{
  "abstract": "Objectives: To determine if there are differences in Hemoglobin A1C (A1C) trajectory by sex among children and youth living with type 1 diabetes and to examine how this would be modified by body mass index (BMI).\n\nDesign: Retrospective cohort study using the British Columbia Pediatric Diabetes Registry (BC-PDR), a provincial paediatric diabetes registry that started enrolling patients in 2017 and included data up to 2 years prior to enrolment.\n\nSetting: Data were extracted from the BC-PDR (British Columbia, Canada) in July 2023 and included data from 2016 to 2023.\n\nParticipants: 674 individuals diagnosed with type 1 diabetes in childhood and adolescence (299 females, 375 males).\n\nPrimary and secondary outcome measures: We extracted demographic data, clinical characteristics and longitudinal A1C values from the BC-PDR. We plotted A1C trajectories by sex and BMI categories. We used generalised additive models to flexibly examine A1C trajectories by age and compared these by sex. We further examined whether the association between age- and sex-specific A1C differed between BMI categories.\n\nResults: At age 5, there was no difference in mean A1C by sex (mean difference=−0.03%, 95% CI −0.21% to 0.15%, p=0.73), but by age 14, males had a lower mean A1C compared with females (mean difference=0.15%, 95% CI 0.04% to 0.25%, p=0.01). This difference was even greater by age 18 (mean difference=0.77%, 95% CI 0.59% to 0.94%, p<0.001). Mean A1Cs were higher in females with a BMI in the overweight and obese categories starting at age 15, with no sex difference in those with a normal BMI.\n\nConclusions: In those living with type 1 diabetes, the A1C rise in the teenage years is largely driven by females with a BMI in the overweight and obese categories. Further research is needed to understand the interplay between age, sex, A1C and BMI among children and youth living with type 1 diabetes.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Medicine, Division of Endocrinology, The University of British Columbia Faculty of Medicine, Vancouver, British Columbia, Canada",
    "Vancouver General Hospital, Vancouver, British Columbia, Canada",
    "BC Children’s Hospital Research Institute, Vancouver, British Columbia, Canada",
    "Department of Obstetrics and Gynecology, The University of British Columbia Faculty of Medicine, Vancouver, British Columbia, Canada",
    "Department of Pediatrics, Division of Endocrinology and Diabetes, The University of British Columbia Faculty of Medicine, Vancouver, British Columbia, Canada"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "affs": [
        0,
        1
      ],
      "name": "Joseph MWS Leung",
      "orcid": "0000-0002-3124-3692"
    },
    {
      "affs": [
        2
      ],
      "name": "Melissa Braschel"
    },
    {
      "affs": [
        2,
        3
      ],
      "name": "Jeffrey N Bone",
      "orcid": "0000-0001-7704-1677"
    },
    {
      "affs": [
        2,
        4
      ],
      "name": "Shazhan Amed"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/42f7tkmax73xs.bib",
  "cited_by": 0,
  "doi": "10.1136/bmjopen-2026-122858",
  "fulltext_url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13723844/",
  "id": "42f7tkmax73xs",
  "issns": [
    "2044-6055",
    "2044-6055"
  ],
  "landing_url": "https://bmjopen.bmj.com/lookup/doi/10.1136/bmjopen-2026-122858",
  "language": "en",
  "licence": "CC-BY-NC-4.0",
  "licence_label": "CC BY-NC 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "1506"
    ],
    [
      "heading",
      "1843"
    ],
    [
      "heading",
      "Diabetes and Endocrinology"
    ],
    [
      "heading",
      "Original Research"
    ],
    [
      "openalex",
      "2712|Diabetes Management and Research"
    ]
  ],
  "openalex": "W7223944782",
  "pdf_url": null,
  "pmcid": "PMC13723844",
  "pmid": "42946355",
  "published": "2026-10-27",
  "publisher": "BMJ",
  "ris": "https://research.draconitic.com/paper/42f7tkmax73xs.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:44Z",
      "native_id": "10.1136/bmjopen-2026-122858",
      "source": "crossref",
      "url": "https://bmjopen.bmj.com/lookup/doi/10.1136/bmjopen-2026-122858"
    },
    {
      "first_seen": "2026-11-04T12:22:24Z",
      "native_id": "PMC13723844",
      "source": "pmc",
      "url": "https://doi.org/10.1136/bmjopen-2026-122858"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2712|Diabetes Management and Research",
      "subfield": "endocrinology-metabolism"
    }
  ],
  "title": "Differences in A1C trajectory by sex and BMI in paediatric type 1 diabetes: a retrospective cohort study using a diabetes registry in British Columbia, Canada",
  "title_text": "Differences in A1C trajectory by sex and BMI in paediatric type 1 diabetes: a retrospective cohort study using a diabetes registry in British Columbia, Canada",
  "type": "peer-reviewed",
  "updated_at": "2026-11-05T12:20:35Z",
  "url": "https://research.draconitic.com/paper/42f7tkmax73xs",
  "venue": "BMJ Open",
  "versions": []
}