Sex differences in vitamin D metabolism, serum levels and action

Vitamin D Status and Cardiovascular Risk Factors in Patients with Type 2 Diabetes Mellitus: A Cross-Sectional Study in a Tertiary-Level Hospital in Antananarivo, Madagascar

Background

Diabetes mellitus is already a major cardiovascular risk factor (CRF). Hypovitaminosis D is common in patients with type 2 diabetes mellitus (T2DM). It also increases the cardiovascular risk of these subjects.

Objective

To determine the vitamin D status of Malagasy with T2DM seen at the Soavinandriana Hospital Center, and the association between hypovitaminosis D and CRF.

Methods

This was a cross-sectional study, carried out over a period of 2 years. Assayed by the chemiluminescence technique, vitamin D was "normal", "insufficient" and "deficient" if the 25-hydroxyvitamin D plasma was ≥30 ng/mL, 20-29 ng/mL and ≤19 ng/mL, respectively. Hypovitaminosis D was the set of vitamin D insufficiency and deficiency.

Results

Among the 318 T2DM, the prevalence of hypovitaminosis D was 66.0% (45.2% insufficiency and 20.8% deficiency). Their factors associated were age ≥70 years (OR = 2.15 [1.26-3.66]), glycated haemoglobin ≥7% (4.97 [2.97-8.39]), and retinopathy (OR = 4.15 [1.85-9.32]). After adjustment for age, Hb A1c ≥7% and retinopathy, hypovitaminosis D was associated with hypertension (OR = 8.77 [4.76-16.2]), dyslipidaemia (OR = 8.05 [3.98-14.5]), ex-smoking (OR = 6.07 [2.78-13.3]), microalbuminuria (OR = 2.95 [1.25-6.97]) and carotid atherosclerosis (OR = 2.96 [1.83-4.35]).

Conclusion

Hypovitaminosis D was common in T2DM. Its treatment is primarily preventive. It is also important to control associated CRF, diabetes and its complications.

Prevalence and patterns of vitamin D deficiency and its role in cognitive functioning in a cohort from South India

Vitamin D (VitD) is a naturally occurring, fat-soluble vitamin which regulates calcium and phosphate homeostasis in the human body and is also known to have a neuroprotective role. VitD deficiency has often been associated with impaired cognition and a higher risk of dementia. In this study, we aimed to explore the relationship between levels of VitD and cognitive functioning in adult individuals. 982 cognitively healthy adults (≥ 45 years) were recruited as part of the CBR-Tata Longitudinal Study for Aging (TLSA). Addenbrooke's cognitive examination-III (ACE-III) and Hindi mental status examination (HMSE) were used to measure cognitive functioning. 25-hydroxyvitamin D [25(OH)D] levels were measured from the collected serum sample and classified into three groups- deficient (< 20 ng/ml), insufficient (20-29 ng/ml) and normal (≥ 30 ng/ml). Statistical analysis was done using IBM SPSS software, version 28.0.1.1(15). The mean age of the participants was 61.24 ± 9 years. Among 982 participants, 572 (58%) were deficient, 224 (23%) insufficient and only 186 (19%) had normal levels of VitD. Kruskal-Wallis H test revealed a significant difference in age (p = 0.015) and education (p = 0.021) across VitD levels and the Chi-square test revealed a significant association between gender (p = 0.001) and dyslipidemia status (p = 0.045) with VitD levels. After adjusting for age, education, gender and dyslipidemia status, GLM revealed that individuals with deficient (p = 0.038) levels of VitD had lower scores in ACE-III verbal fluency as compared to normal. Additionally, we also found that 91.2% individuals who had VitD deficiency were also having dyslipidemia. It is concerning that VitD deficiency impacts lipid metabolism. Lower levels of VitD also negatively impacts verbal fluency in adult individuals. Verbal fluency involves higher order cognitive functions and this result provides us with a scope to further investigate the different domains of cognition in relation to VitD deficiency and other associated disorders.

Effect of vitamin D supplementation or fortification on bone turnover markers in women: a systematic review and meta-analysis

Vitamin D is a vital indicator of musculoskeletal health, as it plays an important role through the regulation of bone and mineral metabolism. This meta-analysis was performed to investigate the effects of vitamin D supplementation/fortification on bone turnover markers in women. All human randomised clinical trials reported changes in bone resorption markers (serum C-terminal telopeptide of type-I collagen (sCTX) and urinary type I collagen cross-linked N-telopeptide (uNTX)) or bone formation factors (osteocalcin (OC), bone alkaline phosphatase (BALP) and procollagen type-1 intact N-terminal propeptide (P1NP)) following vitamin D administration in women (aged ≥ 18 years) were considered. Mean differences (MD) and their respective 95 % CI were calculated based on fixed or random effects models according to the heterogeneity status. Subgroup analyses, meta-regression models, sensitivity analysis, risk of bias, publication bias and the quality of the included studies were also evaluated. We found that vitamin D supplementation had considerable effect on sCTX (MD: -0·038, n 22) and OC (MD: -0·610, n 24) with high heterogeneity and uNTX (MD: -8·188, n 6) without heterogeneity. Our results showed that age, sample size, dose, duration, baseline vitamin D level, study region and quality of studies might be sources of heterogeneity in this meta-analysis. Subgroup analysis also revealed significant reductions in P1NP level in dose less than 600 μg/d and larger study sample size (>100 participants). Moreover, no significant change was found in BALP level. Vitamin D supplementation/fortification significantly reduced bone resorption markers in women. However, results were inconsistent for bone formation markers.

Seasonal and sex-related variation in vitamin D status and its association with other biochemical markers in young individuals: A cross-sectional study

BACKGROUND

While several studies have investigated the association between vitamin D deficiency and biochemical parameters, the results are still inconsistent and mostly overlook seasonal variations. This study explored the relationships between 25-hydroxy-vitamin D (25(OH)D) concentrations, biochemical markers, and seasonal variation among young males and females.

METHODS

A cross-sectional study was conducted among 203 individuals aged 18-24 years of both sexes residing in Brasilia, Brazil (latitude: 15°S). Sociodemographic variables, season of blood collection, and serum levels of 25(OH)D, total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, glycated hemoglobin (HbA1c), glucose, insulin, hs-CRP, parathyroid hormone, ionized calcium, and alkaline phosphatase were included. Descriptive statistics and differences among groups, correlations, and linear regression tests were performed.

RESULTS

The mean age of the participants was 21.17±1.7 years, and the mean serum 25(OH)D level was 25.76±7.0 ng/mL. Of the participants, 50.7% had vitamin D insufficiency (20 to 29.9 ng/mL), and 23.2% were vitamin D deficient (≤20 ng/mL). Vitamin D deficiency was higher in the spring (53.2%) and among females (29.5%). In young men with vitamin D insufficiency/deficiency (≤29.9 ng/mL) (n = 49), 25(OH)D levels were inversely correlated with HOMA-β (r = -0.234, p = 0.032) and triglyceride (r = -0.415, p = 0.003) levels. However, there were no significant correlations between 25(OH)D concentrations and biochemical markers among women with insufficient and deficient vitamin D levels.

CONCLUSION

This study found a high prevalence of vitamin D insufficiency/deficiency among young individuals living in Brasília, Brazil, particularly women and during the spring season. Our findings suggest that lower 25(OH)D levels (≤29.9 ng/mL) may be associated with insulin resistance and an increased risk of cardiovascular disease in young men studied. However, further studies with larger representative samples are needed to explore the mechanisms underlying the association between vitamin D and biochemical parameters.

Prevalence of vitamin D deficiency and its association with cardiometabolic risk factors among healthcare workers in the Eastern Cape province, South Africa; cross-sectional study

This study assesses the prevalence of Vitamin D deficiency and its potential association with cardiometabolic risk factors among South African adults residing in the Eastern Cape province. In this cross-sectional study, 1244 healthcare workers (HCWs) completed a self-administered questionnaire and venous blood samples were drawn at two academic hospitals in the Eastern Cape. History of hypertension and diabetes mellitus were self-reported. Participants were categorised as obese if their body mass index (BMI) ≥ 30 kg/m2. Participants were classified as having metabolic syndrome if they had hypertension, diabetes mellitus and obesity. Vitamin D [25(OH)D] deficiency was defined as venous blood concentrations < 50 nmol/L. Associations between vitamin D deficiency and participants' characteristics were assessed using multivariate logistic regression model analysis. The prevalence of vitamin D deficiency was 28.5% (n = 355), of whom 292 were female. Among the participants who were deficient in vitamin D, the prevalence of obesity, diabetes mellitus, hypertension, chronic kidney disease, and metabolic syndrome was 64.9% (n = 230), 9% (n = 32), 16.6% (n = 59), 2.3% (n = 8) and 18% (n = 64), respectively. In the adjusted multivariate logistic regression model, black Africans (AOR = 2.87; 95% CI 1.52-5.43) and individuals ≥ 42 years (AOR = 1.37; 95% CI 1.07-1.77) were more likely to exhibit vitamin D deficiency. However, there was no significant association by age, sex, and cardiometabolic markers. More than one in four healthcare workers was deficient in vitamin D among the study sample, especially the black Africans and older individuals. Further studies are needed at the population level to elucidate on the vitamin D status in the region.

Vitamin D metabolism is altered during aging alone or combined with obesity in male mice

Aging and obesity are associated with a decrease in plasma 25-hydroxyvitamin D (25(OH)D) levels. In the context of a growing aging population and the rising incidence of obesity, we hypothesized that aging process, either independently or in combination with obesity, could influence vitamin D (VD) metabolism, consequently resulting in the reduced 25(OH)D plasma concentrations. C57BL/6JRJ young (6 months) and old (23 months) mice fed with control (CD) or high fat diet (HF) were compared. Plasma and adipose concentration of cholecalciferol and 25(OH)D and mRNA expression of genes coding for the main VD actors were analyzed. Aging was associated with a decrease in plasma 25(OH)D levels, whereas combined effect of obesity and aging did not generate a cumulative effect on plasma 25(OH)D levels. The mRNA expression of Cyp27a1, Cyp3a11, and Cyp2j6 were decreased in the liver during aging. Together, these regulations could explain the reduced 25-hydroxylation. Interestingly, the lack of cumulative reduction of 25(OH)D in aged and obese mice could be related to the strong induction of Cyp2j6. In kidneys, a complex modulation of Cyp27b1 and Cyp24a1 could contribute to the reduced 25-hydroxylation in the liver. In white adipose tissue, an induction of Cyp2r1 was observed during aging and obesity, together with an increase of 25(OH)D quantity, suggesting an exacerbated storage that may participated to the reduced plasma 25(OH)D levels. These findings support the notion that aging alone or combined with obesity, induces regulation of VD metabolism in the organs, beyond the classical reduction of epidermal VD precursor, which may contribute to the decrease in 25(OH)D levels.

Vitamin D status in post-medieval Northern England: Insights from dental histology and enamel peptide analysis at Coach Lane, North Shields (AD 1711-1857)

OBJECTIVES

The post-medieval period in Europe saw a dramatic increase in metabolic bone disease related to vitamin D deficiency (VDD). Recent paleopathological work has utilized interglobular dentin (IGD) as a proxy for poor vitamin D status during development, while enamel peptide analysis allows the identification of chromosomal sex in non-adult remains. Here we explore the relationship between sex, the presence of IGD, and macroscopic markers of VDD in an industrial era assemblage from Northeast England.

MATERIALS AND METHODS

25 individuals (9 females, 9 males, 9 unknown sex) from the cemetery site at Coach Lane, North Shields (1711-1857) were selected for paleopathological analysis, histological assessment of IGD, and enamel peptide determination of chromosomal sex.

RESULTS

Ground tooth sections from 21 individuals were of suitable quality for detection of IGD, and enamel peptide analysis confirmed the chromosomal sex of ten individuals. Sixteen individuals (76.1%) exhibited ≥1 episode of IGD. Nine of these (42.8%) exhibited >1 episode and four (19%) exhibited ≥4 episodes in regular intervals. Male sex was significantly associated with the presence of IGD (p = 0.0351; 100% males vs. 54.5% females). Females were more likely to exhibit macroscopic evidence of VDD (45.5% females vs 30% males) but this was not statistically significant.

DISCUSSION AND CONCLUSIONS

Periods of poor mineral metabolism during childhood appear much more prevalent at Coach Lane than macroscopic evidence suggests. Evidence of seasonal IGD episodes indicates that northern latitude played a major role in poor VD status in the Northeast of England. The significant association of IGD with male sex may be due to sex-related differences in dentinal mineralization or a higher risk of poor VD status in males aged <5 years. More work is needed to establish an evidence-based threshold for pathological levels of IGD before the presence of this feature can confidently be used as a biomarker for poor VD status.

Oxidative stress-related genetic variation and antioxidant vitamin intake in intact and ruptured abdominal aortic aneurysm: a Swedish population-based retrospective cohort study

AIMS

The aim of this study is to investigate how genetic variations in genes related to oxidative stress, intake of antioxidant vitamins, and any potential interactions between these factors affect the incidence of intact abdominal aortic aneurysm (AAA) and its rupture (rAAA), accounting for sex differences where possible.

METHODS AND RESULTS

The present retrospective cohort study (n = 25 252) uses baseline single-nucleotide polymorphisms (SNPs) and total antioxidant vitamin intake data from the large population-based, Malmö Diet and Cancer Study. Cumulative incidence of intact AAA was 1.6% and of rAAA 0.3% after a median follow-up of 24.3 years. A variant in NOX3 (rs3749930) was associated with higher rAAA risk in males [adjusted hazard ratio (aHR): 2.49; 95% confidence interval (CI): 1.36-4.35] and the overall population (aHR: 1.88; 95% CI: 1.05-3.37). Higher intakes of antioxidant vitamins, riboflavin, and folate were associated with 20% and 19% reduced intact AAA incidence, respectively. Interestingly, the inverse associations between riboflavin and vitamin D intake with intact AAA incidence were stronger in the individuals carrying the NOX3 variant as compared with the wild-type recessive genotype, i.e. by 60% and 66%, respectively (P for interaction < 0.05). Higher riboflavin intake was associated with a 33% male-specific intact AAA risk reduction, while higher intake of vitamin B12 intake was associated with 55% female-specific intact AAA risk increase; both these associations were significantly modified by sex (P for interaction < 0.05).

CONCLUSIONS

Our findings highlight the role of oxidative stress genetic variations and antioxidant vitamin intake in AAA. Although a low AAA/rAAA sample size limited some analyses, especially in females, our findings highlight the need for future randomized controlled trials and mechanistic studies, to explore the potential benefits of antioxidant vitamins while accounting for genetic and sex differences.

Impact of COVID-19 Pandemic and Associated Restrictions on Vitamin D Status in a Large Cohort of Italian Children and Adolescents

Background and Objectives: Vitamin D is synthesized in the skin upon sunlight exposure, showing variations with season and latitude. We aimed to investigate the influence of age, sex, and season on vitamin D status in a large pediatric cohort during the COVID-19 pandemic period and the corresponding pre-pandemic period. Materials and Methods: Retrospective data concerning subjects aged < 18 years were extracted anonymously from the large database of a reference laboratory hospital (Sassari, Northern Sardinia, Italy). Serum 25-hydroxyvitamin D [25(OH)D] levels measured during the pre-pandemic period (1 March 2018 to 30 September 2019) were compared with those detected during the pandemic period (1 March 2020 to 30 September 2021). Results: A total of 2317 samples from subjects aged < 18 years were included in the analysis, 1303 (47.9% females) of which were collected in the pre-pandemic period and 1014 (51.3% females) in the pandemic period. No significant differences in 25(OH)D levels were found between the two periods, whereas, in children aged < 2 years, levels were higher than those in children aged 11-16 years (p < 0.05). Monthly levels of 25(OH)D between pre-pandemic and pandemic periods did not differ, although significant differences were detected across months (p < 0.0001). Similarly, 25(OH)D values did not differ significantly between males and females in both periods. Marked seasonal variations were observed in males and females across all age groups. Conclusions: Serum vitamin D levels and their season-related variations were not significantly affected by the COVID-19 pandemic and associated restrictions in a large cohort of Italian children and adolescents.

Changes in DNA Methylation and mRNA Expression in Lung Tissue after Long-Term Supplementation with an Increased Dose of Cholecalciferol

Maintaining an appropriate concentration of vitamin D is essential for the proper functioning of the body, regardless of age. Nowadays, there are more and more indications that vitamin D supplementation at higher than standard doses may show protective and therapeutic effects. Our study identified differences in the body's response to long-term supplementation with cholecalciferol at an increased dose. Two groups of pigs were used in the experiment. The first group received a standard dose of cholecalciferol (grower, 2000 IU/kg feed, and finisher, 1500 IU/kg feed), and the second group received an increased dose (grower, 3000 IU/kg feed, and finisher, 2500 IU/kg feed). After slaughter, lung samples were collected and used for RRBS and mRNA sequencing. Analysis of the methylation results showed that 2349 CpG sites had significantly altered methylation patterns and 1116 (47.51%) identified DMSs (Differentially Methylated Sites) were related to genes and their regulatory sites. The mRNA sequencing results showed a significant change in the expression of 195 genes. The integrated analysis identified eleven genes with DNA methylation and mRNA expression differences between the analyzed groups. The results of this study suggested that an increased vitamin D intake may be helpful for the prevention of lung cancer and pulmonary fibrosis. These actions may stem from the influence of vitamin D on the expression of genes associated with collagen production, such as SHMT1, UGT1A6, and ITIH2.The anti-cancer properties of vitamin D are also supported by changes in KLHL3 and TTPA gene expression.

Nutritional strategies to optimise musculoskeletal health for fall and fracture prevention: Looking beyond calcium, vitamin D and protein

Falls and osteoporotic fractures are a major public health problem, particularly among older adults. A third of individuals aged 65 years and over fall at least once each year, with up to 20 % of these resulting in serious injury, including fracture. In conjunction with regular exercise, the importance of diet for musculoskeletal health has largely focused upon calcium, vitamin D, and protein, particularly in the context of preventing falls and fractures. Whilst there is evidence for the benefits of these nutrients for musculoskeletal health, other aspects of the diet remain largely underexplored. For example, vegetables are rich sources of macro- and micronutrients that are essential for muscle function and bone health, which are key factors in the prevention of falls and fractures. Recent work has highlighted the importance of nutrients such as vegetable-derived nitrate and vitamin K1 in optimising muscle strength, physical function, and bone quality. In the context of dietary patterns, vegan/plant-based diets have recently gained popularity due to perceived health benefits, animal welfare, or to tackle climate change. The elimination and/or substitution of animal-based products for plant foods (without careful planning and/or expert dietary guidance) could, however, have long-term negative musculoskeletal consequences; a trend uncovered by recent evidence. Within the overarching theme of nutrition for fall and fracture prevention in older populations, the aim of this review is to (i) summarise the current evidence for calcium, vitamin D and protein; (ii) describe the importance of vegetables and selected nutrients, such as nitrate and vitamin K1, for muscle function and bone structural integrity; and (iii) highlight current evidence around different dietary patterns (e.g., plant-based, diet quality, data driven approaches) and their impact on musculoskeletal health.

Incidence of vitamin D deficiency in adolescent idiopathic scoliosis: a meta-analysis

Introduction

This study aimed to investigate the incidence of vitamin D deficiency in patients with adolescent idiopathic scoliosis through a meta-analysis and to analyze trends and risk factors.

Methods

Potentially relevant studies were searched using the terms "Vitamin D AND scoliosis." Data on the incidence and risk factors, such as race, curve magnitude, and sex, were extracted from the selected studies. Review Manager 5.4 software was used for the data analysis. Six studies with a total of 1, 428 patients met the inclusion criteria.

Results

The incidence of vitamin D insufficiency in patients with idiopathic scoliosis was 36.19% (95% CI [21.93 to 50.46]. In contrast, the incidence of vitamin D deficiency was 41.43% (95% CI [16.62 66.23]. Vitamin D levels were compared between Caucasian and African patients and it was concluded that Caucasian patients had a lower risk of vitamin D deficiency [RR 0.15, 95% CI (0.03 to 0.82; P = 0.03]. There was also an association between patients with idiopathic scoliosis and lower vitamin D -5.58, 95% CI [-7.10, -4.06]. Finally, no significant differences were observed in terms of curve magnitude assessed with the Cobb angle mean difference (MD) 4.45, 95% CI [-0.55, 9.44], or sex with lower-than-normal levels of vitamin D OR 0.96, 95% CI [0.58 to 1.60].

Discussion

The incidence rates of vitamin D insufficiency and deficiency in patients with adolescent idiopathic scoliosis were 36.19% and 41.43%, respectively. The Caucasian race was associated with a lower risk of vitamin D deficiency compared to the African race. Vitamin D deficiency was not related to curve magnitude or sex.

Association of Serum Vitamin D With Periodontal Disease

OBJECTIVE

There are conflicting reports on the relationship between vitamin D and periodontal disease. Our research is intended to further analyse the association between serum 25(OH)D3, a vitamin D precursor and periodontal disease based on a large national survey sample in Japan.

METHODS

We downloaded the 2009-2018 National Health and Nutrition Examination Survey (NHANES) cycle, which included a total of 23,324 samples. Logistic regression of factors influencing perioral disease including periodntal disease, and subgroup logistic regression were performed to analyse the relationship between serum vitamin D and perioral disease, using WTMEC2YR as weights for regression analysis. Then machine learning model-based prediction of perioral disease onset was performed, and the machine learning algorithms used included boost tree, artificial neural network, AdaBoost, and random forest.

RESULTS

We evaluated the vitamin D, age, sex, race, education, marriage, body mass index, ratio of family income to poverty (PIR), smoking, alcohol consumption, diabetes, and hypertension as variables in the included samples. Vitamin D was negatively associated with perioral disease; compared with Q1, the odds ratios and 95% CI were 0.8 (0.67-0.96) for Q2, 0.84 (0.71-1.00) for Q3, and 0.74 (0.6-0.92) for Q4 (P for trend <.05), respectively. The results of the subgroup analysis showed that the effect of 25(OH)D3 on periodontal disease was more pronounced in women younger than 60 years. Based on the accuracy and receiver operating characteristic curve, we concluded that a boost tree was a relatively good model to predict periodontal disease.

CONCLUSIONS

Vitamin D might be a protective factor for periodontal disease, and boost tree analysis we emplyed was a relatively good model to predict perioral disease.

Association between patterns of nutrient intake and circulating vitamin D with sleep status among Iranian adults

Nutrient pattern analysis is an easy way to compare nutrient intakes across different nations due to the universality of nutrients nature. The purpose of this study was to examine the relationship between dietary nutrient patterns (NPs) and circulating 25(OH)D concentrations with sleep duration and sleep quality among Iranian adults. We used a multistage cluster random sampling method to enroll 535 adults in this cross-sectional investigation. A validated food frequency questionnaire was applied to evaluate typical dietary intakes. Fasting blood samples were obtained to determine levels of circulating 25(OH)D. Sleep characteristics were assessed using the Pittsburgh Sleep Quality Index (PSQI). Participants had a mean age of 42.57 years and 51.2% of them had insufficient or deficient levels of serum vitamin D. Three NPs were identified: "high animal protein", "high vegetable" and "high carbohydrate". After adjustments for potential confounders, no significant associations were observed between "high animal protein" pattern and short sleeping or sleep quality. Greater adherence to "high vegetable" NP was associated with lower odds of short sleeping (OR 0.24; 95% CI 0.10, 0.54) and poor sleep quality (OR 0.45; 95% CI 0.20, 1.05). Stratified analysis revealed that these associations were stronger in normal-weight participants. Greater adherence to "high carbohydrate" NP, on the other hand, was connected to higher odds of short sleeping (OR 2.83; 95% CI 1.20, 6.72). Low adherence to "high vegetable" pattern and vitamin D insufficiency/deficiency were jointly associated with increased odds of short sleeping (OR 3.42, 95% CI 1.42, 6.64). High adherence to pattern comprising mainly of vegetable nutrients was associated with a reduced likelihood of being short sleepers and having poor sleep quality in Iranian adults, especially among those with a normal weight. Lower adherence to vegetable NP and insufficient/deficient vitamin D levels were synergistically associated with greater likelihood of being short sleepers. Greater adherence to carbohydrate NP was associated with an increased likelihood of short sleeping.

Sex and obesity status modify the association between vitamin D and eczema among adolescents

BACKGROUND

Epidemiologic studies have reported inconsistent associations between vitamin D and eczema. This study sought to assess whether sex and obesity status could modify the association between vitamin D and eczema.

METHODS

A cross-sectional study enrolled 763 adolescents in Kuwait. 25-hydroxyvitamin D (25(OH)D) was measured in venous blood. Current eczema was defined according to clinical history and characteristic morphology and distribution.

RESULTS

In sex-stratified analysis, decreased 25(OH)D levels were associated with increased current eczema prevalence among males (adjusted odds ratio (aOR)tertile 1 vs. tertile 3: 2.14, 95% confidence intervals (CI): 1.07-4.56), but not among females (aORtertile 1 vs. tertile 3: 1.08, 95% CI: 0.71-1.66). Further stratification by obesity status showed that lower 25(OH)D levels were associated with increased current eczema prevalence among overweight/obese males (per 10-unit decrease in 25(OH)D levels: aOR: 1.70, 95% CI: 1.17-2.46). Such an association was weaker and statistically non-significant among overweight/obese females (per 10-unit decrease in 25(OH)D levels: aOR: 1.26, 95% CI: 0.93-1.70).

CONCLUSIONS

Sex and obesity status modified the association between vitamin D levels and eczema, with an inverse association observed among overweight/obese males, but not among overweight/obese females. These results suggest that preventive and clinical management strategies could vary by sex and obesity status.

IMPACT

The current study showed that sex and obesity modify the association between vitamin D and eczema among adolescents. An inverse association between vitamin D and eczema was observed among overweight/obese males, but this association was not as pronounced among overweight/obese females. Vitamin D was not associated with eczema among underweight/normal weight males and females. The identification of effect modification by sex and obesity status add to the current scientific knowledge and further highlight the complexity of the association between vitamin D and eczema. These results may promote a more individualized approach to the future prevention and clinical management of eczema.

25-hydroxyvitamin D concentration is positively associated with overall survival in advanced pancreatic cancer: A systematic review and meta-analysis

Studies have shown that 25-hydroxyvitamin D (25(OH)D) is predictive of survival following a diagnosis of cancer. However, evidence of the relationship between 25(OH)D and the survival of patients with pancreatic cancer has been inconsistent. We hypothesized that circulating 25(OH)D concentrations may be positively correlated with better prognosis in advanced pancreatic cancer. PubMed, EMBASE, Cochrane Library, and Web of Science database entries through April 2023, along with the reference lists of related studies, were searched. Additionally, we extracted observational studies reporting the association between 25(OH)D concentrations and the outcome of interest (overall survival [OS]) in advanced pancreatic cancer patients aged 18 years or older. Ultimately, 7 articles involving 2369 patients were included in this systematic review and meta-analysis. The results indicated that 25(OH)D concentrations were positively correlated with OS (hazard ratio = 2.37; 95% confidence interval, 2.22-2.54; P < .001). No association was found between 25(OH)D and progression-free survival. There was significant heterogeneity between studies in terms of OS (I2 = 85.5%, P < .001). Our subgroup analysis revealed that this high heterogeneity may be attributed to the studies' different regions, designs, sample sources, and detection methods of 25(OH)D. Additionally, Begg's and Egger's tests indicated the presence of publication bias. To our knowledge, this is the first meta-analysis to evaluate the association between 25(OH)D concentrations and OS among patients with pancreatic cancer. Our results suggested that circulating 25(OH)D concentrations were positively correlated with OS, indicating that 25(OH)D may be a potential prognostic marker in advanced pancreatic cancer.

Sex differences in vitamin D and behavioral profiles among children with allergic diseases

Previous studies have suggested that vitamin D has a protective effect on allergic diseases, while an individual's sex may have a moderating effect on the relationship between vitamin D and allergic-related immunity. This study aimed to determine the role of vitamin D in children with coexisting allergic diseases in the context of sex differences and to explore the behavioral profiles of these patients. We recruited a total of 103 children with atopic diseases and divided them into four groups: males with one allergic disease (MA1, n = 20), males with two or more allergic diseases (MA2, n = 26), females with one allergic disease (FA1, n = 30), and females with two or more allergic diseases (FA2, n = 27). We measured serum calcium levels using the colorimetric method and serum 25-OH vitamin D total levels using electrochemiluminescence immunoassay. We found that MA2 had significantly lower vitamin D levels than MA1 and FA2. The levels of IgE were negatively correlated with vitamin D in females, whereas the levels of IgE were not significantly correlated with vitamin D in males. Furthermore, serum IgE was significantly correlated with children's adaptive skills, and different sexes were associated with different aspects of adaptive skills. Our findings suggest a protective role of vitamin D in the development of one allergic disease against the coexistence of allergic diseases in males, as well as extend the evidence for sex differences in immunity by demonstrating a sex-different correlation between IgE and vitamin D and the relationship between IgE and children's adaptive skills.

Parenteral Nutrition in the Pediatric Oncologic Population: Are There Any Sex Differences?

Gender-based medicine is attracting increasing interest every day, but studies on pediatric populations are still limited. In this setting, sex differences among patients undergoing total parenteral nutrition (TPN) have not been previously reported. This study investigated the presence of sex differences in parenteral nutrition composition and outcomes among a cohort of pediatric patients admitted at the Oncohematology and Bone Marrow Transplant Unit of the Institute for Maternal and Child Health "Burlo Garofolo" of Trieste, Italy. For all 145 recruited patients (87 males, 58 females), the following data were collected: age, sex, volume and duration of TPN, macro- and micronutrient composition of TPN bags, electrolytic or blood gases imbalance, glycolipid alterations, liver damage during TPN, and the incidence of sepsis and thrombosis. The analysis showed that females required higher daily phosphate intake (p = 0.054) and essential amino acid supplementation (p = 0.07), while males had a higher incidence of hypertriglyceridemia (p < 0.05) and cholestasis. A higher incidence of sepsis was found in the non-transplanted male population (p < 0.05). No significant differences were appreciable in other analyzed variables. This study aims to create a basis for future gender-based nutritional recommendations in the pediatric field.

Impact of Vitamin D on Immunopathology of Hashimoto's Thyroiditis: From Theory to Practice

Hashimoto's thyroiditis (HT) is a common autoimmune disease affecting the thyroid gland, characterized by lymphocytic infiltration, damage to thyroid cells, and hypothyroidism, and often requires lifetime treatment with levothyroxine. The disease has a complex etiology, with genetic and environmental factors contributing to its development. Vitamin D deficiency has been linked to a higher prevalence of thyroid autoimmunity in certain populations, including children, adolescents, and obese individuals. Moreover, vitamin D supplementation has shown promise in reducing antithyroid antibody levels, improving thyroid function, and improving other markers of autoimmunity, such as cytokines, e.g., IP10, TNF-α, and IL-10, and the ratio of T-cell subsets, such as Th17 and Tr1. Studies suggest that by impacting various immunological mechanisms, vitamin D may help control autoimmunity and improve thyroid function and, potentially, clinical outcomes of HT patients. The article discusses the potential impact of vitamin D on various immune pathways in HT. Overall, current evidence supports the potential role of vitamin D in the prevention and management of HT, although further studies are needed to fully understand its mechanisms of action and potential therapeutic benefits.

Clarifying the Heterogeneity in Response to Vitamin D in the Development, Prevention, and Treatment of Type 2 Diabetes Mellitus: A Narrative Review

In this review, we explore the potential drivers of heterogeneity in response to Vitamin D (VitD) therapy, such as bioavailability, sex-specific response, and autoimmune pathology, in those at risk for and diagnosed with T2DM. In addition, we propose distinct populations for future interventions with VitD. The literature concerning VitD supplementation in the prevention, treatment, and remission of type 2 diabetes mellitus (T2DM) spans decades, is complex, and is often contradictory with mixed findings upon intervention. By association, VitD status is powerfully predictive with deficient subjects reporting greater risk for T2DM, conversion to T2DM from prediabetes, and enhanced response to VitD therapy. Preclinical models strongly favor intervention with VitD owing to the pleiotropic influence of VitD on multiple systems. Additional research is crucial as there remain many questions unanswered that are related to VitD status and conditions such as T2DM. Future research must be conducted to better understand the potentially spurious relationships between VitD status, supplementation, sun exposure, health behaviors, and the diagnosis and management of T2DM. Public health practice can greatly benefit from a better understanding of the mechanisms by which we can reliably increase VitD status and how this can be used to develop education and improve health behaviors.

Plasma 25-Hydroxyvitamin D Level and VDR Gene Single Nucleotide Polymorphism rs2228570 Influence on COVID-19 Susceptibility among the Kazakh Ethnic Group-A Pilot Study

Low plasma levels of the vitamin D metabolite 25-hydroxyvitamin D [25(OH)D] and the vitamin D receptor (VDR) gene single nucleotide polymorphisms (SNPs) have been associated with the body's susceptibility to infectious diseases, including COVID-19. In this pilot retrospective study, representatives of the Kazakh population (central Kazakhstan) were divided into groups based on the test for IgM and IgG for coronavirus infection. We compared the 25(OH)D plasma levels and concluded that the COVID-19-positive group values (25.17 ng/mL ± 16.65) were statistically lower (p = 0.0114) compared to the COVID-19-negative ones (35.58 ng/mL ± 20.67). There was no association between age, gender and 25(OH)D concentration within the groups (p > 0.05). The genotyping of rs2228570 was performed using a TaqMan Real-Time PCR assay. Allele C predominated among the COVID-19-negative participants and significantly reduced the likelihood of coronavirus infection (p < 0.0001; OR = 0.0804; 95% CI 0.02357-0.2798). There were no statistically significant differences in the frequencies of the A, G and T alleles in the studied groups (p > 0.05). The GG genotype of rs2228570 was associated with a 4.131-fold increased likelihood of COVID-19 infection (p = 0.0288; χ2 = 5.364; OR = 4.131; 95% CI 1.223-13.71). Comprehensive studies are required to determine whether low 25(OH)D plasma concentrations and genetic background represent a risk factor for COVID-19 infection.

25-hydroxyvitamin D level is associated with greater grip strength across adult life span: a population-based cohort study

OBJECTIVE

Maintaining muscle function throughout life is critical for healthy ageing. Although in vitro studies consistently indicate beneficial effects of 25-hydroxyvitamin D (25-OHD) on muscle function, findings from population-based studies remain inconclusive. We therefore aimed to examine the association between 25-OHD concentration and handgrip strength across a wide age range and assess potential modifying effects of age, sex and season.

METHODS

We analysed cross-sectional baseline data of 2576 eligible participants out of the first 3000 participants (recruited from March 2016 to March 2019) of the Rhineland Study, a community-based cohort study in Bonn, Germany. Multivariate linear regression models were used to assess the relation between 25-OHD levels and grip strength while adjusting for age, sex, education, smoking, season, body mass index, physical activity levels, osteoporosis and vitamin D supplementation.

RESULTS

Compared to participants with deficient 25-OHD levels (<30 nmol/L), grip strength was higher in those with inadequate (30 to <50 nmol/L) and adequate (≥50 to ≤125 nmol/L) levels (ßinadequate = 1.222, 95% CI: 0.377; 2.067, P = 0.005; ßadequate = 1.228, 95% CI: 0.437; 2.019, P = 0.002). Modelling on a continuous scale revealed grip strength to increase with higher 25-OHD levels up to ~100 nmol/L, after which the direction reversed (ßlinear = 0.505, 95% CI: 0.179; 0.830, P = 0.002; ßquadratic = -0.153, 95% CI: -0.269; -0.038, P = 0.009). Older adults showed weaker effects of 25-OHD levels on grip strength than younger adults (ß25OHDxAge = -0.309, 95% CI: -0.594; -0.024, P = 0.033).

CONCLUSIONS

Our findings highlight the importance of sufficient 25-OHD levels for optimal muscle function across the adult life span. However, vitamin D supplementation should be closely monitored to avoid detrimental effects.

Effects of vitamin D supplementation on the regulation of blood lipid levels in prediabetic subjects: A meta-analysis

This meta-analysis aimed to systematically investigate whether vitamin D supplementation reduces blood lipid—total cholesterol (TC), LDL cholesterol (LDL-C), HDL cholesterol (HDL-C), and triglyceride (TG)—levels in prediabetic individuals. Pubmed, Web of Science, Cochrane Library, Embase, CNKI, and WANFANG databases were searched for studies published before 13 February 2022 (including 13 February 2022). Five articles were included. The results showed that vitamin D intervention led to a significant reduction in TG compared with control or placebo treatment (−0.42 [−0.59, −0.25], P &lt; 0.001). Subgroup analyses showed that this effect was particularly significant among the studies that included obese subjects (−0.46 [−0.65, −0.28], P &lt; 0.001), the studies that also included men (not only women) (−0.56 [−0.78, −0.34], P &lt; 0.001), and the studies with intervention durations longer than 1 year (−0.46 [−0.65, −0.28], P &lt; 0.001). Both relatively low doses of 2,857 IU/day (−0.65 [−0.92, −0.38], P &lt; 0.001) and relatively high doses of 8,571 IU/day (−0.28 [−0.54, −0.02] P = 0.04) of vitamin D supplementation reduced TG levels, and the effect was observed both in Northern Europe (−0.65 [−0.92, −0.38], P &lt; 0.001) and Asian (−0.25 [−0.48, −0.03], P = 0.03) country subgroups. No significant effects on TC, HDL-C, and LDL-C were shown. In conclusion, vitamin D supplementation might beneficially affect TG levels in individuals with prediabetes. Particularly longer durations of treatment, more than 1 year, with doses that correct vitamin deficiency/insufficiency, can have a beneficial effect. This meta-analysis was registered at www.crd.york.ac.uk/prospero (CRD42020160780).

Longitudinal changes in vitamin D concentrations and the association with type 2 diabetes mellitus: the Tromsø Study

AIM

We aimed to investigate the relationship between pre- and post-diagnostic 25-hydroxyvitamin D (25(OH)D) concentrations and type 2 diabetes (T2DM) over a period of 30 years in individuals who developed T2DM compared to healthy controls.

METHODS

This case-control study included 254 participants with blood samples collected at five different time-points (T1-T5) between 1986 and 2016. Of the 254 participants, 116 were diagnosed with T2DM between T3 and T4, and were considered cases; the remaining 138 were controls. Linear mixed regression models were used to examine pre- and post-diagnostic changes in 25(OH)D concentrations, and logistic regression was used to examine associations between these concentrations and T2DM at each time-point.

RESULTS

25(OH)D concentrations at different time-points and the longitudinal change in concentrations differed between cases and controls, and by sex. For women, each 5-nmol/l increase in 25(OH)D concentrations was inversely associated with T2DM at T3 (odds-ratio, OR, 0.79), whereas for men, this same increase was positively associated with T2DM at T1 (OR 1.12). Cases experienced a significant decrease in pre-diagnostic 25(OH)D concentrations (p value < 0.01 for women, p value = 0.02 for men) and a significant increase in post-diagnostic 25(OH)D concentrations (p value < 0.01 for women, p value = 0.01 for men). As such, each 1-unit increase in month-specific z-score change between T1 and T3 was significantly inversely associated with T2DM (OR 0.51 for women, OR 0.52 for men), and each such increase between T3 and T5 was significantly positively associated with T2DM in women (OR 2.48).

CONCLUSIONS

25(OH)D concentrations seem to be affected by disease progression and type 2 diabetes diagnosis.

The antidepressant-like effect elicited by vitamin D3 is associated with BDNF/TrkB-related synaptic protein synthesis

Vitamin D₃ (cholecalciferol) has been shown to exert antidepressant-like responses, but the role BDNF/TrkB-related synaptic plasticity in this effect remains to be established. Thus, this study investigated the time-course antidepressant-like response of vitamin D₃ in female and male mice and the possible role of BDNF/TrkB signaling in this response. The repeated (7 and 21 days), but not acute (60 min), administration of vitamin D₃ (2.5 μg/kg, p.o.) exerted an antidepressant-like effect in female and male mice subjected to the tail suspension test, without altering the basal locomotor activity in the open-field test. Notably, vitamin D₃ caused a similar time-dependent antidepressant-like effect in male and female mice, suggesting that this behavioral response in the tail suspension test might not be affected by sex differences. Vitamin D₃ administration for 21 days, but not for 7 days or 1 h, augmented BDNF levels in the hippocampus and prefrontal cortex of mice. No effects on phospho-CREB/CREB levels were detected in the hippocampus and prefrontal cortex after chronic vitamin D₃ administration. Additionally, vitamin D₃ increased TrkB, GluA1, and PSD-95 levels in the prefrontal cortex, but not in the hippocampus. Furthermore, an upregulation of synapsin level was observed in both brain regions after vitamin D₃ administration. These findings reinforce and extend the notion that vitamin D₃ is effective to produce antidepressant-like responses in male and female mice and provide novel evidence that this effect could be associated with BDNF/TrkB-related synaptic protein synthesis. Finally, vitamin D₃ could be a feasible nutritional strategy for the management of depression.

Factors Associated with Potentially Inappropriate Screening for Vitamin D Deficiency among Women in Medically Underserved Regions of West Texas

Testing for vitamin D deficiency (VDD) has been on the increase due to its association with several diseases. However, inappropriate testing for VDD, defined as screening for VDD among individuals with a low risk, has been reported. The aim of this study was to evaluate the prevalence and factors associated with potentially inappropriate screening for VDD among medically underserved populations in West Texas. Data were from 21,407 women who were hospitalized from 2016 to 2018 at a large regional health system. Logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). The median age of patients was 40 years. While the proportion of patients tested for VDD reduced from 8.9% to 7.6% (p = 0.013) from 2016 to 2018, the prevalence of inappropriate testing increased from 32.3% to 46.8% (p < 0.001), with the 3-year prevalence of VDD being 27.6%. White race (OR = 2.71, CI: 1.95-3.78), an age ≥ 65 years (OR = 3.07, CI: 2.05-4.59), the use of public-sponsored insurance (OR = 1.62, CI: 1.20-2.17), cardiovascular disease (OR = 0.75, CI: 0.63-0.90), and vitamin D supplement use (OR = 7.05, CI: 5.82-8.54) were associated with inappropriate testing for VDD. In this study, an increasing prevalence of potentially inappropriate testing for VDD was observed. Sociodemographic and health-related conditions were associated with potentially inappropriate testing for VDD.