{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T15:53:16Z","timestamp":1787932396398,"version":"build-2784847793"},"reference-count":66,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2024,7,14]],"date-time":"2024-07-14T00:00:00Z","timestamp":1720915200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"\u201cIuliu Ha\u021bieganu\u201d University of Medicine and Pharmacy Cluj-Napoca, Romania"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>An adequate vitamin D level is essential for optimal bone mass formation during growth. The present study aimed to assess (i) the sex-specific, age-specific, and potential seasonal (spring, summer, winter) influences on the pediatric circulating levels of 25-hydroxyvitamin D (25(OH)D); (ii) determine the frequency of pediatric patients with vitamin D deficiency (VDD) or insufficiency (VDI); and (iii) quantify the association between age category, sex, and season types and susceptibility to VDD and VDI, respectively. Laboratory data were collected on serum 25(OH)D levels in children aged between 2 and 18 years (n = 1674) who underwent blood sampling following admission to a university pediatric hospital in Cluj-Napoca (Romania) between January and June 2023. VDD (&lt;20 ng\/mL) was observed in 27% of pediatric patients. Among toddlers and preschoolers (2\u20135 years), VDD was 11%, while it was 33% among school-aged children (6\u201311 years) and 39% among adolescents (12\u201318 years). We found a significant difference in the frequencies of vitamin D status between females and males (p = 0.006). Also, we found significant associations of vitamin D status with age categories (p &lt; 0.0001) and seasonal variations (p = 0.03). After adjusting for season of blood collection, the multinomial logistic regression model showed that children aged 6\u201311 years old (adjusted OR = 7, 95% CI: (4.9, 9.4)), children aged 12\u201318 years old (adjusted OR = 14, 95% CI: (9.3, 19.6)), and females (adjusted OR = 1.43, 95% CI: (1.10, 1.86)) were significantly associated with higher odds of VDD. In conclusion, the study revealed a significant difference in the frequency of VDD and VDI among pediatric patients older than six years, with a significant difference according to sex and season, being more pronounced among girls and during the winter and spring seasons.<\/jats:p>","DOI":"10.3390\/nu16142266","type":"journal-article","created":{"date-parts":[[2024,7,15]],"date-time":"2024-07-15T08:35:17Z","timestamp":1721032517000},"page":"2266","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Vitamin D Status among 2\u201318-Year-Old Romanian Pediatric Patients: A Single-Center Study"],"prefix":"10.3390","volume":"16","author":[{"given":"Ioana","family":"Badiu Ti\u0219a","sequence":"first","affiliation":[{"name":"Department of Mother and Child Care, \u201cIuliu Ha\u021bieganu\u201d University of Medicine and Pharmacy, 2-4 C\u00e2mpeni Street, 400217 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4381-5544","authenticated-orcid":false,"given":"Anamaria","family":"Cozma-Petru\u021b","sequence":"additional","affiliation":[{"name":"Department of Bromatology, Hygiene, Nutrition, \u201cIuliu Ha\u021bieganu\u201d University of Medicine and Pharmacy, 6 Pasteur Street, 400349 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7645-0716","authenticated-orcid":false,"given":"Gabriel","family":"Sama\u0219ca","sequence":"additional","affiliation":[{"name":"Department of Functional Biosciences, Immunology and Allergology, \u201cIuliu Ha\u021bieganu\u201d University of Medicine and Pharmacy, 19-21 Croitorilor Street, 400162 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5029-5060","authenticated-orcid":false,"given":"Doina","family":"Miere","sequence":"additional","affiliation":[{"name":"Department of Bromatology, Hygiene, Nutrition, \u201cIuliu Ha\u021bieganu\u201d University of Medicine and Pharmacy, 6 Pasteur Street, 400349 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9469-3546","authenticated-orcid":false,"given":"Lorena","family":"Filip","sequence":"additional","affiliation":[{"name":"Department of Bromatology, Hygiene, Nutrition, \u201cIuliu Ha\u021bieganu\u201d University of Medicine and Pharmacy, 6 Pasteur Street, 400349 Cluj-Napoca, Romania"},{"name":"Academy of Romanian Scientists (AOSR), 3 Ilfov Street, 050044 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6808-5723","authenticated-orcid":false,"given":"Roxana","family":"Banc","sequence":"additional","affiliation":[{"name":"Department of Bromatology, Hygiene, Nutrition, \u201cIuliu Ha\u021bieganu\u201d University of Medicine and Pharmacy, 6 Pasteur Street, 400349 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3771-9003","authenticated-orcid":false,"given":"Oana","family":"M\u00eerza","sequence":"additional","affiliation":[{"name":"Department of Bromatology, Hygiene, Nutrition, \u201cIuliu Ha\u021bieganu\u201d University of Medicine and Pharmacy, 6 Pasteur Street, 400349 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4557-5364","authenticated-orcid":false,"given":"Mihaela","family":"Iancu","sequence":"additional","affiliation":[{"name":"Department of Medical Informatics and Biostatistics, \u201cIuliu Ha\u021bieganu\u201d University of Medicine and Pharmacy, 6 Pasteur Street, 400349 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,7,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"331","DOI":"10.4161\/derm.26738","article-title":"Vitamin D: Update 2013: From rickets prophylaxis to general preventive healthcare","volume":"5","author":"Spitz","year":"2013","journal-title":"Derm. 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