{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T05:17:43Z","timestamp":1788239863164,"version":"build-2803163510"},"reference-count":25,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T00:00:00Z","timestamp":1787875200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Committee of Science of the Ministry of Science and Higher Education of the Republic of Ka-zakhstan","award":["BR24992814"],"award-info":[{"award-number":["BR24992814"]}]},{"award":["BR24992814"],"award-info":[{"award-number":["BR24992814"]}],"id":[{"id":"https:\/\/ror.org\/05dwvd537","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Background\/Objectives: Metabolic syndrome (MetS) is a major global public health concern associated with an increased risk of cardiovascular disease and type 2 diabetes mellitus. Iron metabolism has been implicated, but the storage (ferritin) and functional (soluble transferrin receptor, sTfR) axes are rarely assessed within a single model. We aimed to determine whether both axes are independently associated with glycaemia and MetS and to evaluate their diagnostic value. Materials and Methods: A cross-sectional study was conducted in 297 adults (72.8% women) from Turkestan, Kazakhstan. Hierarchical regression models with sequential adjustment were applied for age, sex, body mass index (BMI), high-sensitivity C-reactive protein (hs-CRP), dietary inflammatory index (DII), HFE H63D genotype, and gamma-glutamyl transferase (GGT). Path analysis and receiver operating characteristic (ROC) analysis were also performed. Results: Ferritin and sTfR were independently associated with fasting glucose (\u03b2 = 0.27 and 0.73, respectively) and metabolic syndrome (OR = 1.52 and 4.53, respectively). When analyzed separately, neither biomarker reached statistical significance for MetS (ferritin: OR = 1.20, p = 0.140; sTfR: OR = 1.93, p = 0.072). Ferritin demonstrated no discriminatory ability in men (AUC = 0.500, 95% CI 0.370\u20130.630) and modest discrimination in women (AUC = 0.652, 95% CI 0.571\u20130.732). GGT accounted for approximately 28% of the ferritin\u2013glucose association in a path-analytic model. Ferritin, GGT, and HbA1c levels increased progressively even among individuals with 0\u20132 MetS components. Conclusions: Both the storage and functional axes of iron metabolism provide independent information on glycaemic status, but their associations become apparent only when assessed simultaneously. Ferritin alone is not suitable as a diagnostic marker for metabolic syndrome.<\/jats:p>","DOI":"10.3390\/diagnostics16172773","type":"journal-article","created":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T18:33:52Z","timestamp":1787942032000},"page":"2773","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Ferritin and Soluble Transferrin Receptor Beyond Inflammation: Independent Associations with Fasting Glucose and Metabolic Syndrome in a Central Asian Cohort"],"prefix":"10.3390","volume":"16","author":[{"given":"Dana","family":"Kaldarkhan","sequence":"first","affiliation":[{"name":"Faculty of Medicine, Khoja Akhmet Yassawi International Kazakh-Turkish University, Turkestan 160000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9120-8565","authenticated-orcid":false,"given":"Karlygash","family":"Sadykova","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Khoja Akhmet Yassawi International Kazakh-Turkish University, Turkestan 160000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5655-5465","authenticated-orcid":false,"given":"Ainash","family":"Oshibayeva","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Khoja Akhmet Yassawi International Kazakh-Turkish University, Turkestan 160000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2139-3221","authenticated-orcid":false,"given":"Gulnaz","family":"Nuskabayeva","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Khoja Akhmet Yassawi International Kazakh-Turkish University, Turkestan 160000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gulzira","family":"Baimakhanova","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Khoja Akhmet Yassawi International Kazakh-Turkish University, Turkestan 160000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Malika","family":"Raimova","sequence":"additional","affiliation":[{"name":"Department of Neurology and Traditional Medicine, Tashkent State Medical University, Tashkent 100109, Uzbekistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nigora","family":"Alikulova","sequence":"additional","affiliation":[{"name":"Department of Neurology and Traditional Medicine, Tashkent State Medical University, Tashkent 100109, Uzbekistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nodira","family":"Khamidova","sequence":"additional","affiliation":[{"name":"Department of Neurology and Traditional Medicine, Tashkent State Medical University, Tashkent 100109, Uzbekistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shoira","family":"Isanova","sequence":"additional","affiliation":[{"name":"Department of Neurology, Samarkand State Medical University, Samarkand 140103, Uzbekistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8848-0827","authenticated-orcid":false,"given":"Dinara","family":"Azizkhojayeva","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Khoja Akhmet Yassawi International Kazakh-Turkish University, Turkestan 160000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-4263-8157","authenticated-orcid":false,"given":"Ainur","family":"Turmanbayeva","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Khoja Akhmet Yassawi International Kazakh-Turkish University, Turkestan 160000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kanatzhan","family":"Kemelbekov","sequence":"additional","affiliation":[{"name":"Department of Pediatrics-1, South Kazakhstan Medical Academy, Shymkent 160019, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1007\/s11906-018-0812-z","article-title":"The Global Epidemic of the Metabolic Syndrome","volume":"20","author":"Saklayen","year":"2018","journal-title":"Curr. 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