{
  "abstract": "Background Increased healthcare use precedes classical multiple sclerosis (MS) symptom onset. Limited evidence exists on sex and age variation. We assessed physician visit patterns pre-MS onset by sex and age.Methods Using data from British Columbia, Canada, we compared annual physician visit rates (overall, by reason and specialty) in the 15 years before the neurologist-determined MS symptom onset date (index) and a matched non-MS cohort, stratified by sex and age (<30, 30–49, ≥50).Results We included 2038 MS and 10 182 non-MS persons (74% female). Mean age (years) at index was 37.6 (females) and 38.7 (males). Compared with matched non-MS persons, females with MS showed earlier and more consistent elevations in physician visits (years −14 to −1), while males had sporadic elevations (years −5, –3 and −1). Females also had longer periods of elevated rate ratios (RRs) for ill-defined signs/symptoms (years −15 to −1), mental disorders (years −14 to −1 except year −7) and musculoskeletal conditions (years −6 to −1). Females exhibited sustained elevated visits by specialty, including general practice (all years; RR ≥1.1), psychiatry (years −12 to −1 except −8 to −6; RRs ≥1.6) and ophthalmology (years −9 to −1 except −2; RRs ≥1.4). Compared with matched non-MS counterparts, those aged 30–49 years had sustained higher RRs for psychiatry visits (years −12 to −1 except −8 and −6; RRs ≥1.9) and ophthalmology (years −9 to −1; RRs ≥1.4). Other age groups had fewer elevated RRs preindex. Across comparisons, RRs were of similar magnitude across sex and age groups.Conclusions Sex-specific and age-specific differences in physician visits extended up to 15 years pre-MS onset, suggesting a durable prodromal signature, most evident in females and those aged 30–49 years.",
  "authors": [
    {
      "affiliations": [
        "Faculty of Medicine (Neurology), University of British Columbia and The Djavad Mowafaghian Centre for Brain Health, Vancouver, BC, Canada"
      ],
      "name": "Marta Ruiz-Algueró"
    },
    {
      "affiliations": [
        "Faculty of Medicine (Neurology), University of British Columbia and The Djavad Mowafaghian Centre for Brain Health, Vancouver, BC, Canada"
      ],
      "name": "Feng Zhu"
    },
    {
      "affiliations": [
        "Faculty of Medicine (Neurology), University of British Columbia and The Djavad Mowafaghian Centre for Brain Health, Vancouver, BC, Canada"
      ],
      "name": "Farahnaz Amini"
    },
    {
      "affiliations": [
        "Faculty of Medicine (Neurology), University of British Columbia and The Djavad Mowafaghian Centre for Brain Health, Vancouver, BC, Canada"
      ],
      "name": "Yinshan Zhao"
    },
    {
      "affiliations": [
        "Department of Internal Medicine (Neurology), Max Rady College of Medicine, Rady Faculty of Health Science, University of Manitoba, Winnipeg, MB, Canada",
        "Department of Medicine and Community Health and Epidemiology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada",
        "Nova Scotia Health, Halifax, NS, Canada"
      ],
      "name": "Ruth Ann Marrie"
    },
    {
      "affiliations": [
        "Faculty of Medicine (Neurology), University of British Columbia and The Djavad Mowafaghian Centre for Brain Health, Vancouver, BC, Canada"
      ],
      "name": "Helen Tremlett"
    }
  ],
  "title": "Sex-related and age-related differences in healthcare use before multiple sclerosis symptom onset: a matched cohort study",
  "uid": "ad79136b-9646-5e7f-9fe4-4b6182579449"
}