Vitamin D deficiency and C-reactive protein: a bidirectional Mendelian randomization study

Micronutrients, Vitamin D, and Inflammatory Biomarkers in COVID-19: A Systematic Review and Meta-analysis of Causal Inference Studies

CONTEXT

Experimental and observational studies suggest that circulating micronutrients, including vitamin D (VD), may increase COVID-19 risk and its associated outcomes. Mendelian randomization (MR) studies provide valuable insight into the causal relationship between an exposure and disease outcomes.

OBJECTIVES

The aim was to conduct a systematic review and meta-analysis of causal inference studies that apply MR approaches to assess the role of these micronutrients, particularly VD, in COVID-19 risk, infection severity, and related inflammatory markers.

DATA SOURCES

Searches (up to July 2023) were conducted in 4 databases.

DATA EXTRACTION AND ANALYSIS

The quality of the studies was evaluated based on the MR-STROBE guidelines. Random-effects meta-analyses were conducted where possible.

RESULTS

There were 28 studies (2 overlapped) including 12 on micronutrients (8 on VD) and COVID-19, 4 on micronutrients (all on VD) and inflammation, and 12 on inflammatory markers and COVID-19. Some of these studies reported significant causal associations between VD or other micronutrients (vitamin C, vitamin B6, iron, zinc, copper, selenium, and magnesium) and COVID-19 outcomes. Associations in terms of causality were also nonsignificant with regard to inflammation-related markers, except for VD levels below 25 nmol/L and C-reactive protein (CRP). Some studies reported causal associations between cytokines, angiotensin-converting enzyme 2 (ACE2), and other inflammatory markers and COVID-19. Pooled MR estimates showed that VD was not significantly associated with COVID-19 outcomes, whereas ACE2 increased COVID-19 risk (MR odds ratio = 1.10; 95% CI: 1.01-1.19) but did not affect hospitalization or severity of the disease. The methodological quality of the studies was high in 13 studies, despite the majority (n = 24) utilizing 2-sample MR and evaluated pleiotropy.

CONCLUSION

MR studies exhibited diversity in their approaches but do not support a causal link between VD/micronutrients and COVID-19 outcomes. Whether inflammation mediates the VD-COVID-19 relationship remains uncertain, and highlights the need to address this aspect in future MR studies exploring micronutrient associations with COVID-19 outcomes.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022328224.

High-dose vitamin D supplementation in pregnancy ameliorates obesity-induced increase in maternal IL-1β level without affecting obesity-induced increase in IL-6 and MCP

BACKGROUND

Maternal and placental inflammatory activity is carefully regulated during pregnancy and changes in inflammatory status are associated with pregnancy complications and health deficits in the offspring including adverse effects on neurodevelopment. Overweight/obesity is associated with chronic inflammation, thereby contributing to adverse effects. Disturbingly, overweight and obesity are highly prevalent among pregnant women worldwide. Vitamin D (vitD) possess immunomodulatory effects and is believed to support healthy pregnancy. Endocrinological societies recommend empiric vitD supplementation in pregnancy but there is no consensus on the minimal supplementation dose METHODS: An adjacent study to GRAVIT-D (no. NCT04291313, ClinicalTrial.gov), a double-blinded randomized trial investigating the clinical benefits of increasing vitD supplementation in pregnancy from 400IU to 3600IU/day from gestational week 11-16 onwards. In a subgroup, (n = 156), multiplex ELISA targeting third-semester serum levels of IL-1β, IL-6, IL-10, TNFα, MCP-1, and IL-17A was performed. Inflammation signals were correlated with the vitD dose given, subsequently analysing the effect of vitD in relation to the pre-pregnancy body mass index (BMI) within each treatment arm comparing the inflammatory response in WHO-defined BMI groups, < 25, 25-30 and > 30 kg/m2.

MAIN RESULTS

High pre-pregnancy BMI was associated with increased IL6 and MCP1 in both the 400IU and the 3600 IU exposed group. IL1β levels increased with BMI if using a 400IU/day supplement. High dose vitD supplementation ameliorated BMI effects on IL1β.

CONCLUSION AND PERSPECTIVES

Increased vitD supplementation during pregnancy may ameliorate some overweight/obesity-induced inflammatory activity. Further studies are needed to determine the vitD need in pregnancies complicated by obesity and overweight.

Construction of a nomogram for predicting serum vitamin D deficiency in children/adolescents with new-onset type 1 diabetes: a single-center study in China

Objective

The vitamin D-type 1 diabetes (T1D) association has been debated in public health. The purpose of this study was to develop a vitamin D deficiency prediction model and investigate vitamin D deficiency risk factors in children and adolescents with new-onset T1D.

Methods

A single-centre, retrospective analysis of paediatric patients (1-18 years) with new-onset T1D and initial 25-hydroxyvitamin D assessments was performed at a tertiary hospital in China between January 2020 and July 2024 (n = 353). The patients were divided into two groups according to whether their vitamin D deficiency exceeded 12 ng/ml. After identifying vitamin D deficiency risk factors in children/adolescents with new-onset T1D, a receiver operating characteristic (ROC) curve model was developed to predict the probability of vitamin D deficiency in these individuals. That model was represented with a nomogram. Calibration and clinical decision analysis curves were used to evaluate the model's effectiveness after internal validation via bootstrapping.

Results

The prevalence rate of serum vitamin D deficiency among patients with new-onset T1D was 26.35% (93/353). Multivariate logistic regression analysis revealed that minority status (X1), weight (X2), diabetic ketoacidosis severity (X3), serum vitamin D testing season (X4), free triiodothyronine (X5), and high-density lipoprotein (X6) were closely associated with serum vitamin D deficiency development in children/adolescents with new-onset T1D (P < 0.05). The model was logit (P) =ex/(1 + ex), X = 4.626-1.878*X1-0.038*X2-0.821*X3-0.88*X4 + 0.351*X5 + 0.532*X6. The area under the curve (AUC) of the serum vitamin D deficiency predictive model among patients with new-onset T1D was 0.769 (95% CI = 0.711-0.826). The predicted probability's best cut-off value was 0.671.

Conclusions

The established risk prediction model has good efficacy, providing a reference for screening high-risk vitamin D deficiency groups among children/adolescents with new-onset T1D and taking preventive and protective measures. The nomogram was developed based on a single-center cohort in China, and its generalizability needs further validation in more extensive populations.

Vitamin D Supplementation During Pregnancy and Maternal and Neonatal Vitamin D Status at ≤32 Weeks Gestation: Romanian Prospective Observational Cohort Study

Background: Recently, vitamin D deficiency (VDD) has been described as a pandemic, affecting all groups of the population. Pregnant women and preterm infants are particularly vulnerable to vitamin D deficiency. Objectives: We aimed to evaluate the maternal and neonatal vitamin D status in relation with maternal vitamin D supplementations during pregnancy and to identify demographic, social, and healthcare risk factors for maternal VDD and vitamin D insufficiency in women delivering at ≤32 weeks of gestation. Methods: This prospective observational study was developed in the regional level III maternity unit of the Clinical County Emergency Hospital Sibiu. It included all admitted mothers who delivered at ≤32 weeks of gestation and their infants between 1 March 2022 and 28 February 2025. Infant deaths in the first 24 h of life, major congenital defects, chromosomal abnormalities, the admission of outborn infants without their mothers, or the transfer of the mother more than 48 h after birth were used as exclusion criteria. Maternal and neonatal data were collected from medical records. Data on maternal vitamin D supplementation were collected through interviews. Univariate and multivariate logistic regressions, linear regression, and predictive models were performed for data analysis. Results: A total of 146 mothers (median (IQR) age 30 (24-35) years) and their 164 preterm infants born at ≤32 weeks of gestation (median gestational age of 30 (27-31) weeks and birth weight of 1200 (900-1527) g) were included in this study. Only 43.15% of the mothers used multivitamins containing vitamin D during pregnancy, and 10.96% used specific vitamin D supplements. Vitamin D supplementation was used for a median of 4 (3-5) months at a median dose of 800 (250-1500) IU/day. Severe VDD (25(OH)D < 10 ng/mL), VDD (25(OH)D < 20 ng/mL), VDI (25(OH)D 20-29 ng/mL) were found in 19.86%, 55.48%, and 23.97% of the mothers and 16.46%, 58.53%, and 25.61% of their infants, respectively. A significant correlation was found between the maternal and neonatal status (r = 0.684, r2 = 0.468, p < 0.001, B = 0.62). Both the maternal and neonatal vitamin D status were correlated with the vitamin D duration and dose used for supplementation during pregnancy. The logistic regression analysis showed that birth during a cold season and increased parity are independently associated with severe maternal VDD, while birth during the cold season and a lower educational status were independently associated with maternal VDD. Only an absent vitamin D supplementation (in the form of a multivitamin or specific vitamin D supplements) has been proven as an independent risk factor for VDI. Conclusions: Our findings revealed a worrisome prevalence of severe VDD, VDD, and VDI in mothers delivering very prematurely and in their infants. Additionally, less than half of the mothers in this study used vitamin D supplements during pregnancy despite the national recommendations. The professionals involved in advising pregnant women and policymakers should find solutions to improve the vitamin D status in these vulnerable groups of the population.

Interaction effects between serum 25(OH)D and CRP status on cancer related mortality in adult cancer survivors

Vitamin D deficiency and elevated CRP (C-reactive protein) levels are independent indicators of risk for mortality in cancer survivors; however, their combined association with mortality has not been examined. This study included adult cancer survivors from four NHANES cycles (2003-2010), utilizing a multistage survey design. CRP levels were measured using a latex-enhanced turbidimetric assay, and serum 25(OH)D levels were assessed using RIA and LC-MS/MS methods. Mortality data were linked with the National Death Index up to 2019. The restricted cubic spline model was used to explore the nonlinear associations with mortality. Kaplan-Meier analysis was used to examine survival curve differences. Cox analysis was employed to assess mortality risk after adjusting for confounding factors, and interaction analysis was conducted. Of the 1619 adult cancer survivors (56.9% female; weighted age 64.91 ± 0.44 years), 762 deaths were recorded during the 17-year follow-up. Higher CRP and lower 25(OH)D levels were associated with increased risks of all-cause and cancer mortality. Joint analysis revealed the High CRP and Low VID group had the highest all-cause (HR 2.40, 95% CI 1.82-3.17) and cancer (HR 5.23, 95% CI 3.15-8.70) mortality risk compared to Low CRP and High VID group. Additionally, a multiplicative interaction between serum 25(OH)D and CRP factors on cancer mortality was observed (P = 0.049), indicating a synergistic effect of these two factors on cancer mortality. Sex and ethnicity subgroup analyses revealed that the High CRP and Low VID group exhibits the highest risk for all-cause and cancer mortality, findings that are consistent with those observed in the overall population. In cancer survivors, an elevated risk of cancer and all-cause mortality is linked to vitamin D deficiency and elevated levels of CRP. In particular, the interaction between these factors may impact cancer survivors' mortality related to cancers. Consequently, the risks may be significantly reduced through the use of anti-inflammatory medications as well as adequate intake of vitamin D.

Association Between Low Blood 25-Hydroxyvitamin D and High C-Reactive Protein Levels in Community-Dwelling Japanese People Aged 40-74 Years

Low blood 25-hydroxyvitamin D (25[OH]D) levels at which C-reactive protein (CRP) levels begin to rise vary. This study investigated the association between blood 25(OH)D and elevated CRP levels and determine the cut-off of low 25(OH)D for elevated CRP in middle-aged and older individuals in the Murakami cohort, Japan. This study used a cross-sectional study design with 2,863 subjects aged 40-74 years living in the community. Plasma 25(OH)D levels were determined with the Liaison® 25OH Vitamin D Total Assay, and serum high sensitivity CRP (hs-CRP) levels were determined with a latex nephelometry assay using an automatic analyzer. Multivariate logistic regression analysis was used to calculate odds ratios (ORs) for high hs-CRP (≥ 3 mg/L) with covariates including sex, age, BMI, physical activity, smoking, drinking, and disease history. Median age of subjects was 65 years, and median 25(OH)D level was 47.4 nmol/L. The proportion of subjects with high hs-CRP levels was 4.1%. The adjusted OR of 25(OH)D < 20 nmol/L was higher (OR = 3.22, 95% CI: 1.42-7.31) than that of the reference (25[OH]D 40-49 nmol/L). In subgroup analysis, the adjusted OR of 25(OH)D < 20 nmol/L was significantly higher than the reference in the BMI ≥ 22.8 (median) group (OR = 4.52) but not in the BMI < 22.8 group (OR = 1.61) (P for interaction = 0.0892), and the adjusted OR was significantly higher in the age ≥ 65 group (OR = 8.51) but not in the age < 65 group (OR = 2.22). Low blood 25(OH)D and high CRP levels were associated, with 25(OH)D 20 nmol/L being the cut-off, which was lower than previously reported values.

Exploring the Link Between C-Reactive Protein Change and Stroke Risk: Insights From a Prospective Cohort Study and Genetic Evidence

BACKGROUND

Previous research on how changes in CRP (C-reactive protein) levels predict stroke risk is limited. This study aimed to examine the association between CRP change and the risk of stroke and its subtypes.

METHODS AND RESULTS

Based on the UK Biobank data, we investigated the association between CRP change and the risk of stroke and its subtypes with Cox proportional hazards regression analysis. We further performed genetic analyses including genetic correlation, pairwise genome-wide association study, and polygenic risk score. Our study involved 14 754 participants with a median follow-up time of 10.4 years. After categorizing participants by CRP percentage change and making adjustments for potential confounders, it was observed that those with an elevated percentage of CRP change had a higher risk of any stroke (hazard ratio [HR], 1.44 [95% CI, 1.12-1.85]) and ischemic stroke (HR, 1.65 [95% CI, 1.24-2.18]). After categorization by CRP change types and adjustment for confounders, the group that became high level had a higher any-stroke risk (HR, 1.45 [95% CI, 1.04-2.02]), with the group that remained at a high level facing the greatest risk (HR, 1.74 [95% CI, 1.30-2.33]). Similar trends were observed for ischemic stroke. The group that remained at a high level also had a heightened hemorrhagic stroke risk (HR, 1.91 [95% CI, 1.07-3.44]). Genetic analysis showed a significant genetic correlation between CRP and stroke (rg, 0.257; rg_P=2.39E-07). Pairwise genome-wide association study analysis identified 5 shared genomic regions between CRP and stroke. Polygenic risk score analysis showed that participants with high stroke polygenic risk score and elevated or remaining high CRP levels have the highest risk of stroke.

CONCLUSIONS

Both any stroke and ischemic stroke are related to elevated and remaining high CRP levels, while hemorrhagic stroke is only related to remaining high CRP levels.

Associations between serum micronutrients and all-cause, cancer, and cardiovascular mortality in a national representative population: Mediated by inflammatory biomarkers

BACKGROUND

Micronutrient intake was inversely associated with cancer and cardiovascular risk in previous studies, but obtained results were inconsistent and the biological mechanisms for this potential protective effect remain elusive. Therefore, we investigated the associations of serum vitamin C, 25(OH)D, α-tocopherol, β-carotene, lycopene, folate, and iron with all-cause, cancer, and cardiovascular mortality. We further evaluated whether these associations were mediated through altered inflammatory responses.

METHODS

Data were obtained from 11,539 participants aged ≥40 years in the National Health and Nutrition Examination Survey (NHANES) in 2001-2006 and 2017-2018. Mortality status of the participants with an average follow-up of 10.5 years was ascertained from the linked mortality files of the National Death Index. Cox proportional hazards regression was performed to evaluate mortality risk in relation to serum micronutrients, while mediation analysis was used to assess the mediating effects of serum C-reactive protein and white blood cell count on the associations of interest.

RESULTS

After adjustment for confounders, serum levels of vitamin C, 25(OH)D, β-carotene, and lycopene were associated with a reduced risk of death from all causes, cancer, and cardiovascular disease. For example, HRs (95 % CIs) for quartiles 2, 3, and 4 vs. quartile 1 of 25(OH)D were, respectively, 0.72 (0.62, 0.83), 0.70 (0.62, 0.79), and 0.66 (0.56, 0.78) (p-trend: <0.0001) for all-cause mortality, 0.68 (0.52, 0.91), 0.54 (0.39, 0.73), and 0.48 (0.32, 0.71) (p-trend: 0.0001) for cancer mortality, and 0.64 (0.50, 0.83), 0.66 (0.53, 0.83), and 0.59 (0.42, 0.82) (p-trend: 0.0012) for cardiovascular mortality. Additionally, serum C-reactive protein significantly mediated 5.3%-20.4 %, 4.5%-18.1 %, and 3.3%-15.7 % of the associations of vitamin C, 25(OH)D, β-carotene, and lycopene with all-cause, cancer, and cardiovascular mortality, respectively.

CONCLUSION

This study suggested that serum levels of several antioxidants and vitamin D were inversely associated with all-cause, cancer, and cardiovascular mortality, mediated in part by mitigated inflammatory responses.

Vitamin D status in children undergoing allogeneic hematopoietic stem cell transplantation: A prospective exploratory study

OBJECTIVES

Allogeneic hematopoietic stem cell transplantation (HSCT) is associated with nutritional risks. This study describes vitamin D status and intake in children undergoing HSCT and compares results to healthy children.

METHODS

In a prospective observational study, vitamin 25(OH)D and 1,25(OH)2D were assessed at hospital admission before HSCT (baseline), at 3-month and 1-year post-transplant. Vitamin D deficiency was defined as 25(OH)D < 50 nmol/L. A 4-day diet record assessed vitamin D intake at 3-months and 1-year. Healthy children were assessed once.

RESULTS

Twenty-eight HSCT patients (mean age: 10.3-years, standard deviation [SD]: 4.0) and 50 healthy children (mean age: 10.0-years, SD: 3.6) were included. Vitamin D deficiency was more prevalent in patients at baseline (36%, p < 0.001) and 3-months (24%, p = 0.007) but not at 1-year (14%, p = 0.084) than in healthy children (2%). Median 1,25(OH)2D was significantly lower than in healthy children at the two first visits (p < 0.001) but not at 1-year (p = 0.198). Median vitamin D provision was higher at 3-months (18.1 µg/day) and 1-year (25 µg/day) compared to healthy children (5.3 µg/day, p < 0.001).

CONCLUSIONS

Children undergoing HSCT were at a high risk of vitamin D deficiency at baseline and 3-month post-transplant, but not at 1-year compared to healthy children. Vitamin D intake was higher after transplantation than in healthy children. These findings indicate that vitamin D requirements are elevated in HSCT patients, emphasizing the need for monitoring and adequate supplementation.

TRIAL REGISTRATION

Clinical Trials AEV2017/1. 2016/391/REK sør-øst B.

Application of Mendelian randomized analysis method in Vitamin D research: A 10-year bibliometric analysis

Vitamin D is an open-cyclic steroidal trace organic compound that plays a crucial role in human metabolism and nutritional health. In recent years, Mendelian randomization (MR) has emerged as a widely adopted method for analyzing causal relationships, particularly in studying the association between Vitamin D and related diseases. However, no bibliometric analyses have been conducted to explore the research hotspots and trends regarding Vitamin D status in MR studies. This study utilized the Web of Science Core Collection as a source database and retrieved articles on Vitamin D status in MR published from 2014 to 2024. Bibliometric and visualization analyses utilized VOSviewer, Microsoft Excel 2021, and Scimago Graphica. An in-depth analysis of country or region, authors, journals, keywords, and references were performed to provide insights into the content related to the field. A total of 186 documents authored by 1122 contributors across 30 countries were identified. China and the University of Bristol had the highest publication counts, with 94 and 19 articles, respectively. The nutrients published the largest number of articles, and J Brent Richards was the largest contributors. The most frequently used keywords included "Mendelian randomization," "Vitamin D," "25-hydroxyVitamin D," "obesity," and "Type 2 Diabetes." The current research focuses on using MR methods to explore the associations between Vitamin D status and metabolic, cardiovascular, immune skin, psychiatric and neurological diseases. The related research in this field will continue to increase in the next few years, which is a promising research prospect in this field. This study systematically reviews the literature from the past decade, revealing research hotspots and trends in the field of Vitamin D status within MR studies. This information will provide a strong reference for readers and researchers.

High prevalence of low vitamin D status in the Czech Republic: a retrospective study of 119,925 participants

OBJECTIVES

Given the high worldwide prevalence of vitamin D deficiency and its role in numerous diseases affecting mortality and morbidity, this study seeks to determine the prevalence of low 25-hydroxyvitamin D levels in the Czech Republic, where population-level data are currently lacking.

STUDY DESIGN

This retrospective study utilized a large dataset to analyze 25-hydroxyvitamin D levels over an extended period.

METHODS

We analyzed data from 119,925 individuals aged 0-100 years categorizing them as sufficient (75-250 nmol/L), insufficient (50-75 nmol/L), or deficient (<50 nmol/L). We also examined levels of CRP, homocysteine, and their correlations with 25-hydroxyvitamin D levels across age groups. Age, sex, sampling month, sunlight exposure (monthly and annual), and influenza virus positivity were assessed for their relationship with the 25-hydroxyvitamin D levels.

RESULTS

The study found a high prevalence of 25-hydroxyvitamin D inadequacy, with sufficient levels observed in 65.6% of infants (0-12 months). The lowest prevalence of sufficiency was in the 6-15 years (19.2%) and 16-30 years (22.1%) groups. The highest deficiency prevalence was in the 91-100 years group (51.8%). 25-hydroxyvitamin D levels in all age groups and both sexes correlated with all selected parameters. Lower sun exposure, higher flu virus positivity, male gender, and elevated homocysteine and CRP levels were negatively correlated with 25-hydroxyvitamin D levels.

CONCLUSIONS

The prevalence of 25-hydroxyvitamin D inadequacy in the Czech Republic is high. It is advisable to consider testing, monitoring, and providing medical recommendations for vitamin D supplementation as part of health prevention strategies in the general population.

Exploring Interaction between Genetically Predicted Body Mass Index and Serum 25-Hydroxyvitamin D Levels on the Odds for Psoriasis in UK Biobank and the HUNT Study: A Factorial Mendelian Randomization Study

Mendelian randomization (MR) studies show that higher body mass index (BMI) and lower 25-hydroxyvitamin D (25[OH]D) increase psoriasis risk. The combined effect of these factors has not been explored using factorial MR. Using cross-sectional data from UK Biobank (n = 398,404) and The Trøndelag Health Study (n = 86,648), we calculated polygenic risk scores for BMI and 25(OH)D to estimate ORs for psoriasis using 2 × 2 and continuous factorial MR. We quantified additive interaction by estimating relative excess risk due to interaction. We also performed traditional observational analyses in UK Biobank. There were 12,207 (3.1%) participants with psoriasis in UK Biobank and 7794 (9.0%) in The Trøndelag Health Study. In 2 × 2 factorial MR, we found no evidence of relative excess risk for psoriasis due to interaction between genetically predicted higher BMI and lower 25(OH)D, neither in UK Biobank (relative excess risk due to interaction = -0.01, 95% confidence interval = -0.08 to 0.07) nor in The Trøndelag Health Study (relative excess risk due to interaction = -0.04, 95% confidence interval = -0.14 to 0.06). The same was observed in the continuous factorial MR and observational analyses. In conclusion, this study did not find evidence of interaction between BMI and 25(OH)D on the risk of psoriasis. Given minor differences in measured BMI and 25(OH)D between the factorial groups, small effects may have been undetected.

Association of Preoperative Serum 25-Hydroxyvitamin D with Longitudinal Body Mass Index After Bariatric Surgery-A Mediation Effect of Serum Albumin

BACKGROUND

The predictive ability of vitamin D for weight loss after bariatric surgery is not well-characterized. This prospective cohort study assessed the utility of preoperative serum 25-hydroxyvitamin D (25(OH)D) as a predictor of body mass index (BMI) at follow-up after bariatric surgery. Additionally, the mediation role of serum albumin was explored.

METHODS

Patients scheduled for bariatric surgery were recruited from a single center. The final analyzed cohort consisted of 316 subjects (age, 40 ± 10 years; 35.4% males; BMI, 42.6 ± 7.2 kg/m2). The associations between preoperative 25(OH)D and baseline (pre-surgery) BMI or repeated measures of BMI collected at baseline, and 3-, 6-, and 12-month post-surgery were examined using linear regression or linear mixed model, respectively. The mediation effect of baseline albumin was evaluated using mediation analysis.

RESULTS

Before surgery, 98.5% of patients had vitamin D insufficiency (25(OH)D < 30 μg/L). Baseline BMI elevated progressively as severity of vitamin D insufficiency increased (P-trend = 0.025). Lower 25(OH)D levels were independently associated with higher preoperative BMI (coefficient, - 0.20; 95% CI, - 0.32 to - 0.08; P = 0.001) or less BMI reduction at follow-up (coefficient, - 0.15; 95% CI, - 0.25 to - 0.04; P = 0.007), after adjustment for baseline demographics, diabetes status, and/or surgical procedure. The association diminished after accounting for albumin, which emerged as a significant determinant (coefficient, - 0.61; 95% CI, - 0.83 to - 0.40; P < 0.001). Mediation analysis showed that reduced albumin explained 30% (P < 0.001) of the relationship between 25(OH)D and longitudinal BMI.

CONCLUSIONS

Lower preoperative 25(OH)D is associated with less BMI reduction over 1-year follow-up after bariatric surgery, potentially mediated by reduced serum albumin.

Exploring Causal Associations Between Serum Inflammatory Markers and Female Reproductive Disorders: A Mendelian Randomisation Study

Although inflammation may disrupt immunoendocrine crosstalk essential for female reproductive function, causal links to disorders like polycystic ovary syndrome (PCOS) and endometriosis remain unestablished. This study aimed to utilise Mendelian randomisation (MR) methods to explore causal associations between serum inflammatory markers and common reproductive disorders, aiming to identify novel mechanisms and potential avenues for treatment. Total causal effects of serum inflammatory markers (interleukins, monocyte chemoattractant protein-1, etc.) on female reproductive disorders in large sample cohorts of Finnish ancestry were assessed using univariable two-sample MR methods, including the inverse variance weighted (IVW) method as the primary analysis, with relevant quality assessments (e.g., leave-one out, heterogeneity, and horizontal pleiotropy testing). The main outcome measures were PCOS (642 cases and 118,228 controls) and endometriosis (8288 cases and 68,969 controls) from the FINNGEN cohort. Monocyte chemoattractant protein-1/C-C motif chemokine ligand demonstrated a positive causal association with polycystic ovary syndrome (odds ratio [95% CI]: 1.48 [1.10, 2.00], p = 0.0097), while higher interleukin-9 levels were positively associated with endometriosis (1.15 [1.02, 1.30], p = 0.0277), both via the IVW method. These markers should be investigated as key candidates for future research into the mechanistic pathways underpinning these conditions.

Vitamin D and cardiovascular outcomes in multiple sclerosis

BACKGROUND

Vitamin D (25(OH)D) deficiency is linked to increased cardiovascular disease (CVD) risk in the general population, but its implications for people with multiple sclerosis (pwMS) remain unexplored. This study aimed to evaluate the association of 25(OH)D with long-term CVD outcomes in pwMS and the impact of vitamin D supplementation.

METHODS

This observational cohort study analysed anonymised medical records from 70 healthcare organisations following pwMS for 5-years (2019-2024). PwMS and deficient or inadequate 25(OH)D levels were 1:1 propensity-score matched with pwMS and adequate 25(OH)D levels, for demographics, comorbidities, and cardiovascular care. Cox proportional hazard models analysed the incidence of all-cause mortality, stroke, acute myocardial infarction, heart failure, angina, atrial fibrillation/flutter, and a composite measure of major adverse cardiovascular events (MACE). Propensity-matched pwMS who had deficient or inadequate 25(OH)D levels taking cholecalciferol were compared to pwMS and adequate 25(OH)D levels (not taking supplementation).

RESULTS

Amongst 74,372 pwMS, 9 % had deficient 25(OH)D levels, 18 % inadequate, and 73 % adequate. Deficient, or inadequate 25(OH)D levels were associated with an increased rate of MACE (HR, 1.32 [95 % CI: 1.19, 1.46], HR, 1.29 [95 % CI: 1.20, 1.40], respectively) compared to those with adequate levels. Cholecalciferol supplementation in pwMS and deficient or inadequate 25(OH)D levels did not alleviate the higher CVD rate (HR, 1.39 [95 % CI: 1.21,1.60], HR, 1.31 [95 % CI: 1.17, 1.47], respectively) in comparison to those with adequate 25(OH)D levels taking no vitamin D supplementation.

CONCLUSIONS

Deficient or inadequate 25(OH)D levels in pwMS were associated with an increased rate of MACE, which may not be mitigated by vitamin D supplementation.

Causal Relationships Between Epilepsy, Anti-Epileptic Drugs, and Serum Vitamin D and Vitamin D Binding Protein: A Bidirectional and Drug Target Mendelian Randomization Study

AIMS

Previous studies suggest potential associations between epilepsy, anti-epileptic drugs (AEDs), and levels of vitamin D and vitamin D-binding protein (VDBP). This study aims to investigate the causal relationships among these variables using Mendelian Randomization (MR) methods.

METHODS

Using summary data from genome-wide association studies on serum 25-hydroxyvitamin D [25(OH)D] levels (N = 417,580), VDBP concentrations (N = 65,589), and various types of epilepsy (Ncases = 27,559), MR analyses were conducted to determine bidirectional causal relationships among these variables. Additionally, eQTL data from eQTLGen (N = 31,684) were employed to model the effects of AEDs and evaluate their causal impact on both biomarkers.

RESULTS

No causal relationships were found between serum 25(OH)D or VDBP levels and epilepsy. Although genetically predicted focal epilepsy risk was potentially associated with increased serum 25(OH)D levels (OR 1.031, 95% CI: 1.006-1.058, p = 0.017), and a higher genetic risk of juvenile myoclonic epilepsy was linked to lower VDBP levels (OR 0.977, 95% CI: 0.961-0.993, p = 0.004), both associations lost significance after multiple correction. Furthermore, significant associations were observed between serum 25(OH)D levels and AED target genes SCN4A, GABBR1, CA13, ALDH5A1, and CA8. No significant associations were found between AED target genes and VDBP levels after correction.

CONCLUSION

No causal relationships were found between genetically determined serum 25(OH)D levels, VDBP, and epilepsy or its subtypes. Furthermore, the use of AEDs, such as Carbamazepine, Oxcarbazepine, Progabide, and Valproic Acid, reduces serum 25(OH)D levels, while not affect VDBP levels.

The Immunomodulatory Role of Vitamin D in Regulating the Th17/Treg Balance and Epithelial-Mesenchymal Transition: A Hypothesis for Gallbladder Cancer

The etiology of gallbladder cancer (GBC) is multifactorial, with chronic inflammation resulting from infections, autoimmune diseases, and lifestyle factors playing a pivotal role. Vitamin D deficiency (VDD) has been implicated in the pathogenesis of autoimmune disorders and various malignancies, including GBC. Research on autoimmune diseases highlights the anti-inflammatory properties of vitamin D, suggesting its potential to mitigate disease progression. In oncology, VDD has similarly been linked to increased inflammation, which may contribute to both the initiation and progression of cancer. A critical component in carcinogenesis, as well as in the immunomodulatory effects of vitamin D in autoimmune conditions, is the balance between T-helper 17 (Th17) cells and regulatory T (Treg) cells. We hypothesize that vitamin D may inhibit epithelial-mesenchymal transition (EMT) in GBC by modulating the spatial distribution of tumor-infiltrating T cells, particularly through the regulation of the Th17/Treg balance at the tumor margins. This Th17/Treg imbalance may act as a mechanistic link between VDD and the progression of GBC carcinogenesis. Investigating the role of an Th17/Treg imbalance as a mediator in VDD-induced EMT in GBC not only provides deeper insights into the pathogenesis of GBC but also sheds light on broader mechanisms relevant to the development of other solid organ cancers, given the expanding recognition of the roles of VDD and Th17/Treg cells in cancer biology.

Association of fish intake with all-cause mortality according to CRP levels or inflammation in older adults: a prospective cohort study

BACKGROUND

The relationship between inflammatory response, fish consumption, and mortality risk in older individuals is unclear. We investigated whether C-reactive protein (CRP) levels ≥ 0.1 mg/dL, fish intake, and inflammatory responses are associated with all-cause mortality risk in older adults.

METHODS

This prospective cohort study included older adults aged 85-89 years from the Kawasaki Aging and Wellbeing Project, who did not require daily care. Cohort was recruited from March 2017 to December 2018 (follow-up ended on December 31, 2021). Dietary assessment was conducted using the Brief Self-Administered Diet History Questionnaire. Multivariate Cox proportional hazards regression was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) for all-cause mortality in the CRP ≥ 0.1 mg/dL group; the CRP < 0.1 mg/dL group was used for reference. Within CRP ≥ 0.1 and < 0.1 mg/dL groups, participants were categorized into tertiles of fish intake. HRs and 95% CIs for all-cause mortality in the other groups were estimated using the lower tertile group as a reference.

RESULTS

The study included 996 participants (mean [standard deviation] age, 86.5 [1.37] years; 497 [49.9%] women) with a median CRP level of 0.08 (interquartile range [IQR] = 0.04-0.16). There were 162 deaths during 4,161 person-years of observation; the multivariable-adjusted HR for all-cause mortality in the CRP ≥ 0.1 mg/dL group was 1.86 (95% CI, 1.32-2.62); P < 0.001. In 577 individuals with median (IQR) fish intake of 39.3 g/1000 kcal (23.6-57.6) and CRP level of < 0.1 mg/dL, the multivariable-adjusted HR for all-cause mortality in the higher tertile group of fish intake was 1.15 (0.67-1.97); P = 0.59, non-linear P = 0.84. In 419 individuals with median (IQR) fish intake of 40.7 g/1000 kcal (25.0-60.1) and CRP level of ≥ 0.1 mg/dL, the multivariate-adjusted HR for all-cause mortality in the higher tertile group of fish intake was 0.49 (0.26-0.92); P = 0.026, non-linear P = 0.38, P-value for interaction = 0.040.

CONCLUSIONS

A negative association between fish intake and all-cause mortality was seen in older adults with elevated CRP levels, which is a mortality risk factor. While the results may be limited owing to stringent methods ensuring impartiality, they offer valuable insights for future research.

TRIAL REGISTRATION

UMIN000026053. Registered February 24, 2017.

Acute phase proteins patterns as biomarkers in bacterial infection: Recent insights

Escherichia coli is a bacterium with command and pathogenic variants. It has been implicated in the induction of several inflammatory conditions. Finding a biomarker for infection began many years ago. The challenge of using acute phase proteins (APPs) as biomarkers for infection is a promising target for many researchers in this field. Many APPs have been studied for their roles as biomarkers of E. coli infection. The following review aims to highlight recent trials that have approved the use of adiponectin, amyloid A, ceruloplasmin, C-reactive protein, Haptoglobin, and Pentraxin 3 as biomarkers for E. coli infection and assess the obtained results. In conclusion, despite the existing approaches for the use of APPs as biomarkers in E. coli infection, we recommend more precise studies to enable these markers to be more specific and applicable in clinical fields. APPs could be markers for systemic inflammatory conditions, regardless of the causative agent.

The Effect of Vitamin D Deficiency Treatment on Lipid Profile and C-reactive Protein in Patients with Ischemic Heart Disease: Double-blind Randomized Clinical Trial

Background

Atherosclerosis is the main process in coronary artery stenosis, which is exacerbated by vitamin D deficiency. This study aims to investigate the relationship between vitamin D deficiency treatment, lipid profile, and C-reactive protein (CRP) in ischemic heart disease (IHD).

Materials and Methods

This is a double-blind, randomized clinical trial involving 44 IHD patients with hypovitaminosis, aged 40-65 years, who were referred to Chamran Specialty Heart Hospital, Isfahan, Iran. Participants were randomly divided into two groups: The intervention group received weekly doses of 50,000 units of vitamin D3 for 5 weeks, while the placebo group received a control substance. CRP and serum lipid profiles, including total cholesterol (TC), triglycerides (TGs), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), were assessed before and after the intervention. Trial registration number: IRCT20200905048622N1.

Results

The mean age of the IHD patients was 57.84 ± 9.66 years, and among all 44 patients, 40 patients (91%) were male In the intervention group receiving vitamin D3, serum levels of HDL (P = 0.048) and 25-hydroxyvitamin D (25(OH)D) (P < 0.001) increased, while serum level of TG (P = 0.008) decreased significantly. In the placebo group, HDL level (P = 0.007) was increased and alanine transaminase (ALT) (P = 0.05) was significantly decreased. The results showed that the correlation between serum 25(OH)D treatment and CRP level was not significant.

Conclusion

Vitamin D supplementation in IHD patients led to notable improvements in lipid profiles, including increased HDL-C levels and decreased TG levels. These findings hold potential clinical implications for healthcare professionals in managing risk factors in IHD patients.

Associations Between Early-Pregnancy Vitamin D Status and Postpartum Depressive and Anxiety Symptoms

OBJECTIVE

Maternal postpartum depressive and anxiety symptoms are risk factors for subsequent maternal and child mental health problems. Little is known about the potential role of antepartum vitamin D and C-reactive protein (CRP) in the etiology of maternal postpartum affective symptoms. We investigated associations between antepartum vitamin D status and postpartum depressive and anxiety symptoms and whether antepartum CRP mediated these associations.

METHODS

In 2483 participants of the Amsterdam Born Children and their Development prospective cohort, maternal serum vitamin D and CRP were measured at a median of 13 weeks' gestation. Vitamin D status was defined as deficient (≤29.9 nM), insufficient (30-49.9 nM), sufficient (50-79.9 nM), or normal (≥80 nM). Maternal depressive symptoms (Center for Epidemiologic Studies-Depression) and anxiety (State-Trait Anxiety Inventory) were assessed 3 months postpartum.

RESULTS

After adjustments for confounders, vitamin D deficiency was only associated with increased postpartum anxiety symptoms ( B = 0.17, 95% confidence interval [CI] = 0.03-0.30, p = .017) compared to normal vitamin D levels (≥80 nM). In women not taking vitamin D supplementation ( n = 2303), vitamin D deficiency was associated with increased postpartum depressive and anxiety symptoms ( B = 0.14, 95% CI = 0.03-0.28, p = .045; and B = 0.17, 95% CI = 0.03-0.32, p = .015). Antepartum CRP did not mediate these links.

CONCLUSIONS

We found some evidence that antepartum vitamin D deficiency was associated with increased postpartum affective symptoms, especially in women not taking vitamin D supplementation. Clinical trials should determine whether vitamin D supplementation can reduce the risk for postpartum affective disorders.

The interplay between vitamin D status, subclinical inflammation, and prediabetes

Vitamin D's role extends beyond classical calcium and phosphate homeostasis to encompass a pivotal influence on immune modulation and metabolic health. The mechanisms by which vitamin D exerts these effects involve its conversion to hormonally active calcitriol, which binds intracellular vitamin D receptors, initiating various downstream cascades. In this review, we tease out the evidence showing the relationship between vitamin D deficiency and prediabetes within the context of subclinical inflammation, with a special focus on the novel monocyte-to-HDL ratio (MHR), a novel inflammatory marker reflecting subclinical inflammation. This was based on a thorough literature review using reputable databases covering the period from 1980 to 2024. In light of this, we discuss calcitriol's anti-inflammatory effects and consequently link vitamin D deficiency to both overt and subclinical inflammation. Additionally, the utility of several biomarkers, notably MHR, in investigating this association is also discussed. We further reviewed the role of vitamin D deficiency in precipitating prediabetes and type 2 diabetes mellitus (T2DM) via insulin resistance, decreased insulin synthesis and secretion, and subclinical inflammation. Taken together, this mini review highlights that vitamin D deficiency is significantly associated with subclinical inflammation, playing a critical role in the development of prediabetes and the progression to T2DM. Addressing vitamin D deficiency through appropriate interventions may serve as a preventative measure against the development of prediabetes and T2DM.

The Impact of Environmental Factors on the Development of Autoimmune Thyroiditis-Review

Autoimmune thyroiditis (Hashimoto's thyroiditis) is the most common autoimmune disease. It most often manifests itself as hypothyroidism but may also present with euthyroidism or even hyperthyroidism. The etiopathogenesis of autoimmune thyroiditis is still unclear. However, in addition to genetic and epigenetic factors, many environmental factors are known to increase the risk of developing AIT. In this review, we aimed to collect and analyze data connected with environmental factors and autoimmune thyroiditis development. Our review indicates iodine intake, vitamin D deficiency, selenium deficiency, viral infections caused by Epstein-Barr Virus (EBV), Human parvovirus B19 (PVB19), Human herpesvirus 6A (HHV-6A) and Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), bacterial infection caused by Helicobacter pylori, microbiome disruption, medications such as interferon-alpha and tyrosine kinase inhibitors, as well as stress, climate, and smoking can influence the risk of the occurrence of autoimmune thyroiditis. Having knowledge of risk factors allows for making changes to one's diet and lifestyle that will reduce the risk of developing the disease and alleviate the course of autoimmune thyroiditis.

Dietary inflammatory index, mediating biomarkers and incident frailty in Chinese community-dwelling older adults

OBJECTIVES

Diet can modulate systemic inflammation, while inflammation is a critical contributory factor of frailty. However, longitudinal data on the association between dietary inflammatory index (DII) and frailty are limited, and the intermediate mechanisms remain unclear. This study aimed to examine the association between DII and incident frailty and the potential mediating roles of frailty-related biomarkers.

DESIGN

Prospective cohort study.

SETTING

The Mr. OS and Ms. OS (Hong Kong) study.

PARTICIPANTS

A total of 3,035 community-dwelling men and women aged above 65 years without frailty at baseline were included.

MEASUREMENTS

DII scores were calculated using the locally validated food frequency questionnaire. Incident frailty at year four was defined using the Fried frailty phenotype. Logistic regression was used to examine the association between DII and frailty onset. Mediation analysis was used to explore the mediating roles of frailty-related biomarkers in the DII-frailty association.

RESULTS

During four years of follow-up, 208 individuals developed frailty. Compared with the lowest tertile of DII, the highest tertile was associated with an increased risk of incident frailty (OR: 1.82; 95% CI: 1.17-2.82; p = 0.008) after adjustment for relevant confounders. The DII-frailty association was significant in men but not in women. Furthermore, increasing serum homocysteine, decreasing serum folate, and reducing estimated glomerular filtration rate (eGFR) mediated 11.6%, 7.1%, and 9.6 % of the total relation between DII and frailty onset, respectively.

CONCLUSION

In this cohort study, a pro-inflammatory diet was associated with a higher risk of frailty onset, mediated by homocysteine, folate, and renal function.

Vitamin D deficiency and increased inflammatory factor intercellular cell adhesion molecule-1 indicate severe leukoaraiosis in northern China

Background and objective

Commonly plaguing in the frigid zone of the world, vitamin D deficiency, as indicated by low levels of 25-hydroxyvitamin D, exacerbated inflammatory responses and impaired endothelial function. Leukoaraiosis (LA) is a prevalent cause of cognitive dysfunction in the elderly and is potentially associated with inflammatory responses. This study aimed to investigate the impact of vitamin D on the severity of LA.

Methods

Patients with LA were categorized based on 3.0 T brain MRI findings into mild (N = 43), moderate (N = 40), or severe groups (N = 29) using the Fazekas scale (scoring 1-6). A control group consisting of 41 healthy individuals was included. Serum fibrinogen C, homocysteine, plasma 25-hydroxyvitamin D, and intercellular cell adhesion molecule-1 (ICAM-1) levels were measured using ELISA.

Results

All LA severity groups exhibited lower plasma 25-hydroxyvitamin D levels compared to the control group, with a more pronounced decrease observed as LA severity increased. Low plasma 25-hydroxyvitamin D was identified as an independent risk factor for LA (P < 0.05) according to Multiple logistic regression analysis. Additionally, a negative association was observed between 25-hydroxyvitamin D and vascular inflammatory factor ICAM-1.

Conclusions

Disease severity positively correlated with levels of the inflammatory marker ICAM-1, worsening as plasma 25-hydroxyvitamin D concentration decreased. Low 25-hydroxyvitamin D emerged as an independent risk factor for LA, potentially exacerbating the inflammatory response. These findings suggest 25-hydroxyvitamin D supplementation as a potential therapeutic approach for LA.

Serum 25-hydroxyvitamin D level and erectile dysfunction: a causal relationship? Findings from a two-sample Mendelian randomization study

Background

Serum 25-hydroxyvitamin D level is associated with erectile dysfunction (ED) in observational studies. However, whether there is a causal association between them remains uncertain.

Objective

Conduct a two-sample Mendelian randomization (MR) analysis to investigate the causal effect between serum 25-hydroxyvitamin D level and ED risk.

Method

Genome-wide association study (GWAS) data of serum 25-hydroxyvitamin D levels comprising 6,896,093 single nucleotide polymorphisms (SNP) from 496,949 people of European ancestry were regarded as exposure for the MR analysis. Additional GWAS data involving 9,310,196 SNPs of 6,175 European ED cases and 217,630 controls were used as outcome data. The MR-Egger, inverse variance weighted (IVW) method, weighted median, simple mode, and weighted mode were employed to evaluate causal effects, among which IVW was the primary MR analysis method. The stability of the MR analysis results was confirmed by a heterogeneity test, a horizontal pleiotropy test, and the leave-one-out method.

Result

There were 103 SNPs utilized as instrumental variables (p < 5 × 10-8). The results of MR analysis showed no causal effects of serum 25(OH) D concentration on ED risks (IVW; OR = 0.9516, 95% CI = 0.7994 to 1.1328, p = 0.5772). There was no heterogeneity and pleiotropy in the statistical models.

Conclusion

The present MR study did not support a causal association for genetically predicted serum 25-hydroxyvitamin D concentration in the risk of ED in individuals of European descent.

Vitamin D deficiency and inflammatory markers in type 2 diabetes: Big data insights

The objective of this study was to investigate the prevalence of vitamin D deficiency or insufficiency and its association with inflammatory markers and type 2 diabetes. We conducted our research at Qingdao Endocrine and Diabetes Hospital, where serum 25-hydroxyvitamin D3 levels were determined for 2,806 individuals with type 2 diabetes aged 30 and older between January 2018 and December 2019. Medical records were analyzed, and data on health, blood lipids, HbA1c, and inflammation were collected. Our results revealed a high prevalence of vitamin D deficiency in the population. Among male and female patients, median serum 25(OH)D3 levels were 22.46 and 19.00 ng/mL, respectively. More than 60% of female patients had vitamin D deficiency, with over 80% having levels below 30 ng/mL. We observed a favorable connection between high-density lipoprotein cholesterol and 25(OH)D3, while triglycerides and HbA1c showed negative correlations. As 25(OH)D3 levels increased, inflammatory markers such as hypersensitive C-reactive protein (hsCRP), erythrocyte sedimentation rate (ESR), white blood cell count, neutrophil count, and monocyte count decreased (trend test, p < 0.05), although peripheral blood lymphocytes initially increased and then decreased. After controlling for age and gender, multiple linear regression analysis indicated negative correlations between ESR, hsCRP, and white blood cell count with 25(OH)D3 (p < 0.05). In conclusion, our study demonstrates that individuals with type 2 diabetes often exhibit vitamin D deficiency or insufficiency, which is associated with elevated levels of inflammatory markers in the blood.

Association Between Adequate Serum 25(OH)D Levels and Atherogenic Dyslipidemia in Young Adults

AIM

This study aimed to investigate the association between vitamin D deficiency and novel biomarkers of atherogenic dyslipidemia among young adults.

METHOD

A total of 976 young adults were recruited between 2011 and 2019. Their serum 25(OH)D levels were measured, and lipid profile markers, including low-density lipoprotein cholesterol (LDL-C), low-density lipoprotein triglyceride (LDL-TG), and small-dense low-density lipoprotein cholesterol (sdLDL-C), were assessed as novel biomarkers of atherogenic dyslipidemia. Multivariable linear regression was used to analyze the association between vitamin D levels and lipid profile markers. Odds ratios were calculated to assess the risk of atherogenic dyslipidemia in individuals with serum 25(OH)D levels below 30 ng/mL compared to those with levels above 30 ng/mL. Structural equation modeling (SEM) was employed to explore potential mediation pathways.

RESULTS

The study found a significant association between vitamin D levels and lower levels of LDL-C, LDL-TG, sdLDL-C, non-high-density lipoprotein cholesterol (non-HDL-C), triglycerides, and total cholesterol. Individuals with serum 25(OH)D levels below 30 ng/mL exhibited significantly higher odds ratios for developing atherogenic dyslipidemia in a dose-response pattern compared to those with vitamin D levels above 30 ng/mL. Notably, structural equation modeling (SEM) analysis revealed that vitamin D did not affect atherogenic lipid markers through the mediation of insulin resistance markers or high-sensitivity C-reactive protein.

CONCLUSION

This study provides evidence of an association between vitamin D deficiency and atherogenic dyslipidemia in young adults. It further highlights that individuals with serum 25(OH)D levels below 30 ng/mL are at a significantly higher risk of developing atherogenic dyslipidemia in a dose-response manner compared to those with higher vitamin D levels. These findings underscore the potential role of vitamin D in dyslipidemia management and emphasize the importance of maintaining sufficient vitamin D levels for cardiovascular health in young adults.

Alterations in regulators of the renal-bone axis, inflammation and iron status in older people with early renal impairment and the effect of vitamin D supplementation

CONTEXT

Chronic kidney disease (CKD) leads to alterations in fibroblast growth factor 23 (FGF23) and the renal-bone axis. This may be partly driven by altered inflammation and iron status. Vitamin D supplementation may reduce inflammation.

OBJECTIVE AND METHODS

Older adults with early CKD (estimated glomerular filtration rate (eGFR) 30-60 ml/min/1.73 m2; CKDG3a/b; n = 35) or normal renal function (eGFR >90 ml/min/1.73 m2; CKDG1; n = 35) received 12,000, 24,000 or 48,000 IU D3/month for 1 year. Markers of the renal-bone axis, inflammation and iron status were investigated pre- and post-supplementation. Predictors of c-terminal and intact FGF23 (cFGF23; iFGF23) were identified by univariate and multivariate regression.

RESULTS

Pre-supplementation, comparing CKDG3a/b to CKDG1, plasma cFGF23, iFGF23, PTH, sclerostin and TNFα were significantly higher and Klotho, 1,25-dihydroxyvitamin D and iron were lower. Post-supplementation, only cFGF23, 25(OH)D and IL6 differed between groups. The response to supplementation differed between eGFR groups. Only in the CKDG1 group, phosphate decreased, cFGF23, iFGF23 and procollagen type I N-propeptide increased. In the CKDG3a/b group, TNFα significantly decreased, and iron increased. Plasma 25(OH)D and IL10 increased, and carboxy-terminal collagen crosslinks decreased in both groups. In univariate models cFGF23 and iFGF23 were predicted by eGFR and regulators of calcium and phosphate metabolism at both time points; IL6 predicted cFGF23 (post-supplementation) and iFGF23 (pre-supplementation) in univariate models. Hepcidin predicted post-supplementation cFGF23 in multivariate models with eGFR.

CONCLUSION

Alterations in regulators of the renal-bone axis, inflammation and iron status were found in early CKD. The response to vitamin D3 supplementation differed between eGFR groups. Plasma IL6 predicted both cFGF23 and iFGF23 and hepcidin predicted cFGF23.

Non-linear Mendelian randomization: detection of biases using negative controls with a focus on BMI, Vitamin D and LDL cholesterol

Mendelian randomisation (MR) is an established technique in epidemiological investigation, using the principle of random allocation of genetic variants at conception to estimate the causal linear effect of an exposure on an outcome. Extensions to this technique include non-linear approaches that allow for differential effects of the exposure on the outcome depending on the level of the exposure. A widely used non-linear method is the residual approach, which estimates the causal effect within different strata of the non-genetically predicted exposure (i.e. the "residual" exposure). These "local" causal estimates are then used to make inferences about non-linear effects. Recent work has identified that this method can lead to estimates that are seriously biased, and a new method-the doubly-ranked method-has been introduced as a possibly more robust approach. In this paper, we perform negative control outcome analyses in the MR context. These are analyses with outcomes onto which the exposure should have no predicted causal effect. Using both methods we find clearly biased estimates in certain situations. We additionally examined a situation for which there are robust randomised controlled trial estimates of effects-that of low-density lipoprotein cholesterol (LDL-C) reduction onto myocardial infarction, where randomised trials have provided strong evidence of the shape of the relationship. The doubly-ranked method did not identify the same shape as the trial data, and for LDL-C and other lipids they generated some highly implausible findings. Therefore, we suggest there should be extensive simulation and empirical methodological examination of performance of both methods for NLMR under different conditions before further use of these methods. In the interim, use of NLMR methods needs justification, and a number of sanity checks (such as analysis of negative and positive control outcomes, sensitivity analyses excluding removal of strata at the extremes of the distribution, examination of biological plausibility and triangulation of results) should be performed.

Low-grade inflammation from prenatal period to age 6-8 years in a Vitamin D trial

BACKGROUND

Low-grade systemic inflammation measured as high sensitivity C-reactive protein (hs-CRP) has been associated with non-communicable disease risk. We assessed whether prenatal inflammation and early-childhood vitamin D are associated with inflammation until age 6-8.

METHODS

We analyzed blood hs-CRP and 25-hydroxy vitamin D [25(OH)D] in pregnancy, at birth from umbilical cord blood (UCB), from offspring at ages 1, 2, and 6-8 years in the Vitamin D Intervention in Infants (VIDI) study. VIDI was a randomized-controlled trial of vitamin D supplementation of 10 μg/day or 30 μg/day from age 2 weeks until 2 years in 975 infants recruited in 2013-14, with follow-up at age 6-8 in 2019-21 (n = 283).

RESULTS

Pregnancy hs-CRP was associated with UCB hs-CRP (r = 0.18, p < 0.001) but not independently with childhood hs-CRP (Estimate [95% CI] 0.04 [<-0.00, 0.09]). Higher UCB hs-CRP was associated independently with higher hs-CRP until 6-8 years (0.20 [0.12, 0.29]). Infant vitamin D dose had no effect on longitudinal hs-CRP (6-8 years, 0.11 [-0.04, 0.25]). Childhood 25(OH)D were associated positively with hs-CRP until age 6-8 (0.01 [>0.00, 0.01]).

CONCLUSION

Our results indicate that in children, inflammation, assessed by hs-CRP, persists from birth until 6-8 years. We observed positive associations between 25(OH)D and hs-CRP in vitamin D-sufficient children.

IMPACT

High sensitivity C-reactive protein (hs-CRP) concentrations tract from birth to age 8 years Our novel finding suggests a long-lasting pro-inflammatory phenotype in the child Higher vitamin D concentration - but not dose - is associated with higher childhood hs-CRP Chronic disease risk related to inflammation may in part originate from the prenatal period or early childhood Further studies are needed to investigate the effects of inflammation on long-term clinical health outcomes.

Accidental vitamin D3 overdose in a young man

Vitamin D3 (VD3) is a fat-soluble vitamin that can accumulate in the body and lead to toxicity by increasing 25(OH) D levels when consumed in large amounts. Maintaining 25(OH) D levels greater than 30 ng/mL is crucial for overall health due to the significant role of vitamin D in the body. The most common causes of VD3 intoxication are manufacturing errors or self-administration. Currently, there is no definitive data on the dose and duration of VD3 consumption that leads to toxicity. The maximum daily doses of VD3 that can be tolerated without causing adverse effects are not established. The maximum recommended amount for long-term supplementation is 2,000 units per day. Vitamin D3 toxicity (VDT) can present in various scenarios, ranging from asymptomatic to gastrointestinal, and in severe cases with neuropsychiatric and life-threatening symptoms. We report the case of a 29-year-old man who presented with symptoms of VDT following an accidental overdose of VD3 over 2 weeks.

Alzheimer's Disease: A Review of Pathology, Current Treatments, and the Potential Therapeutic Effect of Decreasing Oxidative Stress by Combined Vitamin D and l-Cysteine Supplementation

Significance: Excess oxidative stress and neuroinflammation are risk factors in the onset and progression of Alzheimer's disease (AD) and its association with amyloid-β plaque accumulation. Oxidative stress impairs acetylcholine (ACH) and N-methyl-d-aspartate receptor signaling in brain areas that function in memory and learning. Glutathione (GSH) antioxidant depletion positively correlates with the cognitive decline in AD subjects. Treatments that upregulate GSH and ACH levels, which simultaneously decrease oxidative stress and inflammation, may be beneficial for AD. Recent Advances: Some clinical trials have shown a benefit of monotherapy with vitamin D (VD), whose deficiency is linked to AD or with l-cysteine (LC), a precursor of GSH biosynthesis, in reducing mild cognitive impairment. Animal studies have shown a simultaneous decrease in ACH esterase (AChE) and increase in GSH; combined supplementation with VD and LC results in a greater decrease in oxidative stress and inflammation, and increase in GSH levels compared with monotherapy with VD or LC. Therefore, cosupplementation with VD and LC has the potential of increasing GSH, downregulation of oxidative stress, and decreased inflammation and AChE levels. Future Directions: Clinical trials are needed to determine whether safe low-cost dietary supplements, using combined VD+LC, have the potential to alleviate elevated AChE, oxidative stress, and inflammation levels, thereby halting the onset of AD. Goal of Review: The goal of this review is to highlight the pathological hallmarks and current Food and Drug Administration-approved treatments for AD, and discuss the potential therapeutic effect that cosupplementation with VD+LC could manifest by increasing GSH levels in patients. Antioxid. Redox Signal. 40, 663-678.

No evidence of a causal relationship between miscarriage and 25-hydroxyvitamin D: a Mendelian randomization study

STUDY QUESTION

Is there a causal relationship between 25-hydroxyvitamin D (25OHD) and miscarriage?

SUMMARY ANSWER

In this study, little evidence of a causal relationship was found between low serum 25OHD concentration or vitamin D deficiency and the risk of miscarriages.

WHAT IS KNOWN ALREADY

Associations between low vitamin D levels and increased risk of miscarriage have been reported, but causality is unclear.

STUDY DESIGN SIZE DURATION

The latest and largest genome-wide association studies (GWAS) for serum 25OHD concentration (n = 417 580), vitamin D deficiency (426 cases and 354 812 controls), miscarriage (16 906 cases and 149 622 controls), and the number of miscarriages (n = 78 700) were used to explore the causal association between serum vitamin D levels and miscarriage by two-sample Mendelian randomization analysis.

PARTICIPANTS/MATERIALS SETTING METHODS

This study was based on summary GWAS results from the FinnGen database and the UK Biobank. The random-effect inverse-variance weighted method was regarded as the primary analysis; MR-Egger, weighted median, weighted mode, simple mode, and MR-pleiotropy residual sum and outlier (MR-PRESSO) were further employed as complementary methods. MR-Egger intercept analysis and MR-PRESSO were employed to test pleiotropy, and Cochran's Q statistic and leave-one-out sensitivity analysis were used to determine the heterogeneity and robustness of the overall estimates, respectively.

MAIN RESULTS AND THE ROLE OF CHANCE

There was insufficient evidence of causal associations between serum 25OHD concentration and miscarriage (odds ratio (OR) = 0.995, 95% CI: 0.888 to 1.114, P = 0.927), or the number of miscarriages (β = -0.004, 95% CI: -0.040 to 0.032, P = 0.829). Furthermore, little evidence of causality between genetically determined vitamin D deficiency to miscarriage (OR = 0.993, 95% CI: 0.966 to 1.021, P = 0.624), or the number of miscarriages (β = 0.001, 95% CI: -0.009 to 0.011, P = 0.828), was observed. The results of the sensitivity analysis were robust, and no significant heterogeneity or horizontal pleiotropy was found.

LIMITATIONS REASONS FOR CAUTION

This study is limited by the absence of female-specific GWAS data and the limited amount of GWAS data available for this study, as well as the need for caution in generalizing the findings to non-European ethnic groups.

WIDER IMPLICATIONS OF THE FINDINGS

These findings enhance the current understanding of the intricate association between vitamin D and pregnancy outcomes, challenging prevailing beliefs regarding the strong association with miscarriage. The results provide a special perspective that may prompt further exploration and potentially offer insights for guiding future research and informing clinical guidelines pertaining to the management of miscarriage.

STUDY FUNDING/COMPETING INTERESTS

This project was supported by the Hubei Provincial Natural Science Foundation Program General Surface Project (2022CFB200), the Key Research & Developmental Program of of Hubei Province (2022BCA042), the Fundamental Research Funds for the Central Universities (2042022gf0007, 2042022kf1210), and the Interdisciplinary Innovative Talents Foundation from Renmin Hospital of Wuhan University (JCRCWL-2022-001, JCRCYG-2022-009). All authors have no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Bone Formation and Maintenance in Oral Surgery: The Decisive Role of the Immune System-A Narrative Review of Mechanisms and Solutions

Based on the evidence of a significant communication and connection pathway between the bone and immune systems, a new science has emerged: osteoimmunology. Indeed, the immune system has a considerable impact on bone health and diseases, as well as on bone formation during grafts and its stability over time. Chronic inflammation induces the excessive production of oxidants. An imbalance between the levels of oxidants and antioxidants is called oxidative stress. This physio-pathological state causes both molecular and cellular damage, which leads to DNA alterations, genetic mutations and cell apoptosis, and thus, impaired immunity followed by delayed or compromised wound healing. Oxidative stress levels experienced by the body affect bone regeneration and maintenance around teeth and dental implants. As the immune system and bone remodeling are interconnected, bone loss is a consequence of immune dysregulation. Therefore, oral tissue deficiencies such as periodontitis and peri-implantitis should be regarded as immune diseases. Bone management strategies should include both biological and surgical solutions. These protocols tend to improve immunity through antioxidant production to enhance bone formation and prevent bone loss. This narrative review aims to highlight the relationship between inflammation, oxidation, immunity and bone health in the oral cavity. It intends to help clinicians to detect high-risk situations in oral surgery and to propose biological and clinical solutions that will enhance patients' immune responses and surgical treatment outcomes.

Higher Vitamin D Levels before Methotrexate Therapy Initiation Are Associated with Lower Subsequent Mortality in Patients with Rheumatoid Arthritis

(1) Vitamin D deficiency is associated with mortality in the general population and has been observed in one rheumatoid arthritis (RA) cohort. Here, we investigate the relationship between 25-hydroxyvitamin D (25(OH)D) levels before methotrexate (MTX) therapy initiation in patients with RA and the subsequent all-cause mortality in a national Veterans Affairs (VA) cohort. (2) This is a retrospective study on RA patients time-oriented around the initial MTX prescription and 25(OH)D levels before starting MTX. We examined survival in patients with 25(OH)D levels > 50 nmol/L and ≤50 nmol/L using the Cox Proportional Hazard Model and fully adjusted for risk factors. (3) In total, 15,109 RA patients were included in the nationwide cohort. RA patients with 25(OH)D levels > 50 nmol/L before starting MTX had a 28% reduced risk of mortality when compared to those with levels ≤ 50 nmol/L (HR: 0.72, CI: 0.64-0.80, p < 0.001) after adjusting for traditional risk factors. (4) In this national RA cohort receiving standard-of-care MTX, patients with 25(OH)D levels > 50 nmol/L have a lower subsequent mortality when compared to those with 25(OH)D levels ≤ 50 nmol/L. It remains to be determined whether increasing Vitamin D levels in RA patients initially found to be Vitamin D deficient impacts their all-cause mortality.

Levels of Cell-Free DNA in Kidney Failure Patients before and after Renal Transplantation

Circulating cell-free DNA (cfDNA) has diverse applications in oncological, prenatal, toxicological, cardiovascular, and autoimmune diseases, diagnostics, and organ transplantation. In particular, mitochondrial cfDNA (mt-cfDNA) is associated with inflammation and linked to early vascular ageing (EVA) in end-stage kidney failure (ESKF), which could be a noninvasive marker for graft rejection and organ damage. Plasma samples from 44 ESKF patients, of whom half (n = 22) underwent either conservative therapy (non-HD) or hemodialysis (HD) before kidney transplantation (KT). These samples were analyzed at baseline and two years after KT. cfDNA was extracted from plasma and quantified using the fluorometric method. qPCR was used to quantify and differentiate the fractions of mt-cfDNA and nuclear cfDNA (nc-cfDNA). mt-cfDNA levels in KT patients decreased significantly from baseline to two years post-KT (p < 0.0268), while levels of total cfDNA and nc-cfDNA did not differ. Depending on therapy modality (HD vs. non-HD) before KT, total cfDNA levels were higher in HD patients at both baseline (p = 0.0133) and two years post-KT (p = 0.0421), while nc-cfDNA levels were higher in HD only at baseline (p = 0.0079). Males showed a nonsignificant trend of higher cfDNA levels. Patients with assessed vascular fibrosis (p = 0.0068), either alone or in combination with calcification plus fibrosis, showed reduced mt-cfDNA post-KT (p = 0.0195). Changes in mt-cfDNA levels suggests the impact of KT on the inflammatory state of ESKF, as evidenced via its correlation with high sensitivity C-reactive protein after KT. Further studies are warranted to assess if cfDNA could serve as a noninvasive method for monitoring the response to organ transplantation and even for amelioration of EVA status per se.

Organic Synthesis of New Secosteroids from Fucosterol, Its Intestinal Absorption by Caco-2 Cells, and Simulation of the Biological Activities of Vitamin D

We previously examined the cellular uptake of six types of vitamin D in human intestinal Caco-2 cells. Since vitamins D5-D7 were commercially unavailable, we synthesized these compounds organically before studying them. This process led us to understand that new secosteroids could be generated as vitamin D candidates, depending on the sterol used as the starting material. We obtained two new secosteroids-compounds 3 and 4-from fucosterol in the current study. We investigated the intestinal absorption of these compounds using Caco-2 cells cultured in Transwells and compared the results with vitamin D3, a representative secosteroid. The intestinal absorption of compound 4 was comparable to that of vitamin D3. Compound 3 showed similar uptake levels but transported about half as much as vitamin D3. These compounds demonstrated intestinal absorption at the cellular level. Vitamin D is known for its diverse biological activities manifest after intestinal absorption. Using PASS online simulation, we estimated the biological activity of compound 3's activated form. In several items indicated by PASS, compound 3 exhibited stronger biological activity than vitamins D2-D7 and was also predicted to have unique biological activities.

Calcium Homeostasis and Psychiatric Disorders: A Mendelian Randomization Study

Observational studies have investigated the impact of calcium homeostasis on psychiatric disorders; however, the causality of associations is yet to be established. Bidirectional Mendelian randomization (MR) analysis of calcium homeostasis hormones was conducted on nine psychiatric disorders. Calcium, serum 25-hydroxyvitamin D levels (25OHD), parathyroid hormone, and fibroblast growth factor 23 are the major calcium homeostasis hormones. The causality was evaluated by the inverse variance weighted method (IVW) and the MR Steiger test, while Cochran's Q test, the MR-Egger intercept test, funnel plot, and the leave-one-out method were used for sensitivity analyses. Bonferroni correction was used to determine the causative association features (p < 6.94 × 10-4). Schizophrenia (SCZ) was significantly associated with decreased 25OHD concentrations with an estimated effect of -0.0164 (Prandom-effect IVW = 2.39 × 10-7). In the Multivariable MR (MVMR) analysis adjusting for potentially confounding traits including body mass index, obesity, mineral supplements (calcium, fish oil, and vitamin D) and outdoor time (winter and summer), the relationship between SCZ and 25OHD remained. The genetically predicted autism spectrum disorder and bipolar disorder were also nominally associated with decreased 25OHD. This study provided evidence for a causal effect of psychiatric disorders on calcium homeostasis. The clinical monitoring of 25OHD levels in patients with psychiatric disorders is beneficial.

Causal relationships between circulating inflammatory factors and IgA vasculitis: a bidirectional Mendelian randomization study

Background

IgA vasculitis (IgAV) is an immune-associated vasculitis, yet its exact etiology remains unclear. Here, we explore the interaction between IgAV and inflammatory factors using bidirectional Mendelian randomization (MR).

Methods

We conducted a bidirectional summary-level MR analysis to delineate the causality of C-reactive protein (CRP), procalcitonin (PCT), and 41 circulating inflammatory regulators with IgAV. Data on genetic variants related to inflammation were obtained from three genome-wide association studies (GWASs) on CRP, PCT, and human cytokines, whereas data on IgAV was from large meta-analyses of GWAS among 216 569 FinnGen Biobank participants. The primary MR analysis was performed using the inverse-variance weighted (IVW) approach, and the sensitivity analyses were carried out using MR-Egger, weighted median, weighted mode, and MR-pleiotropy residual sum and outlier.

Results

This study revealed the association of CRP higher levels with increased risk of IgAV through IVW method (Estimate odds ratio [OR] = 1.41, 95% confidence interval [CI]: 1.01-1.98, P = 0.04), MR-Egger (OR = 1.87, CI: 1.15-3.02, P = 0.01), weighted median (OR = 2.00, CI: 1.21-3.30, P = 0.01) and weighted mode (OR = 1.74, CI: 1.13-2.68, P = 0.02). Furthermore, elevated IL-8 was strongly implicated with a higher risk of IgAV (IVW OR = 1.42, CI: 1.05-1.92; P = 0.02). Conversely, genetically predicted IgAV was associated with decreased levels of TNF-β (IVW estimate β = -0.093, CI: -0.178 - -0.007; P = 0.033). Additionally, no such significant statistical differences for other inflammatory factors were found.

Conclusion

Our current study using bidirectional MR analysis provides compelling evidence for a causal effect of CRP, PCT, and circulating inflammatory regulators on IgAV. These findings contribute to a better understanding of the pathogenesis of IgAV and emphasize the potential of targeting inflammatory factors for therapeutic interventions.

About the associations of vitamin D deficiency and biomarkers of systemic inflammatory response with all-cause and cause-specific mortality in a general population sample of almost 400,000 UK Biobank participants

It is unknown whether the well-known association between vitamin D deficiency and mortality could be explained by the immune system modulating effects of vitamin D, which may protect from a systemic inflammatory response (SIR) to adverse health conditions. This study aims to investigate the interrelationships of vitamin D deficiency, biomarkers of SIR, and mortality. We used multivariate logistic regression with adjustment for 51 covariates to assess the associations of vitamin D deficiency with disadvantageous levels of nine biomarkers of SIR in the UK Biobank cohort. Furthermore, we tested with Cox regression and mediation analysis whether biomarkers of SIR and vitamin D deficiency were independently associated with mortality. We included 397,737 participants aged 37-73 years. Vitamin D deficiency was associated with disadvantageous levels of all blood cell count-based biomarkers, but not with C-reactive protein (CRP)-based biomarkers after adjustment for body weight. Vitamin D deficiency and all biomarkers of SIR were significantly associated with all-cause mortality and mortality from cancer, cardiovascular and respiratory disease. The strength of these associations was unaltered if vitamin D deficiency and biomarkers of SIR were put in the same model. This finding was further supported by the mediation analyses. This study showed that vitamin D deficiency is associated with disadvantageous levels of blood cell count-based but not CRP-based biomarkers of SIR. Vitamin D deficiency and systemic inflammation were independently and strongly associated with mortality. The potential of clinical interventions against both vitamin D deficiency and underlying causes of systemic inflammation should be explored.

Serum levels of vitamin D and periodontal inflammation in community-dwelling older Japanese adults: The Otassha Study

AIM

To evaluate the association between vitamin D status and periodontal inflammation as determined by the periodontal inflamed surface area (PISA) in community-dwelling older adults.

MATERIALS AND METHODS

This cross-sectional study included 467 Japanese adults (mean age = 73.1 years) who underwent full-mouth periodontal examinations and measurements of serum levels of 25-hydroxyvitamin D (25(OH)D). We used linear regression and restricted cubic spline models to analyse the association between exposure (serum 25(OH)D) and outcome (PISA).

RESULTS

The linear regression model showed that, after adjusting for potential confounders, participants in the lowest quartile of serum 25(OH)D had 41.0 mm2 more PISA (95% confidence interval [CI]: 4.6-77.5) than the reference group (the highest quartile of serum 25(OH)D). The spline model showed that the association between serum 25(OH)D and PISA was non-linear and restricted to the low 25(OH)D range. PISA initially sharply decreased as serum 25(OH)D increased, and then the decreasing trend slowed and plateaued. The inflection point with the minimum PISA value was a serum 25(OH)D level of 27.1 ng/mL, above which there was no decreasing trend in PISA with increasing serum 25(OH)D levels.

CONCLUSIONS

Low vitamin D status had an L-shaped association with periodontal inflammation in this cohort of Japanese adults.

Methotrexate Chemotherapy Causes Growth Impairments, Vitamin D Deficiency, Bone Loss, and Altered Intestinal Metabolism-Effects of Calcitriol Supplementation

Vitamin D deficiency or insufficiency is prevalent in childhood cancer patients and survivors after chemotherapy; further studies are needed to investigate the underlying aetiology and effectiveness of vitamin D supplementation in preventing chemotherapy-induced bone loss. This study used a rat model of treatment with antimetabolite methotrexate to investigate whether methotrexate chemotherapy causes vitamin D deficiency and if vitamin D supplementation attenuates the resultant bone loss. Methotrexate treatment (five daily injections) decreased serum vitamin D levels (from 52 to <30 ng/mL), reduced body and bone lengthening and tibial trabecular bone volume, and altered intestinal vitamin D metabolism, which was associated with intestinal mucosal damage known to cause malabsorption of nutrients, including dietary vitamin D and calcium. During the early stage after chemotherapy, mRNA expression increased for vitamin D activation enzyme CYP27B1 and for calcium-binding protein TRPV6 in the intestine. During the intestinal healing stage, expression of vitamin D catabolism enzyme CYP24 increased, and that of TRPV6 was normalised. Furthermore, subcutaneous calcitriol supplementation diminished methotrexate-induced bone loss due to its effect suppressing methotrexate-induced increased bone resorption. Thus, in young rats, methotrexate chemotherapy causes vitamin D deficiency, growth impairments, bone loss, and altered intestinal vitamin D metabolism, which are associated with intestinal damage, and vitamin D supplementation inhibits methotrexate-induced bone loss.

Maternal vitamin D deficiency in early pregnancy and perinatal and long-term outcomes

Background

Vitamin D deficiency is common in pregnant women. Some studies have linked vitamin D deficiency to obstetric complications such as gestational hypertension, gestational diabetes, and preterm birth. Therefore, the objective of this study is to investigate the potential impact of vitamin D deficiency during pregnancy on both perinatal and long-term outcomes.

Methods

In this retrospective study, conducted between 2017 and 2021, we analyzed the data of 1079 singleton pregnant women with no medical or surgical complications prior to pregnancy. We evaluated obstetric and perinatal outcomes, as well as neurodevelopmental outcomes using Bayley-III tests, Gross Motor Function Measure, or chart review.

Results

The maternal serum vitamin D level in the first trimester was 18.2 ± 9.0 ng/mL. Vitamin D deficiency (<20 ng/mL) was found in 308 (62.0%) women in the first trimester, of which 288 women (26.7%) were in the very deficient group (<10 ng/mL). There were no differences in maternal age, body mass index, and previous preterm birth between the group with vitamin D < 10 ng/mL and ≥10 ng/mL group. There were also no differences in the rates of gestational hypertension, gestational diabetes, and preterm birth between the two groups, except for the rate of preterm birth before 37 weeks of gestation, which was significantly higher in the very deficient group (adjusted odds ratios [aOR] = 7.78, 95%CI [2.23-27.12], p = 0.001). In the very deficient group, the risk of developmental delay was also higher (aOR = 4.28, 95%CI [1.40-13.05], p = 0.011).

Conclusions

This is the first study to analyze the effects of maternal vitamin D deficiency during pregnancy on both long-term developmental outcomes and perinatal prognosis. Vitamin D deficiency, defined as a level lower than 10 ng/mL in the first trimester, may increase the risk of preterm birth and developmental delay in children.

Association between serum 25-hydroxyvitamin D concentrations and hypertension among adults in North Sudan: a community-based cross-sectional study

BACKGROUND

Globally, hypertension represents a major public health problem. The association between 25-hydroxyvitamin D (25[OH]D) levels and hypertension remains unclear. The current study aimed to investigate the association between serum 25(OH)D levels and hypertension among adults in Sudan.

METHODS

A community-based cross-sectional study was conducted among adults in North Sudan. Sociodemographic and clinical data were collected using a questionnaire and face-to-face interviews. Serum 25(OH)D was measured using an enzyme-linked immunosorbent assay. Multivariate logistic regression and multiple linear regression analyses were performed.

RESULTS

Of the total of 391 participants, 202 (51.7%) were females. The median (interquartile range [IQR]) of participants' ages was 45(32-55) years. Of the total, 219(56.0%) had hypertension. The median (IQR) of serum25(OH)D was 13.3(9.9-19.7) ng/mL, and 295 (75.4%) participants had vitamin D deficiency (< 20 ng/mL). In multivariable logistic regression, the adjusted odds ratio (AOR) for age = 1.05, 95% confidence interval (CI)1.03‒1.061, the AOR for being female = 2.02, 95% CI, 1.12‒3.66, and body mass index was AOR = 1.09, 95% CI, 1.05‒1.14, all of which were significantly associated with hypertension. However, serum 25(OH)D levels were not associated with hypertension (AOR = 1.01, 95% CI 0.99‒1.05, P = 0.317). In multiple linear regression, while systolic blood pressure was negatively associated with 25(OH)D (coefficient = - 0.28, P = 0.017), there was no significant association between serum 25(OH)D level and diastolic blood pressure (coefficient = - 0.10, P = 0.272) or mean blood pressure (coefficient =-0.03, P = 0.686).

CONCLUSION

The current study revealed a negative association between vitamin D and systolic blood pressure. The mechanism of such an association needs further study.

Vitamin D and suicidality: a Chinese early adolescent cohort and Mendelian randomization study

AIMS

Previous cross-sectional and case-control studies have proposed that decreased vitamin D levels are positively correlated with the risk of suicidality in adults. However, limited studies have examined the association between vitamin D and suicidality in adolescents. This study aimed to investigate the relationship between serum vitamin D and suicidality risk among early adolescents.

METHODS

Data were obtained from a Chinese early adolescent cohort. In this cohort, seventh-grade students from a middle school in Anhui Province were invited to voluntarily participate in the baseline assessments and provide peripheral blood samples (in September 2019). The participants were followed up annually (in September 2020 and September 2021). Serum 25-hydroxyvitamin D [25(OH)D] and vitamin D-related single-nucleotide polymorphisms at baseline were measured in November 2021. Traditional observational and Mendelian randomization (MR) analyses were performed to examine the relationship between serum 25(OH)D at baseline and the risk of baseline and incident suicidality (i.e., suicidal ideation [SI], plans and attempts).

RESULTS

Traditional observational analysis did not reveal a significant linear or non-linear association of serum 25(OH)D concentration with the risks of baseline and 2-year incident suicidality in the total sample (P > .05 for all). Sex-stratified analysis revealed a non-linear association between the 25(OH)D concentration and the risk of baseline SI in women (Poverall = .002; Pnon-linear = .001). Moreover, the risk of baseline SI in the 25(OH) insufficiency group was lower than that in the 25(OH) deficiency group in the total sample (odds ratio [OR] = 0.69, 95% confidence interval [CI] = 0.51-0.92, P = .012). This difference remained significant in women (OR = 0.59, 95% CI = 0.40-0.87, P = .008) but not in men (OR = 0.78, 95% CI = 0.53-1.15, P = .205). Additionally, both linear and non-linear MR analyses did not support the causal effect of serum 25(OH)D concentration on the risk of baseline, 1-year and 2-year incident suicidality (P > .05 for all).

CONCLUSIONS

This study could not confirm the causal effect of vitamin D on suicidality risk among Chinese early adolescents. Future studies must confirm these findings with a large sample size.