25OHD Levels Research Articles

The correlation of obesity status with serum 25-hydroxyvitamin D in US Asian adults: NHANES 2011-2018.

There is a correlation between obesity and 25-hydroxyvitamin D (25OHD) that tends to be negative. However, this relationship varies among different races. In this study, Asian adults with and without obesity were compared in terms of their levels of 25OHD. We carried out a cross-sectional analysis on 2664 non-Hispanic Asian adults who participated in the National Health and Nutrition Examination Survey (NHANES) conducted between 2011 and 2018. To examine the connection between obese status, body mass index (BMI), waist circumference (WC) and weight, and 25OHD, we ran multivariate linear regression models and multivariate logistic regression models. After adjusting for all confounding factors, obesity status shows a significant positive correlation with vitamin D deficiency (model 3: OR = 2.318, 95% CI:1.317, 4.082). This positive correlation remains significant in males (males: OR = 2.713, 95% CI: -13.398, 5.217). In all three models, a negative association was observed between obesity status and 25OHD (model 1: β = -4.535, 95% CI: -6.987, -2.083; model 2 β = -4.249, 95% CI: -6.549, -2.039; model 3 β = -1.734, 95% CI: -7.285, 3.816). After controlling for covariates, there was a significant negative correlation between WC and 25OHD when stratified by gender and obesity status in both males with and without obesity (males with obesity: β = -1.461, 95% CI: -2.485, -0.436; males without obesity: β = -0.855. 95% CI: -1.499, -0.210). In males with obesity, there was a very strong positive connection between body weight and 25OHD (β = 0.912, 95% CI: 0.227, 1.597). In addition, neither gender's obese individuals showed a significant link between BMI and 25OHD. This study demonstrated a positive correlation between obesity and vitamin D deficiency and a negative correlation between obesity and 25OHD in Asian American adults. Additionally, among male obese individuals, there was a significant negative correlation between WC and 25OHD, an observation that needs to be validated in further prospective studies.

Investigating vitamin D status following severe acute respiratory syndrome coronavirus 2 infection and its relationship with long coronavirus disease

Abstract Objective Health-care systems are facing a brand new difficulty as a result of post-COVID-19 syndrome. The relationship between long COVID and vitamin d.(25OHD levels was not extensively studied. Also, to our knowledge, no study evaluated vit d.(25OHD) levels and their relation to long COVID in the long-term period [3–6 months) after COVID infection. This study aims to evaluate vit d.(25OHD) levels post-COVID-19 infection and its relation to persistent symptoms in long-term COVID. Patients and methods A cross-sectional, single-center study involving 84 patients who were recruited during the period from December 2021 to May 2022, during the previous 6 months after the COVID-19 sickness. Complete history, clinical examination, and laboratory analysis [C-reactive protein, D-dimer, total leukocyte count, lymphocyte count. Serum vit d.(25OHD), and HRCT chest were performed. Results Of the patients, 44% had insufficient levels [20–30 ng/dL), 36% had deficient vitamin D levels [<20 ng/dL), and only 19% reported normal levels. In the examined groups, there was no association between vitamin d.(25OHD) levels and post-COVID-19 symptoms. Conclusion The study population had a high rate of vit d.(25OHD) insufficiency; however, no association was found between vit d.(25OHD) level and post-COVID-19 symptoms. The relation between long COVID-19 pathophysiology and the immune system is more complicated. More research is required to determine whether vit d.(25OHD) may have a part in long-term COVID-19.

25-hydroxyvitamin D and Endometriosis: A bidirectional Mendelian randomization study.

Numerous studies have demonstrated a correlation between serum 25-hydroxyvitamin D (25OHD) and endometriosis. However, the precise nature of this association remains elusive. The causal connection between 25OHD and endometriosis remains uncertain, as it is yet to be determined whether one directly influences the other. The objective of our research was to investigate the cause-and-effect connection between 25OHD and endometriosis. The study employed Mendelian randomization (MR) in a bidirectional two-sample investigation to examine the causal relationship between 25OHD and endometriosis. The analysis utilized the most recent publicly accessible statistics from the genome-wide association study (GWAS) encompassing 25OHD, endometriosis, and its five subtypes. The primary analytical approach employed was Inverse-Variance Weighting (IVW), accompanied by supplementary analysis methods including weighted median, MR-Egger, simple mode, and weighted mode. Furthermore, sensitivity analyses were conducted to assess the potential influence of heterogeneity and pleiotropy on the MR outcomes. MR primary analysis showed no significant causal effect of 25OHD on endometriosis (OR = 0.892, 95%CI = 0.745 ~ 1.068, P = 0.213). Similarly, there was no evidence to support a causal relationship of endometriosis on 25OHD (IVW Beta = 0.005, 95%CI = 0.993 ~ 1.018, P = 0.406). However, when conducting MR analysis on different subtypes of endometriosis and 25OHD, we found a positive correlation between endometriosis of ovary and 25OHD level (IVW Beta = 0.012, 95%CI = 1.002 ~ 1.022, P = 0.024). This study indicates that there is no causal relationship between serum 25OHD and endometriosis. However, it is important to note that serum 25OHD levels will increase in patients with endometriosis of the ovary. Further observational studies and clinical trials are indispensable.

The protective role of oily fish intake against type 2 diabetes: insights from a genetic correlation and Mendelian randomization study.

Previous research has underscored the association between oily fish intake and type 2 diabetes (T2DM), yet the causality remains elusive. A bidirectional univariable Mendelian Randomization (MR) analysis was employed to evaluate the causal effects of oily fish and non-oily fish intake on T2DM. Replication analysis and meta-analysis were conducted to ensure robust results. Multivariable MR analysis was utilized to assess confounders, and further mediation MR analysis discerned mediating effects. Linkage Disequilibrium Score (LDSC) analysis was undertaken to compute genetic correlations. Inverse variance weighted (IVW) was the primary method, complemented by a series of sensitivity analyses. The LDSC analysis unveiled a significant genetic correlation between oily fish intake and T2DM (Genetic correlation: -0.102, p = 4.43 × 10-4). For each standard deviation (SD) increase in genetically predicted oily fish intake, the risk of T2DM was reduced by 38.6% (OR = 0.614, 95% CI 0.504 ~ 0.748, p = 1.24 × 10-6, False Discovery Rate (FDR) = 3.72 × 10-6). The meta-analysis across three data sources highlighted a persistent causal association (OR = 0.728, 95% CI 0.593 ~ 0.895, p = 0.003). No other causal effects were identified (all p > 0.5, FDR > 0.5). The main outcomes remained consistent in most sensitivity analyses. Both MVMR and mediation MR analyses emphasized the mediating roles of triglycerides (TG), body mass index (BMI), and 25-hydroxyvitamin D (25OHD) levels. To encapsulate, there's an inverse association between oily fish intake and T2DM risk, suggesting potential benefits of oily fish intake in T2DM prevention.

Circulating 25-hydroxyvitamin D and survival outcomes of colorectal cancer: evidence from population-based prospective cohorts and Mendelian randomisation

BackgroundTo investigate the association between circulating 25-hydroxyvitamin D (25-OHD) and colorectal cancer (CRC) survival outcomes.MethodsWe conducted analyses among the Study of Colorectal Cancer in Scotland (SOCCS) and the UK Biobank (UKBB). Both cancer-specific survival (CSS) and overall survival (OS) outcomes were examined. The 25-OHD levels were categorised into three groups, and multi-variable Cox-proportional hazard models were applied to estimate hazard ratios (HRs). We performed individual-level Mendelian randomisation (MR) through the generated polygenic risk scores (PRS) of 25-OHD and summary-level MR using the inverse-variance weighted (IVW) method.ResultsWe observed significantly poorer CSS (HR = 0.65,95%CI = 0.55–0.76,P = 1.03 × 10−7) and OS (HR = 0.66,95%CI = 0.58–0.75,P = 8.15 × 10−11) in patients with the lowest compared to those with the highest 25-OHD after adjusting for covariates. These associations remained across patients with varied tumour sites and stages. However, we found no significant association between 25-OHD PRS and either CSS (HR = 0.98,95%CI = 0.80–1.19,P = 0.83) or OS (HR = 1.07,95%CI = 0.91–1.25,P = 0.42). Furthermore, we found no evidence for causal effects by conducting summary-level MR analysis for either CSS (IVW:HR = 1.04,95%CI = 0.85–1.28,P = 0.70) or OS (IVW:HR = 1.10,95%CI = 0.93–1.31,P = 0.25).ConclusionThis study supports the observed association between lower circulating 25-OHD and poorer survival outcomes for CRC patients. Whilst the genotype-specific association between better outcomes and higher 25-OHD is intriguing, we found no support for causality using MR approaches.

Understanding the Impact of COVID-19 on Roma Vulnerable Communities in Western Romania: Insights and Predictive Factors from a Retrospective Study.

The COVID-19 pandemic disproportionately affected vulnerable populations like Roma patients in Western Romania due to marginalization and limited healthcare access. A retrospective study analyzed COVID-19 cases between March 2020 and August 2022 using data from the Directorate of Public Health in Timis county. Demographic, epidemiological, clinical, and laboratory data were assessed, along with risk factors and biomarkers for ICU admission and mortality prediction. The following biomarkers were assessed: C-reactive protein (CRP), ferritin (FER), IL-6, D-dimers, lactate dehydrogenase (LDH), high density lipoprotein cholesterol (HDL), and 25-OH vitamin D (25-OHD). In comparison with the general population (GP), Roma patients were more overweight (p = 0.0292), came from rural areas (p = 0.0001), could not recall transmission source (p = 0.0215), were admitted to the intensive care unit (ICU, p = 0.0399) more frequently, had worse symptomatology (p = 0.0490), showed more elevated levels of CRP (p = 0.0245) and IL-6 (p < 0.0001) and lower levels of HDL (p = 0.0008) and 25-OHD (p = 0.0299). A stronger, significant correlation was observed between CRP and severity (rho = 0.791 vs. 0.433 in GP), and an inverse stronger significant one was observed between HDL and severity (rho = -0.850 vs. -0.734 in GP) in the Roma patients. The male sex continues to be an important risk factor for ICU admission (OR = 2.379) and death (OR = 1.975), while heavy smoking was more important in relation to ICU admission (OR = 1.768). Although the Roma ethnicity was 1.454 times more at risk of ICU admission than the GP, this did not prove statistically significant (p = 0.0751). CRP was the most important predictive factor in regards to admission to the ICU for both Roma (OR = 1.381) and the GP (OR = 1.110) and in regards to death (OR = 1.154 for Roma, OR = 1.104 for GP). A protective effect of normal values of HDL and 25-OHD was observed in the GP for both ICU admission (OR = 0.947, 0.853, respectively) and death (OR = 0.920, 0.921, respectively), while for the Roma group, normal 25-OHD values were only considered protective in regards to death (OR = 0.703). Cutoff values for ICU admission were 28.98 mg/L for Roma and 29.03 mg/L for GP patients, with high specificity for both groups (over 95). Higher rates of ICU admissions, severe symptomatology, and distinct laboratory biomarker profiles among Roma patients emphasize the critical importance of personalized care strategies and targeted interventions to mitigate the disproportionate burden of COVID-19 on vulnerable communities. CRP values at admission have had a clear impact as a risk assessment biomarker for Roma patients, while the significance of IL-6, HDL, and 25-OHD should also not be overlooked in these patients.

A Fracture Liaison Service to Address Vitamin D Deficiency for Patients Hospitalized for Osteoporotic Fracture.

Addressing vitamin D deficiency (VDD) is important for fracture secondary prevention. To explore the function of a fracture liaison service (FLS) to address VDD. An observational study of patients admitted to the Massachusetts General Hospital with fractures between January 1, 2016, and October 31, 2023, cared for by the FLS. Ergocalciferol 50 000 international units (50ku-D2) oral daily for 3 to 7 days. VDD prevalence. Efficacy of inpatient daily 50ku-D2 in raising serum 25-hydroxyvitamin D (25OHD) levels. Of the 2951 consecutive patients, 724 (24.53%) had VDD (defined by 25OHD ≤ 19 ng/mL). Men (252/897, or 28.09%) were more likely than women (472/2054, or 22.98%) to have VDD (P = .003). VDD was seen in 41.79% (117/280), 24.41% (332/1360), and 20.98% (275/1311) of patients of aged ≤59, 60 to 79, and ≥80 years, respectively (P < .00001). Of the 1303 patients with hip fractures, 327 (25.09%) had VDD, which was associated with a longer length of stay (8.37 ± 7.35 vs 7.23 ± 4.78 days, P = .009) and higher trend of 30-day-readmission rate (13.63% vs 18.35%, P = .037). In a cohort of 32 patients with complete data, each dose of 50ku-D2 increased serum 25OHD by 3.62 ± 2.35 ng/mL without affecting serum calcium or creatinine levels. VDD was seen in nearly 25% of Massachusetts General Hospital FLS patients and more prevalent in male and younger patients. VDD was associated with longer length of stay and higher 30-day-readmission risk in patients with hip fracture. Daily 50ku-D2 appeared to be a practical way to quickly replete vitamin D in the inpatient setting.

Effect of the Season on Blood Changes of Oxidative Stress Index in the Italian Mediterranean Buffalo (Bubalis bubalis).

Studies in cattle have shown that high temperatures increase the production of reactive oxygen species (ROS) causing an imbalance between ROS and the ability of antioxidant systems to detoxify and remove the reactive intermediates. As such studies remain limited in buffalo, the effect of temperature on oxidative stress was investigated through the oxidative stress index (OSi). Blood samples were collected from 40 buffaloes over 12 time points distributed over two years (2021, 2022). Samples were taken monthly during the hot and cold seasons. Plasma free oxygen radicals were determined using the d-ROMs test (Diacron, Italy), modified for a microplate procedure, and the results were expressed in arbitrary Carratelli Units (U.CARR). Plasma antioxidants were determined by using the BAP test (Diacron) in a dedicated spectrophotometer (Carpe Diem Free, Diacron). The OSi parameter was calculated as d-ROMs/BAP × 100. Temperature and humidity were recorded daily during the trial to calculate the Temperature Humidity Index (THI). For statistical analysis, year and season and their interactions were included in the model. The results of this study showed for the first time the effect of season on the oxidative stress in buffalo. The minimum and maximum THI values for the hot and cold season recorded during the experimental period were 79.27 ± 2.20 and 63.42 ± 3.20, respectively. Levels of d-ROMs and BAP were affected by the seasons (133.0 vs. 145.1 U.CARR, p = 0.0189, and 2489.19 vs. 2392.43 mml/L, p = 0.033, in the hot and cold season, respectively). A significant year × season interaction was found both for d-ROMs and BAP (p = 0.06 and p < 0.0001, respectively). Moreover, OSi was affected by season, showing a growing trend from hot to cold season (5.35 vs. 6.17, p < 0.0001), but, interestingly, it was unaffected by annual variation. Therefore, Osi could be considered a better and independent marker of oxidative status in buffalo, with respect to the evaluation of single determinations of d-ROMs and BAP. Lastly, there were no differences in the plasma 25OHD levels between seasons; concentrations were 12.24 and 10.26 ng/mL in the hot and cold season, respectively.

Wild Alaskan salmon supplementation increases 25-OHD levels in sled dogs

Vitamin D deficiency affects canines and humans alike. Athletes are a particularly high-risk group. Further research regarding optimal intake and supplementation is needed to establish the parameters of vitamin D status in both humans and canines and to create a physiologically-relevant definition for vitamin D sufficiency. The objectives of this study were to (1) compare 25-OHD (25-hydroxy vitamin D) levels in sled dogs before and after receiving a diet supplemented with wild Alaskan salmon and (2) correlate biomarkers associated with vitamin D metabolism to 25-OHD levels in sled dogs. Plasma samples from 14 working sled dogs between 10 months and 7 years of age were collected before and after a 4-week supplementation with »0.45 kg of salmon/day. Samples were analyzed using enzyme-linked immunosorbent assays (ELISA) for parathyroid hormone and vitamin D binding protein (DBP); 25-OHD levels were measured via radioimmunoassay. 25-OHD and DBP in sled dogs significantly increased after a 4-week supplementation with salmon (P=0.0011 and 0.0367, respectively). Additional variations in 25-OHD were observed when separated by sex (P=0.0404) and age (P&lt;0.0001). 57% of the dogs were deficient prior to the salmon supplementation and 14% at the completion of the study. Wild Alaskan salmon is one of the few food sources that provide appreciable amounts of vitamin D. A 4-week salmon supplementation in sled dogs was sufficient to improve 25-OHD concentrations in most sled dogs in this study. Confounding factors such as age and sex affect circulating 25-OHD levels.

Genetic variants and non-genetic factors associated with a high prevalence of vitamin D deficiency in full-term neonates in Malaysia

A high prevalence of vitamin D deficiency has been reported in Malaysian pregnant women, indicating that neonates at birth are at increased risk of vitamin D deficiency. Factors including low dietary vitamin D intake and single nucleotide polymorphisms in the vitamin D metabolism genes have been associated with this deficiency in the population. However, there was limited data available regarding the prevalence of neonatal vitamin D deficiency and the factors associated with it among neonates in Malaysia. Therefore, this study aimed to determine the prevalence of vitamin D deficiency and explore the associations between maternal and neonatal gene polymorphisms, as well as non-genetic factors and neonatal vitamin D deficiency. A total of 217 mother-neonate dyads were recruited for this study. Data on skin type, maternal sun exposure, dietary intake, as well as maternal and neonatal 25-hydroxyvitamin D (25OHD) concentrations were collected. Maternal and neonatal vitamin D Receptor (VDR) SNP (rs2228570) and Group-specific component (GC) SNPs (rs4588 and rs7041) genotypes were determined using high-resolution melting (HRM) and restriction fragment length polymorphism, respectively. The results showed that 60.4%, 71.4% and 95.4% of neonates had cord blood 25OHD levels below 25 nmol/L, 30 nmol/L and 50 nmol/L, respectively. After adjusting for the maternal vitamin D status, the maternal VDR rs2228570 GG genotype was significantly associated with neonatal vitamin D deficiency (25OHD<30 nmol/L) (aOR = 2.63, 95% CI: 1.18–5.87, p = 0.018). Maternal vitamin D supplement intake was found to be a protective factor. However, maternal and neonatal vitamin D binding protein (VDBP) SNPs were not associated with neonatal vitamin D deficiency. The high prevalence of neonatal vitamin D deficiency reported in this study indicates the urgent need for the development and implementation of strategies to improve neonatal vitamin D status. The findings suggest that maternal supplementation may be an effective approach to enhance the vitamin D status of neonates.

Demographic and disease-related factors impact bone turnover and vitamin D in children with hemato-oncological diseases.

Children with hemato-oncological diseases may have significant skeletal morbidity, not only during and after treatment but also at the time of diagnosis before cancer treatment. This study was designed to evaluate the vitamin D status and circulating bone metabolic markers and their determinants in children at the time of diagnostic evaluation for hemato-oncological disease. This cross-sectional study included 165 children (91 males, median age 6.9yr range 0.2-17.7yr). Of them, 76 patients were diagnosed with extracranial or intracranial solid tumors, 83 with leukemia, and 6 with bone marrow failure. Bone metabolism was assessed by measuring serum 25OHD, PTH, bone alkaline phosphatase, intact N-terminal propeptide of type I procollagen, and C-terminal cross-linked telopeptide of type I collagen. Vitamin D deficiency was found in 30.9% of children. Lower 25OHD levels were associated with older age, lack of vitamin D supplementation, season outside summer, and a country of parental origin located between latitudes -45° and 45°. Children diagnosed with leukemia had lower levels of markers of bone formation and bone resorption than those who had solid tumors or bone marrow failure. In conclusion, vitamin D deficiency was observed in one-third of children with newly diagnosed cancer. Bone turnover markers were decreased in children with leukemia, possibly because of the suppression of osteoblasts and osteoclasts by leukemic cells. The identification of patients with suboptimal vitamin D status and compromised bone remodeling at cancer diagnosis may aid in the development of supportive treatment to reduce the adverse effects of cancer and its treatment.

Human milk-derived versus bovine milk-derived fortifier use in very low birth weight infants: growth and vitamin D status.

Human milk-derived fortifier (HMDF) coupled with human milk feeding in extremely premature infants reduces the adverse outcome risks of early exposure to bovine milk ingredients but may not provide enough nutrients for adequate catch-up growth compared with bovine milk-derived fortifier (BMDF). This study aims to compare HMDF and BMDF effects on growth parameters and serum 25-hydroxy vitamin D (25OHD) levels in preterm very low birth weight (VLBW) infants during the first 8 weeks of life. We present a retrospective chart review of inpatient VLBW infants with birth weight <1,500 g and gestational age <32 completed weeks who received either their mother's milk or donor breast human milk fortified with HMDF or BMDF for the first 8 weeks. Weight, head circumference, length gain, and 25OHD level were calculated at 4 and 8 weeks of age. A total of 139 VLBW infants (91 HMDF + 48 BMDF) received fortified human milk without any supplemental premature formula from birth to 4 weeks of age, of whom 44 (37 HMDF + 7 BMDF) continued until 8 weeks of age. There was no statistically significant difference in the growth parameters between the two groups at 4 and 8 weeks of age. Serum 25OHD level in the HMDF group was significantly higher compared with that in the BMDF group at 4 weeks of age despite receiving lower vitamin D supplementation. Similar gain in growth parameters in HMDF and BMDF groups at 4 and 8 weeks of age was observed, suggesting that HMDF provides adequate nutrients for growth in VLBW infants. A higher 25OHD level in HMDF may suggest better absorption.

Clinical and genetic determinants of vitamin D receptor expression in cutaneous melanoma patients.

Decrease of vitamin D receptor (VDR) expression is observed in melanocytic naevi and melanoma compared to normal skin. Little is known about factors influencing VDR expression in cutaneous melanoma (CM). We investigated the correlation of VDR expression in CM with 25-hydroxy vitamin D (25OHD) levels, demographic/clinical parameters, genetic variants of VDR and pathology of the primary tumor. Demographic/clinical parameters were recorded in 407 prospectively recruited CM patients of a multi-center controlled study (ViDMe trial). We determined VDR expression both in the nucleus and in the cytoplasm by semi-quantitative assessment in CM tissue using histochemistry in 279 patients, expressed in percentages and histoscore (H-score). Genomic DNA from 332 patients was extracted to genotype thirteen VDR single nucleotide polymorphisms (SNPs) using TaqMan. VDR expression in CM tissue from 279 patients was correlated with clinical/demographic parameters and 25OHD levels (univariable and multivariable analysis), VDR SNPs (univariable analysis) and pathology parameters of primary CM tissue (univariable analysis). Cytoplasmic VDR expression was increased in patients who stated to have a high sun exposure during their life compared to patients with low sun exposure (p H-score,univariable : 0.001, p H-score,multivariable : 0.004). The A allele of the genetic VDR polymorphism Fok1 was associated with a higher expression of the VDR in the cytoplasm (p cytoplasmic, univariable : 0.001 and p H-score, univariable : 0.02). In the primary tumor, presence of mitosis (p nucleus,%, univariable : 0.002) and perineural invasion (p nucleus,%,univariable : 0.03) were significantly associated with low nuclear VDR expression. ClinicalTrials.gov Identifier: NCT01748448.

Histomorphometric analysis of patients with femoral neck fracture and 25-hydroxyvitamin D deficiency: a cross-sectional study.

Vitamin D deficiency causes osteoporosis, bone mineralization disorders, and osteomalacia. Osteomalacia is diagnosed using blood biochemical tests, clinical symptoms, and imaging; however, accurate detection of mineralization disorders requires tissue observation. We investigated the prevalence of bone mineralization disorders and their relationship with serum 25-hydroxyvitamin D (25OHD) levels in patients with untreated osteoporosis with femoral neck fractures. A non-demineralized specimen was prepared from the femoral head removed during surgery in 65 patients. Bone histomorphometry of cancerous bone in the femoral head center was conducted. Osteoid volume per bone volume (OV/BV) and osteoid thickness (O.Th) were measured as indicators of mineralization disorder. The mean serum 25OHD level (11.9 ± 5.7ng/mL) was in the deficiency range (< 12ng/mL). There were no clinically diagnosed cases of osteomalacia (OV/BV > 10% and O.Th > 12.5µm); however, one case of mineralization disorder, considered histologically pre-osteomalacia (OV/BV > 5% and O.Th < 12.5µm), was observed (OB/BV, 17.6%; O.Th, 12.3µm). Excluding this case, those with severe (25OHD < 12ng/mL, at risk of osteomalacia; n = 39) and non-severe deficiency (25OHD ≥ 12ng/mL; n = 25) did not significantly differ in OV/BV (%; 0.77 ± 0.54 vs. 0.69 ± 0.38, p = 0.484) or O.Th (µm; 5.32 ± 1.04 vs. 5.13 ± 0.78, p = 0.410). Further, 25OHD and OV/BV were not significantly correlated (R = -0.124, p = 0.327). This is the first study in the twenty-first century to examine serum 25OHD concentrations and bone mineralization disorders in Japanese patients with osteoporosis. The results indicate that vitamin D deficiency does not necessarily cause bone mineralization disorders and rarely leads to osteomalacia.

Influence of hydroxyurea on tubular phosphate handling in sickle cell nephropathy

ObjectiveThis study aims to evaluate the markers of tubular phosphate handling in adults with sickle cell anemia (SCA) and the influence of hydroxyurea (HU), the degree of anemia and Hb F concentration on these markers. MethodsEighty-eight steady state SCA patients in outpatient follow-up in Fortaleza, Ceara, Brazil and 31 healthy individuals were included in this study. Vitamin D (25OHD) was measured by enzyme-bound fluorescence assay, intact parathyroid hormone (iPTH) by electrochemiluminescence, and serum and urinary phosphate and creatinine by colorimetric methods. Details of Hb F and HU use were obtained from clinical records. Tubular reabsorption of phosphate (TRP) and maximum tubular reabsorption of phosphate (MTRP) were calculated. SCA patients were stratified according to the use of HU, degree of anemia and percentage of Hb F. The significance level was set for p-values <0.05. ResultsCompared to controls the 25OHD level (25 ± 11 vs. 30 ± 9 pg/mL) was lower in SCA, while serum phosphate and MTRP were higher (3.86 ± 0.94 vs. 3.46 ± 0.72 and 3.6 ± 1.21 vs. 3.21 ± 0.53, respectively). There was no significant difference in iPTH, TRP and phosphaturia. Serum phosphate showed correlation with TRP (r = 0.32; p-value = 0.008) and MTRP (r = 0.9; p-value <0.001) in SCA. Patients taking HU, especially those with Hb F >10 % presented reduced serum phosphate levels, and TRP and MTRP rates. Those with mild anemia presented reduced serum phosphate levels and MTRP rates. ConclusionSerum phosphate levels and renal phosphate reabsorption rate were increased in SCA. HU use, high Hb F concentration and total Hb were associated with better control of tubular phosphate handling markers.

Vitamin D status and supplementation, calcium supplementation, and timing of natural menopause

Vitamin D status has been inconsistently associated with ovarian reserve and menopause. We used data from the Sister Study cohort to examine the associations of vitamin D supplement use, total 25-hydroxyvitamin D (25OHD) level, and calcium supplement use with the timing of natural menopause. Vitamin D and calcium supplement use were assessed on a questionnaire at baseline (mean age: 46) and two follow-up time points, and characterized in multiple ways based on type, dose, and duration of use. Serum samples from a random subset of participants were analyzed for total 25OHD (25OHD3 + 25OHD2 + epi-25OHD3) using liquid chromatography-mass spectrometry. Menopause was assessed at each yearly follow-up with the question “Have you had a menstrual period in the past 12 months?”; if the response was “no”, age at last menstrual period was recorded. We censored women at time of hysterectomy or medically induced menopause, death, loss to follow-up or October 2020. We used multivariable Cox proportional hazard models with age as the time scale to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs), adjusting for race/ethnicity, education, body mass index, alcohol use, smoking status, and physical activity. Among the 13,102 eligible premenopausal participants, 8897 experienced natural menopause during follow-up. Concomitant use of a multivitamin and a vitamin D supplement was associated with slightly earlier menopause (HR(CI): 1.10 (0.98, 1.24)). None of the remaining vitamin D or calcium supplement variables (alone or in combination) were meaningfully associated with timing of natural menopause. In a subsample with 25OHD measurements (n = 906), neither total 25OHD nor 25OHD3 was associated with timing of menopause. Our study includes, on average, 6 years of follow-up from an average age of 46 years and did not find associations between vitamin D or calcium supplement use and timing of menopause. Future studies should focus on a life course approach to this question and include 25OHD measures from early mid-life when examining menopause timing.

Bone Health and Antiepileptic Drugs in Children with Epilepsy: A Pilot Study

Epilepsy, a chronic neurological disorder necessitating prolonged antiepileptic medication, has been associated with deficiencies in vitamin D and related bone disorders in children. This study aims to investigate the prevalence of vitamin D deficiency, calcium deficiency, and bone diseases in children undergoing antiepileptic drug (AED) therapy. A retrospective study was conducted on 60 children (0-16 years old) with epilepsy at King Fahad Specialist Hospital-Dammam from 2016 to 2018. Participants were administered 800 IU/day of vitamin D for 6 months. Comprehensive assessments, including tests for calcium, phosphorus, 25-hydroxyvitamin D (25-OHD), 1,25-hydroxyvitamin D (1,25 OHD), parathyroid hormone (PTH), thyroid function [thyroid-stimulating hormone (TSH)], alkaline phosphatase (ALP), and bone density, were performed after 6 months of oral vitamin D supplementation. No significant associations were observed between age, sex, age of onset, duration of epilepsy, symptoms of vitamin D deficiency, dietary factors, and the levels of calcium, phosphorus, 25-OHD, 1,25-OHD, PTH, TSH, ALP, and bone scan. Carbamazepine (CBZ) was the only AED that affected bone metabolism in general (P = 0.024). Calcium was mostly found to be abnormal after using AED with vitamin D (800 IU/day) for 6 months (P = 0.05). 25-OHD deficiency was associated with use of CBZ in pediatric epilepsy. Considering its potential impact on bone metabolism, higher vitamin D doses may be advisable for children on long-term AED therapy to mitigate these abnormalities.

Vitamin D Deficiency in Patients Hospitalized for Heart Failure Living in the Tropics.

Vitamin D, as a steroid hormone, has multiple effects on human body and its deficiency has been associated with an increased risk of heart failure (HF) and unfavorable outcomes. The present study investigated the prevalence of vitamin D deficiency (VDD) and its relationship with cardiometabolic parameters in patients hospitalized for HF living in the city of Recife (latitude 8° South). Analytical cross-sectional study, with men and women aged 40-64 years. The HF group was recruited during hospitalization due to decompensation. A matched control group was recruited from the general endocrine clinics. Vitamin D status was assessed by measuring serum 25-hydroxyvitamin D (25OHD), considering deficiency when 25OHD <20 ng/mL (<50 nmol/L). A total of 243 patients were evaluated (HF group: 161, control group: 82). Lower serum 25OHD levels were observed in the HF group (25.2±9.4 vs. 30.0±7.7ng/mL; p<0.001), as well as a higher prevalence of VDD (27.3% vs. 9.8%; prevalence ratio, 2.80; 95% confidence interval, 1.38-5.67; p=0.002). In patients with HF, VDD was associated with diabetes mellitus (65.9% vs. 41.0%; p=0.005) and female sex (65.9% vs. 44.4%; p=0.015). In the subgroup with VDD, higher values of hemoglobin A1c (7.9% [6.0-8.9] vs. 6.2% [5.7-7.9]; p=0.006) and dyslipidemia were also observed. We found higher rates of VDD in patients hospitalized for HF and this was associated with deleterious laboratory metabolic parameters.

The Effect of Vitamin D Supplementation in Pregnant Women with Overweight and Obesity: A Randomised Controlled Trial.

The impact of vitamin D supplementation on 25-hydroxyvitamin D (25OHD) levels, metabolic status, and pregnancy outcomes in pregnant women with overweight and obesity (OW/OB) is uncertain. This study aimed to examine whether administrating 800 IU of vitamin D3 orally would improve maternal serum 25OHD levels, lipid profile, and pregnancy outcomes compared to 400 IU. This was a two-arm, parallel, non-blinded randomised controlled trial involving 274 pregnant women recruited from KK Women's and Children's Hospital, with a body mass index of ≥25 kg/m2 within 16 weeks gestation. The participants were randomly assigned to receive 800 IU/day (intervention group) or 400 IU/day (control group) of oral vitamin D3 supplements. The primary outcomes were maternal serum 25OHD and lipid levels at 24-28 weeks gestation. The secondary outcomes included maternal and birth outcomes. Compared with controls (n = 119), the intervention group (n = 112) exhibited higher 25OHD levels at 24-28 weeks gestation (adjusted mean difference 6.52 nmol/L; 95% confidence interval 2.74, 10.31). More women in the intervention group achieved sufficient 25OHD levels (77.7% vs. 55.5%; p < 0.001). No differences were observed in lipid profiles or maternal or birth outcomes between the groups. An additional 400 IU of oral vitamin D3 supplementation increased serum 25OHD levels but did not impact lipid profiles or pregnancy outcomes.

Tip 1 Diyabette Serum Vitamin D Bağlayan Protein Düzeylerinin Araştırılması: Glisemik Kontrol ve Hastalık Süresinin Etkisi

Aim: Patients with type 1 diabetes mellitus (T1DM) are known to be more prone to vitamin D deficiency. Vitamin D studies in this&#x0D; patient population have traditionally been performed using serum 25OHD levels. However, vitamin D binding protein (VDBP) has&#x0D; been less studied. This study aims to compare serum VDBP levels in T1DM with healthy controls. It also aims to investigate the factors&#x0D; affecting VDBP levels such as disease duration, HbA1c, insulin dose, and age in diabetic subjects.&#x0D; Material and Methods: A research study was conducted at Çanakkale Onsekiz Mart University Health Practice and Research Hospital.&#x0D; The study included 11-17 years old children with T1DM and healthy controls. Serum VDBP and 25OHD concentrations were compared&#x0D; with appropriate statistical methods according to the normal distribution of relevant parameters. For the diabetic subjects, insulin doses&#x0D; and duration of diabetes were recorded. Spearman’s correlation test was utilized to assess associations between continuous variables, and&#x0D; regression analysis was employed to determine predictors of serum VDBP levels.&#x0D; Results: The study enrolled 89 subjects, including 40 with diabetes. Serum 25OHD levels were similar in the T1DM group and control&#x0D; group (17.03 IQR:12.89-22.08) and (17.62 IQR:11.68-24.48), respectively (p=0.701). However, VDBP levels were significantly lower in&#x0D; the T1DM group (335 μg/ml, IQR: 199.8-517.2 μg/ml) compared to the control group (471.2 μg/ml, IQR: 368.3-533.2 μg/ml) (p &lt; 0.015).&#x0D; In the entire group, only the presence of diabetes affected VDBP levels (B=87.236, SE=34.802, p=0.014). On the other hand, HbA1c,&#x0D; duration of diabetes, and insulin dose had no influence on VDBP in the diabetes group.&#x0D; Conclusion: Serum VDBP levels were significantly lower in T1DM patients but in this group, disease duration, insulin dose, and&#x0D; metabolic control did not affect serum VDBP levels. Serum VDBP concentrations in T1DM may be affected by other parameters rather&#x0D; than metabolic parameters. Therefore, future studies should focus on addressing this knowledge gap.