{
  "abstract": "Background: The C3 epimer of 25-hydroxyvitamin D3 [3-epi-25(OH)D3] can be measured in maternal and umbilical cord circulation, but whether it is related to later neurodevelopment is unknown. Objective: To explore associations between cord 3-epi-25(OH)D3 and parent-reported autism-related trait domains at 10 years in the KLOTHO birth cohort. Methods: This secondary analysis used prospectively collected perinatal samples and 10-year questionnaire data. Vitamin D metabolites were quantified by liquid chromatography–tandem mass spectrometry with epimer separation. The Australian Scale for Asperger’s Syndrome was used dimensionally, not diagnostically. Spearman correlations, false-discovery-rate (FDR) correction across 13 unique bivariate comparisons, supportive linear regressions, sex-stratified analyses, and a stricter record-linkage sensitivity analysis were conducted. Results: Data were available for 87 offspring (41 boys and 46 girls). Cord 3-epi-25(OH)D3 was inversely associated with cognitive-domain score (Spearman ρ = −0.412; p < 0.001; Benjamini–Hochberg q = 0.001). The crude regression estimate was also inverse (B = −0.285; 95% CI, −0.458 to −0.112; p = 0.002), but the association attenuated after covariate adjustment and all adjusted confidence intervals included the null. A stricter linkage analysis remained significant (n = 84; ρ = −0.350; p = 0.001). The correlation was numerically stronger in boys than girls, but the between-sex comparison was not significant (p = 0.075). A positive correlation was also observed for social and emotional traits (ρ = 0.302; q = 0.023), indicating inconsistent directions across domains; the tertile analysis was non-significant. Conclusions: Cord 3-epi-25(OH)D3 was associated with lower cognitive-domain scores in unadjusted rank analyses, but the lack of stable adjusted linear evidence, inconsistent domain pattern, and small sample restrict interpretation. These findings are hypothesis-generating and do not imply causality, sex-specific effects, or clinical utility.",
  "abstract_shown": true,
  "affiliations": [
    "Laboratory of Pharmacology, Medical School, Aristotle University, 54124 Thessaloniki, Greece",
    "Unit of Reproductive Endocrinology, 1st Department of Obstetrics and Gynecology, Medical School, Faculty of Health Sciences, Aristotle University, 54124 Thessaloniki, Greece",
    "Department of Biological Chemistry, National and Kapodistrian University of Athens, 15771 Athens, Greece",
    "Assisting Nature Centre of Reproduction and Genetics, 57001 Thessaloniki, Greece",
    "Medical School, Aristotle University, 54124 Thessaloniki, Greece",
    "Department of Midwifery, Faculty of Health and Caring Sciences, University of West Attica, 12243 Athens, Greece",
    "Second Department of Surgery, Medical School, Aretaieio Athens Hospital, National and Kapodistrian University of Athens, 11528 Athens, Greece",
    "Thermi Clinic, 57001 Thessaloniki, Greece"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 11,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Spyridon N. Karras",
      "orcid": "0000-0002-4225-2746"
    },
    {
      "affs": [
        1
      ],
      "name": "Dimitrios G. Goulis",
      "orcid": "0000-0002-5005-1995"
    },
    {
      "affs": [
        2
      ],
      "name": "Maria Dalamaga",
      "orcid": "0000-0002-7008-388X"
    },
    {
      "affs": [
        3
      ],
      "name": "Maria Kypraiou"
    },
    {
      "affs": [
        4
      ],
      "name": "Antonios Vlastos",
      "orcid": "0000-0001-6901-744X"
    },
    {
      "affs": [
        4
      ],
      "name": "Marios Anemoulis",
      "orcid": "0000-0002-5804-4669"
    },
    {
      "affs": [
        5
      ],
      "name": "Vikentia Harizopoulou",
      "orcid": "0009-0001-6004-1205"
    },
    {
      "affs": [
        6
      ],
      "name": "Georgios Mastorakos",
      "orcid": "0000-0002-1929-3275"
    },
    {
      "affs": [
        7
      ],
      "name": "Dimitrios Skoutas"
    },
    {
      "affs": [
        0
      ],
      "name": "Stergios A. Polyzos",
      "orcid": "0000-0001-9232-4042"
    },
    {
      "affs": [
        0
      ],
      "name": "Antonios Goulas"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/1qz7gnkasva09.bib",
  "cited_by": 0,
  "doi": "10.3390/nu18203361",
  "fulltext_url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13708172/?tool=EBI",
  "id": "1qz7gnkasva09",
  "issns": [
    "2072-6643"
  ],
  "landing_url": "https://www.mdpi.com/2072-6643/18/20/3361",
  "language": "eng",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2734|Vitamin D Research Studies"
    ]
  ],
  "openalex": "W7220977598",
  "pdf_url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13708172/pdf/?tool=EBI",
  "pmcid": "PMC13708172",
  "pmid": null,
  "published": "2026-10-01",
  "publisher": "MDPI AG",
  "ris": "https://research.draconitic.com/paper/1qz7gnkasva09.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:56Z",
      "native_id": "10.3390/nu18203361",
      "source": "crossref",
      "url": "https://www.mdpi.com/2072-6643/18/20/3361"
    },
    {
      "first_seen": "2026-10-30T12:21:49Z",
      "native_id": "PMC:PMC13708172",
      "source": "europepmc",
      "url": "https://europepmc.org/article/PMC/PMC13708172"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "issn:2072-6643",
      "subfield": "nutrition"
    }
  ],
  "title": "Cord Blood 3-Epi-25-Hydroxyvitamin D3 and Autism-Related Cognitive Traits at Age 10 Years: An Exploratory Secondary Analysis of the KLOTHO Birth Cohort",
  "title_text": "Cord Blood 3-Epi-25-Hydroxyvitamin D3 and Autism-Related Cognitive Traits at Age 10 Years: An Exploratory Secondary Analysis of the KLOTHO Birth Cohort",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:21:49Z",
  "url": "https://research.draconitic.com/paper/1qz7gnkasva09",
  "venue": "Nutrients",
  "versions": []
}