{
  "abstract": "Background Retinol-binding protein 4 (RBP4) has been linked to immune regulation, but whether its associations with type 2 inflammatory biomarkers (eosinophils and immunoglobulin E (IgE)) and pulmonary function differ by sex in asthma remains unknown. Objectives To evaluate the sex-specific associations of serum RBP4 with type 2 inflammatory biomarkers and spirometric indices in adults with asthma. Methods Adults with physician-diagnosed asthma attending a respiratory clinic between January and June 2026 were consecutively enrolled in this cross-sectional study. Associations of serum RBP4 with inflammatory biomarkers and spirometric indices were evaluated using Spearman’s and Pearson’s correlation analyses, as appropriate. Results A total of 88 adults with asthma (35 males and 53 females) were included. Females had a higher body mass index and FEV₁/FVC ratio than males (both P < 0.01), whereas other baseline characteristics were comparable. Serum RBP4 was positively correlated with total IgE in both males (ρ = 0.66, P < 0.01) and females (ρ = 0.53, P < 0.01), but not with peripheral blood eosinophil count in either sex. Serum RBP4 was not associated with FEV₁/FVC or PEF in males or females. A modest inverse correlation between serum RBP4 and FEF₂₅–₇₅ was observed only in males (r = − 0.35, P = 0.03), with no corresponding association in females. Conclusion Serum RBP4 was positively associated with total IgE, but not peripheral blood eosinophils or conventional spirometric indices, although a modest male-specific inverse association with FEF₂₅–₇₅ warrants confirmation in larger prospective studies.",
  "abstract_shown": true,
  "affiliations": [
    "Allergy and Asthma Center, Najaf Health Directorate, Al-Sader Teaching Hospital, Ministry of Health",
    "Medical Physiology Department, College Of Medicine, University of Kufa"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 2,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Rasha AL-Darraji"
    },
    {
      "affs": [
        1
      ],
      "name": "Zahraa Abdulaali Al-Mudhafar"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/b9bdqqjpbadpj.bib",
  "cited_by": 0,
  "doi": "10.1186/s43168-026-00704-2",
  "fulltext_url": "https://doi.org/10.1186/s43168-026-00704-2",
  "id": "b9bdqqjpbadpj",
  "issns": [
    "1687-8426",
    "2314-8551"
  ],
  "landing_url": "https://doi.org/10.1186/s43168-026-00704-2",
  "language": "en",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "lcc",
      "RC705-779"
    ],
    [
      "lcc",
      "RC86-88.9"
    ],
    [
      "openalex",
      "2737|Asthma and respiratory diseases"
    ]
  ],
  "openalex": "W7223127740",
  "pdf_url": "https://link.springer.com/content/pdf/10.1186/s43168-026-00704-2.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-25",
  "publisher": "SpringerOpen",
  "ris": "https://research.draconitic.com/paper/b9bdqqjpbadpj.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T13:45:48Z",
      "native_id": "b8bc688d81f3400eaa883de060395030",
      "source": "doaj",
      "url": "https://doi.org/10.1186/s43168-026-00704-2"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2737|Asthma and respiratory diseases",
      "subfield": "physiology"
    }
  ],
  "title": "Sex-specific associations of serum retinol-binding protein 4 with type 2 inflammatory biomarkers and pulmonary function in adults with asthma",
  "title_text": "Sex-specific associations of serum retinol-binding protein 4 with type 2 inflammatory biomarkers and pulmonary function in adults with asthma",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T13:45:48Z",
  "url": "https://research.draconitic.com/paper/b9bdqqjpbadpj",
  "venue": "The Egyptian Journal of Bronchology",
  "versions": []
}