Zhu F, Li P, McKay KA, Zhao Y, Maxwell CJ, Marrie RA, Tremlett H. Mult Scler Relat Disord<\/em>. 2026; Jul 2 [Epub ahead of print].","source_url":"https:\/\/doi.org\/10.1016\/j.msard.2026.107360","ices_scientist":[1322],"site":[6733],"research_program":[6746],"news_release":"","journal_article":"","atlas":"","research_report":"","infographic":"","video":"","downloads":null,"links":null,"sitecore_item_id":"","sitecore_item_name":"","sitecore_field_values":"","previous_url":""},"yoast_head":"\n