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Search Results (232)

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Keywords = hypovitaminosis D

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14 pages, 824 KB  
Article
Treatment of Hypovitaminosis D Is Associated with Improvement in Anemia of Inflammation in Patients with Decompensated Cirrhosis
by Raquel Diaz-Ruiz, Maria Poca, Eva Roman, Berta Cuyàs, Irene Breton, Rafael Bañares, German Soriano and Rita Garcia-Martinez
Med. Sci. 2026, 14(2), 267; https://doi.org/10.3390/medsci14020267 - 21 May 2026
Viewed by 129
Abstract
Background/Objectives: Anemia of inflammation (AI) is a prevalent condition linked to systemic inflammation in several chronic diseases, including chronic liver diseases. Hypovitaminosis D is frequently identified in patients with chronic diseases, and its pathogenic role in anemia is currently under investigation. The [...] Read more.
Background/Objectives: Anemia of inflammation (AI) is a prevalent condition linked to systemic inflammation in several chronic diseases, including chronic liver diseases. Hypovitaminosis D is frequently identified in patients with chronic diseases, and its pathogenic role in anemia is currently under investigation. The aim of this study was to prospectively investigate changes in hemoglobin concentration and inflammatory markers in vitamin D-deficient/-insufficient patients with decompensated cirrhosis after initiating vitamin D supplementation, in addition to the supplementation of other micronutrients if needed. Methods: Patients with cirrhosis discharged from decompensation were assessed at baseline and 3 months after vitamin D supplementation. Laboratory parameters of red cell series, nutrition, and micronutrients were assessed in both visits, together with markers of systemic inflammation. Results: Thirty-nine patients were included in the study, of whom 33 completed the 3-month evaluation and were analyzed [age: 62.7 ± 10.7 years; gender: n = 29 (87.9%) males; Charlson index: 5.9 ± 1.6; Model for End-Stage Liver Disease (MELD): 12.4 ± 4.5; baseline hemoglobin (Hb): 11.7 ± 1.8 g/dL (anemia n = 24 (72.7%)); mean 25-hydroxyvitamin D (25OHD) plasma level: 15.5 ± 8.6 µg/L]. A significant increase in plasma 25OHD (40.1 ± 17.8, p < 0.001) and in Hb (12.4 ± 2.0, p = 0.01) was observed at 3 months with a decrease in the prevalence of anemia (n = 17, p = 0.015) and of Interleukin 6 in plasma levels [IL-6, 10.7 (5.8–23.3) vs. 6.5 (4.1–11.8), p = 0.016]. A greater rise in hemoglobin was correlated with higher plasma IL-6 concentration at baseline. Milder anemia and indexes of hypoferremia at baseline, along with optimal renal function and plasma levels of 25OHD at 3 months, were linked to resolution of anemia. Conclusions: Treating vitamin D deficiency together with other micronutrient deficits is associated with inflammation amelioration and improvement in anemia in patients with cirrhosis following discharge from acute decompensation. This paper supports the potential role of vitamin D in the management of anemia in patients with decompensated cirrhosis by modulating systemic inflammation. Full article
(This article belongs to the Section Hepatic and Gastroenterology Diseases)
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16 pages, 915 KB  
Article
Update on Vitamin D Status and Seasonal Variation in a Non-Supplemented Population Living in a High Polluted Urban Area—A Cross-Sectional Study
by Francesco Bertoldo, Renata Bortolus, Francesca Filippini, Francesca Chiaffarino, Silvia Udali, Monica Rizzi, Rachele Montemezzi, Giorgio Gandini, Martina Montagnana, Giuseppe Lippi, Sara Moruzzi, Fabio Parazzini, Nicola Martinelli, Matteo Lombini, Sergio De Marchi, Francesca Pizzolo and Simonetta Friso
Nutrients 2026, 18(10), 1614; https://doi.org/10.3390/nu18101614 - 20 May 2026
Viewed by 207
Abstract
Background: Serum concentrations of 25-hydroxyvitamin D [25(OH)D] are associated with the risk of several chronic and acute diseases. However, updated data on vitamin D status in Mediterranean countries, including Italy, remain limited, hindering effective public health strategies. Objective: To assess serum 25(OH)D levels [...] Read more.
Background: Serum concentrations of 25-hydroxyvitamin D [25(OH)D] are associated with the risk of several chronic and acute diseases. However, updated data on vitamin D status in Mediterranean countries, including Italy, remain limited, hindering effective public health strategies. Objective: To assess serum 25(OH)D levels and their seasonal variation in healthy blood donors aged 18–65 years living in Northern Italy and not taking vitamin D supplements. Given the latitude and the high levels of environmental pollution, cutaneous vitamin D synthesis may be impaired in this population. Recent Italian guidelines on supplementation emphasize the need for updated data on the prevalence of hypovitaminosis D and seasonal variation in endogenous vitamin D synthesis. Methods: In this exploratory retrospective cross-sectional study, 534 blood donors (268 men and 266 women) attending the Transfusion Medicine Unit of the Verona University Hospital were enrolled between April 2016 and May 2018. Serum 25(OH)D concentrations were analyzed by season. Clinical, lifestyle, pharmacological and dietary characteristics were also collected. Results: Among healthy, normal-weight individuals, the prevalence of vitamin D insufficiency (25(OH)D < 50 nmol/L) was low and limited to one-two months per year. Overweight and obesity significantly reduced the likelihood of achieving adequate 25(OH)D levels through cutaneous synthesis for several months. Mean 25(OH)D concentrations were higher than those previously reported in the same area, while seasonal variation remained preserved. Conclusions: In a relatively small non-supplemented population of blood donors living in a high polluted urban area of Northern Italy, seasonal vitamin D synthesis seems to be preserved. These updated data show higher 25(OH)D levels compared to past findings. Although these data certainly warrant further validation through a national survey involving other regions of Italy and in not selected population, they appear to be in line with the SIOMMMS recommendations against indiscriminate serum 25(OH)D testing and against routine supplementation for healthy normal-weight individuals under 70 years. Full article
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13 pages, 553 KB  
Article
Association of Vitamin D Receptor Gene Polymorphisms and Hypovitaminosis D with Reduced Bone Mineral Density in Survivors of Childhood Leukemia: A Study in Algerian Patients
by Wafa Khelaifia, Ines Gouaref, Fatma Zohra Djaballah-Ider, Nabila Bouterfas, Chafia Touil-Boukoffa and Assia Galleze
Curr. Issues Mol. Biol. 2026, 48(5), 506; https://doi.org/10.3390/cimb48050506 - 14 May 2026
Viewed by 178
Abstract
Survivors of childhood leukemia are at increased risk of long-term skeletal complications, including reduced bone mineral density (BMD). Vitamin D deficiency and genetic variations in the vitamin D receptor (VDR) gene are important factors influencing bone health, yet their combined effects remain insufficiently [...] Read more.
Survivors of childhood leukemia are at increased risk of long-term skeletal complications, including reduced bone mineral density (BMD). Vitamin D deficiency and genetic variations in the vitamin D receptor (VDR) gene are important factors influencing bone health, yet their combined effects remain insufficiently studied, particularly in North African populations. This case-control study included 130 survivors of childhood acute lymphoblastic leukemia (ALL) in remission (age range: 5–26 years) and 110 age- and sex-matched healthy controls recruited from Beni Messous Hospital. BMD was assessed at the lumbar spine and femoral neck using dual-energy X-ray absorptiometry and expressed as z-scores. Serum 25-hydroxyvitamin D levels were measured, and VDR polymorphisms (FokI, ApaI, and BsmI) were analyzed using PCR-RFLP. Hypovitaminosis D was observed in 43.85% of patients at diagnosis and 23.07% after remission. Survivors had significantly lower BMD compared with controls at both the lumbar spine (z-score: −4.26 ± 0.75 vs. 0 ± 1, p < 0.001) and femoral neck (−3.78 ± 0.45 vs. 0 ± 1, p < 0.001). Reduced BMD for age was identified in 30% of patients. Variant genotypes TT (FokI), AA (BsmI), and CC (ApaI) were more frequent in patients and were associated with lower BMD (p < 0.0001). These findings suggest that hypovitaminosis D and VDR polymorphisms may be associated with bone health in survivors of childhood leukemia. The coexistence of these factors may contribute to interindividual variability in BMD. Full article
(This article belongs to the Section Molecular Medicine)
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13 pages, 289 KB  
Article
Vitamin D Deficiency in Institutionalized Older Adults: Associations with Supplementation Practices but Not with Cognitive Decline or Dementia
by Larissa David Soares, Myrella Teixeira Rosales, Bruna Costa Silveira, Alice Moreira Rizzolli, Caroline Helen Santos Gonçalves Mazala, Isabela Thurow Lemes, Fabiana Da Silveira Santos Sinnott, Thiago Falson Santana, Érica Paiva Espinosa, Eduarda Neutzling Drawanz, Ana Beatriz Gonçalves Araújo, Nathalia Passos Moura, Aline Longoni, Diogo Onofre Souza, Maria Noel Marzano Rodrigues and Adriano Martimbianco De Assis
Nutrients 2026, 18(7), 1078; https://doi.org/10.3390/nu18071078 - 27 Mar 2026
Viewed by 650
Abstract
Background/Objectives: Population aging has been accompanied by increased institutionalization of older adults and a high prevalence of vitamin D deficiency in this group. Although the literature suggests a possible relationship between vitamin D and cognition, findings remain inconsistent, particularly in institutional settings. This [...] Read more.
Background/Objectives: Population aging has been accompanied by increased institutionalization of older adults and a high prevalence of vitamin D deficiency in this group. Although the literature suggests a possible relationship between vitamin D and cognition, findings remain inconsistent, particularly in institutional settings. This cross-sectional study aimed to investigate factors associated with vitamin D deficiency in institutionalized older adults, emphasizing the role of vitamin D supplementation and length of institutionalization, as well as to evaluate the association between serum vitamin D levels, cognitive decline, and dementia. Methods: A total of 104 older adults living in different long-term care institutions (LTCFs) in the city of Pelotas, RS, Brazil, were evaluated. Sociodemographic, clinical, and nutritional data were collected via interviews and medical record review. Serum 25-hydroxyvitamin D levels were categorized according to the Institute of Medicine cutoffs (<20 ng/mL and ≥20 ng/mL). Cognitive decline was assessed using the Mini-Mental State Examination, and dementia was evaluated with the Clinical Dementia Rating scale. Analyses included bivariate tests and binary logistic regression. Results: A high prevalence of vitamin D deficiency (52.9%), cognitive decline (83.6%), and questionable or mild dementia (79.4%) was observed. In multivariate analysis, vitamin D supplementation remained independently associated with vitamin D deficiency, whereas no significant association was observed between vitamin D levels and cognitive decline or dementia. Conclusions: Vitamin D deficiency in institutionalized older adults is predominantly associated with contextual and care-related factors rather than cognitive impairment, highlighting the importance of systematic nutritional monitoring and vitamin D supplementation strategies in institutional settings. Full article
13 pages, 2964 KB  
Article
Vitamin D Deficiency Activates Gdnf-Ret-pErk1/2 Signal and Induces Kidney Malformations in Mice
by Minghui Yu, Ningli Ye, Haixin Ju, Qianfan Miao, Chunyan Wang, Rufeng Dai, Jing Chen, Yihui Zhai, Lei Sun, Xiaohui Wu, Hong Xu and Qian Shen
Int. J. Mol. Sci. 2026, 27(7), 3042; https://doi.org/10.3390/ijms27073042 - 27 Mar 2026
Viewed by 485
Abstract
Congenital anomalies of the kidney and urinary tract (CAKUT) constitute the most common underlying cause of chronic kidney disease in pediatric populations. Maternal hypovitaminosis D links to mesoderm-related birth defects, leading to our hypothesis that maternal vitamin D deficiency (VDD) impairs renal development [...] Read more.
Congenital anomalies of the kidney and urinary tract (CAKUT) constitute the most common underlying cause of chronic kidney disease in pediatric populations. Maternal hypovitaminosis D links to mesoderm-related birth defects, leading to our hypothesis that maternal vitamin D deficiency (VDD) impairs renal development (a mesoderm-derived process) and induces offspring CAKUT. To investigate whether a low-vitamin D level can cause CAKUT, we used vitamin D-free diets to induce a maternal vitamin D deficiency mice model. The maternal vitamin D deficiency (VDD) mice models and normal vitamin D status (CON) were successfully established by administering a vitamin D-free or vitamin D-sufficient diet for 4 weeks prior to pregnancy. The overall incidence of CAKUT was significantly increased in VDD neonatal mice (19.4% vs. 2.44%; p = 0.0006), with a higher incidence of early duplicated budding in E11.5. E11.5 ureteric bud tissue revealed significantly increased activity of Gdnf-Ret-p-Erk1/2 signaling in the VDD group. In vivo intervention with the p-Erk1/2 antagonist U0126 in the pregnant VDD mice model at E10.5 improved CAKUT occurrence in offspring with p-Erk1/2 expression decreasing toward normal levels. Early metanephric ureteric bud H3K4me3 CUT&TAG analysis at E12.5 revealed chromatin activation patterns, which revealed that the downregulation of Hnf1β promoter region peaks was accompanied by reduced Hnf1β expression, and Robo2 promoter region peak was upregulated with increased Robo2 expression in the VDD group. Maternal vitamin D deficiency in mice significantly increased offspring CAKUT incidence. This phenotype was mediated by enhanced Gdnf-Ret-p-Erk1/2 signaling and reversed by p-Erk1/2 inhibition, with VDD inducing epigenetic remodeling of Hnf1β and Robo2 promoters. Full article
(This article belongs to the Special Issue Regulatory Mechanisms in Kidney Development and Function)
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20 pages, 3217 KB  
Review
Investigating the Inflammatory Link Between Vitamin D and Hidradenitis Suppurativa: A Systematic Review and Causal Inference Analysis
by Jasmine Spiteri, Laura Grech, Dillon Mintoff and Nikolai P. Pace
Int. J. Mol. Sci. 2026, 27(6), 2895; https://doi.org/10.3390/ijms27062895 - 23 Mar 2026
Viewed by 1067
Abstract
An inverse correlation between serum vitamin D levels and hidradenitis suppurativa (HS) severity is frequently reported, yet the causal nature and direction of this association remain unresolved. A systematic review was conducted following PRISMA guidelines, identifying 12 relevant studies. A two-sample Mendelian randomization [...] Read more.
An inverse correlation between serum vitamin D levels and hidradenitis suppurativa (HS) severity is frequently reported, yet the causal nature and direction of this association remain unresolved. A systematic review was conducted following PRISMA guidelines, identifying 12 relevant studies. A two-sample Mendelian randomization (MR) analysis using the inverse-variance weighted (IVW) method was subsequently performed using genetic instruments for vitamin D from the UK Biobank (n = 417,580) and HS summary statistics from FinnGen (n = 1420). The systematic review confirmed a high prevalence of vitamin D deficiency (<20 ng mL−1) among HS patients (weighted mean 17.90 ng mL−1) and identified inverse correlations between vitamin D levels and disease severity, active lesions, and C-reactive protein (CRP), while supplementation improved clinical outcomes. A null MR estimate consistent with the absence of a detectable average linear causal effect of lifelong genetically predicted 25(OH)D levels on HS risk in the analyzed population was observed. Sensitivity analyses yielded consistent null results with no significant horizontal pleiotropy. The results suggest that hypovitaminosis D is likely a marker of the systemic inflammatory state rather than a direct causative factor. The observed clinical benefits of vitamin D supplementation warrant further interventional studies to define its potential therapeutic role. Full article
(This article belongs to the Special Issue Advances in Genetic and Epigenetic Research in Skin Diseases)
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16 pages, 1765 KB  
Article
Associations Between Serum 25(OH)D Concentrations and Clinical Characteristics in Pediatric Patients
by Maria Nicolae, Sorin Deacu, Cristina Maria Mihai, Tatiana Chisnoiu, Irina Ion, Claudia Simona Cambrea, Andreea Nelson Twakor, Alexandra Herlo and Oana Cristina Arghir
Reports 2026, 9(1), 54; https://doi.org/10.3390/reports9010054 - 9 Feb 2026
Viewed by 561
Abstract
Background/Objectives: Vitamin D has an essential role in immune modulation and inflammatory control, particularly in respiratory infections. Despite widespread supplementation policies, hypovitaminosis D remains common in children and data linking vitamin D status to hospitalization outcomes in pediatric upper respiratory tract infections are [...] Read more.
Background/Objectives: Vitamin D has an essential role in immune modulation and inflammatory control, particularly in respiratory infections. Despite widespread supplementation policies, hypovitaminosis D remains common in children and data linking vitamin D status to hospitalization outcomes in pediatric upper respiratory tract infections are limited, especially in Eastern Europe. Methods: We included 400 pediatric patients hospitalized between October 2020 and December 2024 for acute respiratory tract infections (ARTI), and we stratified them into a Normal Vitamin D group (NVD) with sufficient serum 25(OH)D concentrations and a Low Vitamin D group (LVD) with insufficient or deficient levels. Between-group comparisons for continuous variables were performed using non-parametric methods. Results: Children with insufficient or deficient 25(OH)D had a significantly longer duration of hospitalization compared with those with sufficient levels (mean 4.68 ± 2.59 days vs. 2.89 ± 1.81 days). The LVD group showed markedly lower serum vitamin D concentrations (mean 21.63 ± 5.56 ng/mL; median 22.29 ng/mL) compared with the NVD group (mean 47.60 ± 19.59 ng/mL; median 43.70 ng/mL). Markers of disease severity were consistently higher in vitamin D-deficient patients, including higher clinical scores (mean 3.77 ± 2.29 vs. 1.62 ± 1.89), elevated CRP levels (mean 3.50 ± 3.02 mg/L vs. 1.64 ± 1.59 mg/L), and increased O2 therapy requirement (69.5% vs. 21.0%). Fever was more frequent in the LVD group (61.0% vs. 32.0%). An inverse correlation was observed between serum 25(OH)D concentrations and hospitalization duration, clinical score, and disease severity, with deficiency present across all age strata in the LVD group, while no cases of deficiency were observed in the NVD group. Conclusions: Low serum 25(OH)D concentrations are associated with increased disease severity and prolonged hospitalization. Full article
(This article belongs to the Section Paediatrics)
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14 pages, 3357 KB  
Article
Association Among Serum Vitamin D Levels, Visual Field Alterations, and Optical Coherence Tomography Parameters: A Clinical Correlation Study
by Tudor-Corneliu Tarași, Mihaela-Madalina Timofte-Zorila, Filippo Lixi, Mario Troisi, Giuseppe Giannaccare, Luminița Apostu, Ecaterina Anisie, Livio Vitiello and Daniel-Constantin Brănișteanu
Life 2026, 16(1), 85; https://doi.org/10.3390/life16010085 - 6 Jan 2026
Viewed by 835
Abstract
Vitamin D deficiency is increasingly recognized as a systemic factor influencing retinal health through inflammatory, neuroprotective, and vasculotropic pathways. Evidence regarding early retinal alterations in otherwise healthy adults remains limited. This cross-sectional study evaluated 120 eyes from 60 healthy adults stratified by serum [...] Read more.
Vitamin D deficiency is increasingly recognized as a systemic factor influencing retinal health through inflammatory, neuroprotective, and vasculotropic pathways. Evidence regarding early retinal alterations in otherwise healthy adults remains limited. This cross-sectional study evaluated 120 eyes from 60 healthy adults stratified by serum 25(OH)D levels into <30 ng/mL (n = 60) and ≥30 ng/mL (n = 60). All subjects underwent optical coherence tomography (OCT), OCT angiography (OCTA), visual field testing, and contrast sensitivity assessment. Central macular thickness (CMT), ganglion cell complex (GCC) thickness, and perfusion density in the superficial and deep capillary plexuses (SCP, DCP) were compared between groups. Vitamin-D-insufficient eyes showed significantly reduced CMT (267.66 ± 13.31 µm vs. 274.69 ± 14.96 µm; p = 0.035). GCC thinning was significant only in the inner inferior nasal sector (70.7 ± 13.14 µm vs. 76.45 ± 12.12 µm; p = 0.030), whereas other GCC sectors were comparable between groups. Perfusion density was lower in the DCP across whole, inner, and outer regions (all p < 0.001) and in the SCP inner (p = 0.027) and outer (p = 0.009) regions, while whole SCP did not differ (p = 0.065). FAZ area was numerically larger in vitamin-D-insufficient eyes but was not statistically different (p = 0.168). Functionally, retinal sensitivity decline was greater in vitamin-D-insufficient eyes (−2.89 ± 1.29 dB vs. −2.16 ± 1.04 dB; p = 0.003), and mean central sensitivity was lower (p = 0.010), whereas contrast sensitivity did not differ between groups. Serum vitamin D levels < 30 ng/mL are associated with early, subclinical, structural and microvascular retinal alterations in healthy adults, supporting a potential role of hypovitaminosis D as a modifier of retinal integrity. Full article
(This article belongs to the Section Medical Research)
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12 pages, 1332 KB  
Article
Analytical Evaluation of the Autobio 25-OH Vitamin D Assay: Comparison with Liquid Chromatography–Tandem Mass Spectrometry and Clinical Implications
by Flaminia Tomassetti, Eleonora Nicolai, Martina Pelagalli, Federico Cortese, Alfredo Giovannelli, Sabrina Ballerini, Alessia Mozzi, Anastasia De Luca, Massimo Pieri and Sergio Bernardini
Metabolites 2025, 15(12), 802; https://doi.org/10.3390/metabo15120802 - 18 Dec 2025
Viewed by 818
Abstract
Background: 25-Hydroxy vitamin D [25(OH)D] is the circulating form of vitamin D. Its deficiency is a major global health concern, affecting over one billion people. Beyond its role in bone health, low vitamin D levels have been implicated in a wide range of [...] Read more.
Background: 25-Hydroxy vitamin D [25(OH)D] is the circulating form of vitamin D. Its deficiency is a major global health concern, affecting over one billion people. Beyond its role in bone health, low vitamin D levels have been implicated in a wide range of chronic and inflammatory diseases, including diabetes, chronic kidney disease, and cancer. While immunoassays are widely used in routine testing, liquid chromatography–tandem mass spectrometry (LC-MS/MS) remains the reference method for its superior accuracy. This study aimed to evaluate the analytical performance of the Autobio 25(OH)D chemiluminescence assay (Autobio Diagnostics, Zhengzhou, China) compared with LC-MS/MS (Chromsystems Instruments & Chemicals GmbH, Gräfelfing, Germany) and the Siemens chemiluminescent microparticle immunoassay (Siemens HealthCare, Erlangen, Germany). Additionally, the influence of age and sex on 25(OH)D concentrations was examined to explore potential demographic and pathophysiological variations. Methods: 200 residual serum samples were analyzed to compare all three methods. Precision and linearity were verified. Statistical analysis was performed. Results: The Autobio assay showed good correlation with LC-MS/MS (R2 = 0.953; p < 0.001), with acceptable bias and precision (CV < 10%) and confirmed linearity. Age- and sex-related differences were observed, indicating demographic influences on vitamin D status. Conclusions: Accurate and accessible laboratory testing for 25(OH)D is therefore essential for both disease prevention and clinical management. The Autobio 25(OH)D assay demonstrated strong correlation with LC-MS/MS and high analytical reliability. Its good performance makes it a valuable tool for routine assessment of 25(OH)D and for supporting the early detection or monitoring of hypovitaminosis D in clinical practice. Full article
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13 pages, 2442 KB  
Article
Prevalence of Vitamin D Hypovitaminosis in Croatia: A Cross-Sectional Study Based on Routine Clinical Examinations
by Jelena Kelemen, Luka Bulić, Petar Brlek, Renata Zadro, Jelena Pavlović, Marin Vučić, Eva Brenner and Dragan Primorac
Nutrients 2025, 17(24), 3863; https://doi.org/10.3390/nu17243863 - 11 Dec 2025
Cited by 1 | Viewed by 1387
Abstract
Background/Objectives: Vitamin D deficiency is recognized as a global public health concern due to its implications for bone health, immune regulation, and chronic disease risk. Despite its significance, comprehensive data on the prevalence of hypovitaminosis D in the Croatian population remain limited. [...] Read more.
Background/Objectives: Vitamin D deficiency is recognized as a global public health concern due to its implications for bone health, immune regulation, and chronic disease risk. Despite its significance, comprehensive data on the prevalence of hypovitaminosis D in the Croatian population remain limited. This study aimed to determine the distribution of 25-hydroxyvitamin D (25-OH D) levels in a group of patients who underwent routine clinical examination, evaluate the prevalence of deficiency, and assess potential associations with demographic factors such as age and sex. Methods: This cross-sectional study included 829 individuals aged 19–85 years who underwent routine clinical testing at our institution. Serum 25-OH D concentrations were measured and classified as normal (≥75 nmol/L), deficient (<75 nmol/L, ≥50 nmol/L), or severely deficient (<50 nmol/L). Data on age and sex were extracted, and statistical analyses included descriptive statistics, tests for normality (Kolmogorov–Smirnov), comparisons (Mann–Whitney U, Kruskal–Wallis), and correlation testing (Spearman’s rho). Significance was set at p < 0.05. Results: The cohort consisted of 525 females (63.3%) and 304 males (36.7%), with a mean age of 49.2 ± 15.8 years. The mean and median serum 25-OH D concentrations were 53.5 and 53.0 nmol/L, respectively (IQR: 40.0–65.0). Severe deficiency (<50 nmol/L) was present in 43.7% of participants, while an additional 49.2% exhibited moderate deficiency, leaving only 7.1% with sufficient levels. No statistically significant differences in vitamin D levels were observed between sexes, nor was there a significant correlation between age and vitamin D concentration (p > 0.05). Conclusions: Vitamin D deficiency is highly prevalent in the Croatian population, with more than 90% of individuals showing suboptimal serum levels. The absence of significant associations with age or sex suggests a widespread deficiency pattern, underscoring the need for nationwide preventive strategies, including dietary supplementation and public health education initiatives to improve vitamin D status. Full article
(This article belongs to the Special Issue Prevalence and Risk Factors of Vitamin D Deficiency)
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12 pages, 243 KB  
Article
Maternal Vitamin D Status, Gestational Hypertension, and Preeclampsia: A Cross-Sectional Study in Urban Greece
by Artemisia Kokkinari, Kleanthi Gourounti, Maria Dagla, Nikoleta Tsinisizeli and Georgios Iatrakis
Biomedicines 2025, 13(11), 2624; https://doi.org/10.3390/biomedicines13112624 - 27 Oct 2025
Viewed by 1830
Abstract
Background: Evidence linking maternal vitamin D status with gestational hypertensive disorders and neonatal outcomes in Southern Europe remains limited. We evaluated maternal and cord 25-hydroxyvitamin D [25(OH)D] at birth in an urban Greek cohort and examined associations with gestational hypertension and preeclampsia. [...] Read more.
Background: Evidence linking maternal vitamin D status with gestational hypertensive disorders and neonatal outcomes in Southern Europe remains limited. We evaluated maternal and cord 25-hydroxyvitamin D [25(OH)D] at birth in an urban Greek cohort and examined associations with gestational hypertension and preeclampsia. Methods: We conducted a cross-sectional study of 248 mother–infant dyads delivering at Tzaneio General Hospital of Piraeus, Greece. Eligible participants were of Greek origin or long-term residents (>10 years). Maternal venous and umbilical cord blood were obtained at birth and analyzed for serum 25(OH)D. Postpartum questionnaires captured sun exposure, supplement use, and selected lifestyle factors; clinical and obstetric data, including diagnoses of gestational hypertension and preeclampsia, were abstracted from medical records. We classified 25(OH)D as deficient (<20 ng/mL), insufficient (20–29 ng/mL), and, for risk-stratified analyses, treated values < 30 ng/mL as low. Results: Maternal 25(OH)D concentrations varied seasonally (winter 16.96 ± 9.60 ng/mL; summer 24.22 ± 12.57 ng/mL) and correlated with cord concentrations (r = 0.80). Most mothers (75–89%) had <30 ng/mL across seasons, and 73% of neonates were <20 ng/mL despite supplementation. Gestational hypertension occurred in 29/248 (11.7%) and preeclampsia in 15/248 (6.0%), with low maternal 25(OH)D common among affected women. Conclusions: In this cross-sectional study of an urban Mediterranean population, hypovitaminosis D was highly prevalent among mothers and neonates, with seasonal variation and clustering among hypertensive pregnancies. These findings support prenatal care strategies beyond fixed supplementation, incorporating season- and environment-sensitive dosing with screening and dietary counseling. Prospective studies are needed to clarify causality and refine supplementation targets. Full article
(This article belongs to the Special Issue Maternal-Fetal and Neonatal Medicine)
10 pages, 432 KB  
Article
Association Between Serum 25(OH)-Vitamin D and Heart Involvement in a Single-Centre Cohort of Children with Acute Rheumatic Fever During the Years 2004–2024
by Donato Rigante, Gabriella De Rosa, Angelica Bibiana Delogu, Giulia Pignataro, Claudia Di Pangrazio and Marcello Candelli
Biomedicines 2025, 13(10), 2502; https://doi.org/10.3390/biomedicines13102502 - 14 Oct 2025
Viewed by 788
Abstract
Background: An aberrant immune response against Streptococcus pyogenes combined with yet-unraveled genetic inference can induce acute rheumatic fever (ARF), but factors determining the specific development of rheumatic heart disease (RHD) are obscure. Objectives: To retrospectively assess general and laboratory data at [...] Read more.
Background: An aberrant immune response against Streptococcus pyogenes combined with yet-unraveled genetic inference can induce acute rheumatic fever (ARF), but factors determining the specific development of rheumatic heart disease (RHD) are obscure. Objectives: To retrospectively assess general and laboratory data at the onset of ARF in a single-centre cohort of children managed between 2004 and 2024, and to evaluate any potential relationship between serum vitamin D and the occurrence of RHD. Patients and Methods: Children with ARF diagnosed according to the revised Jones criteria, hospitalized and managed at the Department of Life Sciences and Public Health in our University, were considered; out of 90 eligible patients with post-streptococcal illness, 11 were not considered because they were diagnosed with post-streptococcal arthritis, while 1 was excluded due to incomplete inpatient data. A total final number of 78 consecutive children with ARF (39 males and 39 females) with a mean age of 10.6 ± 2.7 years was assessed via retrospective evaluation of medical records. Their demographic, clinical, and laboratory variables at disease onset, including C-reactive protein, anti-streptolysin-O titer, and 25-hydroxyvitamin D [25(OH)-vitamin D], were analyzed. Results: Sixty-six children (84.6% of the whole cohort) were found to have echocardiographic evidence of RHD. By dividing patients based on the presence of carditis, at the univariate analysis, we observed serum 25(OH)-vitamin D levels significantly lower in patients with cardiac involvement compared to those without (18 ± 6 versus 38 ± 8 ng/mL, p < 0.001). In addition, the proportion of patients with normal serum vitamin D levels was significantly higher among those without cardiac involvement (92%, p < 0.001). To account for any potential confounding factors, we performed a multivariate analysis using logistic regression, adjusted for sex and age, finding that 25(OH)-vitamin D levels lower than 30 ng/mL were the only variable associated with RHD (OR 27.752; 95% CI: 2.885–266.996). No relationship between vitamin D and the month of the year at diagnosis of ARF and RHD was found. Conclusions: Hypovitaminosis D was identified as a factor potentially associated with RHD occurrence in a single-centre cohort of children with ARF evaluated over two decades. This result may suggest that vitamin D deficiency contributes to the occurrence of carditis in ARF. Full article
(This article belongs to the Section Molecular and Translational Medicine)
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17 pages, 626 KB  
Article
Seasonal and Environmental Determinants of Maternal and Neonatal Vitamin D Status: A Cross-Sectional Observational Cohort Study in Urban Greece
by Artemisia Kokkinari, Maria Dagla, Kleanthi Gourounti, Antigoni Sarantaki, Giannoula Kirkou, Maria Iliadou, Evangelia Antoniou and Georgios Iatrakis
Healthcare 2025, 13(20), 2568; https://doi.org/10.3390/healthcare13202568 - 13 Oct 2025
Cited by 2 | Viewed by 1121
Abstract
Background: Cutaneous synthesis of vitamin D depends primarily on exposure to solar ultraviolet B (UVB) radiation. Nevertheless, populations in the Mediterranean region, including pregnant women, continue to experience high rates of hypovitaminosis D. Pregnancy is a particularly vulnerable period due to increased physiological [...] Read more.
Background: Cutaneous synthesis of vitamin D depends primarily on exposure to solar ultraviolet B (UVB) radiation. Nevertheless, populations in the Mediterranean region, including pregnant women, continue to experience high rates of hypovitaminosis D. Pregnancy is a particularly vulnerable period due to increased physiological demands and reduced outdoor activity. The aim of this study was to examine the seasonal and environmental determinants of maternal and neonatal vitamin D status in an urban Greek population. Methods: We conducted a cross-sectional observational study on 248 pregnant women and their neonates admitted for delivery at Tzaneio General Hospital of Piraeus between September 2019 and January 2022. Serum 25-hydroxyvitamin D [25(OH)D] concentrations were measured and temporally matched with environmental variables including UV index, sunshine hours, ambient temperature, and PM2.5 levels. Results: Both maternal and neonatal 25(OH)D levels exhibited marked seasonal variation, with levels peaking in late summer and declining sharply in winter. A significant positive correlation was observed between UV index and vitamin D concentrations (r = 0.45, p < 0.001), while elevated PM2.5 concentrations were inversely associated with vitamin D status. Despite supplementation, insufficiency persisted in most neonates, particularly during the low-UV season. This underlines the need for comprehensive prenatal care strategies, integrating both supplementation policies and individualized nutritional counseling, to better secure maternal and neonatal vitamin D adequacy. Conclusions: Seasonal and environmental factors, particularly solar radiation and particulate air pollution, have a decisive role in determining maternal and neonatal vitamin D status, even in regions with abundant sunlight. These findings emphasize the importance of adaptive prenatal care strategies that combine supplementation with dietary counseling and take into account seasonal variation and air quality. In addition, the study provides novelty by integrating maternal–neonatal vitamin D status with environmental exposure metrics such as UV and PM2.5. Full article
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27 pages, 358 KB  
Review
Vitamin D as an Immune Modulator in Systemic Lupus Erythematosus: A Narrative Review
by Oana Raluca Predescu, Florentin Ananu Vreju, Stefan Cristian Dinescu, Cristina Elena Bita, Anca Emanuela Musetescu, Alesandra Florescu and Paulina Lucia Ciurea
Life 2025, 15(10), 1580; https://doi.org/10.3390/life15101580 - 10 Oct 2025
Cited by 1 | Viewed by 2938
Abstract
Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease in which environmental factors modulate genetically determined immune dysregulation. Vitamin D has emerged as a plausible modifier of disease expression because its active metabolite signals through the vitamin D receptor on innate and adaptive [...] Read more.
Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease in which environmental factors modulate genetically determined immune dysregulation. Vitamin D has emerged as a plausible modifier of disease expression because its active metabolite signals through the vitamin D receptor on innate and adaptive immune cells and influences antigen presentation, cytokine balance, and lymphocyte differentiation. This narrative review synthesizes current evidence on vitamin D status and supplementation in SLE with attention to organ-specific domains. Observational studies consistently report high rates of hypovitaminosis D in SLE and associations with less favorable clinical profiles, including higher global and renal disease activity, adverse cardiometabolic features, greater infection vulnerability, and neuropsychiatric manifestations. Preclinical models demonstrate neuroprotective and barrier-stabilizing actions of vitamin D analogs, supporting biological plausibility. Interventional trials indicate that supplementation safely corrects deficiency and shows signals of benefit for selected outcomes (e.g., modest activity reductions or fatigue in specific contexts), although effects on interferon signatures, complement, and autoantibodies are heterogeneous and often limited. Overall, current evidence supports optimization of vitamin D status as a low-risk adjunct in comprehensive SLE care while highlighting the need for adequately powered, organ-focused randomized trials using standardized measurements and prespecified endpoints to define causality, therapeutic targets, and long-term safety. Full article
(This article belongs to the Section Medical Research)
11 pages, 234 KB  
Article
Vitamin D Receptor Gene Variants Associated with Serum 25(OH)D3 Levels in Patients with Dry Eye Syndrome
by Borivoje Savic, Svetlana Stanojlovic, Bozidar Savic, Jelena Kostic, Margita Lucic, Katarina Jankovic Terzic and Bojana Dacic-Krnjaja
Life 2025, 15(10), 1552; https://doi.org/10.3390/life15101552 - 3 Oct 2025
Viewed by 1529
Abstract
Introduction: Dry Eye Syndrome (DES) is a multifactorial disorder of the ocular surface, characterized by complex interactions between environmental factors, immune dysregulation, and potential genetic predispositions. Vitamin D deficiency, known for its immunomodulatory properties, has increasingly been implicated in the pathogenesis of DES; [...] Read more.
Introduction: Dry Eye Syndrome (DES) is a multifactorial disorder of the ocular surface, characterized by complex interactions between environmental factors, immune dysregulation, and potential genetic predispositions. Vitamin D deficiency, known for its immunomodulatory properties, has increasingly been implicated in the pathogenesis of DES; however, the underlying mechanisms remain insufficiently elucidated. Of particular interest is the vitamin D receptor (VDR) gene, whose polymorphisms may influence the bioavailability and biological activity of vitamin D. Objective: The aim of this study was to investigate the association between serum 25-hydroxyvitamin D [25(OH)D3] levels and selected polymorphisms in the VDR gene (Taq, Fok, Apa, and Bsm) in patients with DES and to analyze their potential clinical and genetic interactions. Methods: This prospective observational study included 60 patients with a confirmed diagnosis of DES. Serum 25(OH)D3 levels were measured, and genotyping of four VDR single-nucleotide polymorphisms (SNPs) was performed using PCR followed by restriction fragment length polymorphism analysis. Genotype distributions were assessed in relation to vitamin D status using appropriate statistical tests and Hardy–Weinberg equilibrium analysis. Results: Over 85% of patients exhibited insufficient or deficient vitamin D levels. Among the analyzed SNPs, only the ApaI polymorphism (rs7975232) showed a statistically significant association with vitamin D status (p = 0.0384), with the homozygous AA genotype being more prevalent among patients with hypovitaminosis. The remaining polymorphisms (TaqI, FokI, BsmI) did not reach statistical significance; however, potential trends were observed that may warrant further investigation in larger cohorts. Conclusion: The findings suggest a potential role for VDR gene variability in the regulation of systemic vitamin D levels in patients with DES. Identification of specific genotypes may contribute to the development of personalized diagnostic and therapeutic strategies, particularly for patients with treatment-resistant forms of the disease. These results support the integration of genetic biomarkers and nutritional parameters into modern ophthalmologic practice. Full article
(This article belongs to the Special Issue Cornea and Anterior Eye Diseases: 2nd Edition)
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