The vitamin D deficiency pandemic: Approaches for diagnosis, treatment and prevention

Changes in Vitamin D Status in Overweight Middle-Aged Adults with or without Impaired Glucose Metabolism in Two Consecutive Nordic Summers

Background

Sun exposure is the main driver of vitamin D synthesis. High latitude, obesity, and type 2 diabetes mellitus (T2DM) are all risk factors for vitamin D deficiency. However, the seasonal variation in vitamin D concentrations (25[OH]D) in such populations before and after sun exposure during the summer is unknown. Therefore, we investigated 25[OH]D status before and after two consecutive summers in high latitude and its associations with body fat, sex, and glucose metabolism.

Methods

158 participants from Sweden (87 women, 71 men; mean age, 60 ± 5 y; body mass index ≥ 25 kg/m²) and 25[OH]D were measured and evaluated in relation to normal or impaired glucose tolerance, body composition, and dietary habits during summer season.

Results

Eighty-four percent of the participants were categorized with low to deficient 25[OH]D values before summer (55.1 ± 21.7 nmol·L⁻¹), with a significant increase after the summer season (66.3 ± 21.0 nmol·L⁻¹; P < 0.001). However, the values remained below the recommended range (76–250 nmol·L⁻¹) in 66% of the participants. These findings were verified in a subgroup of the study population during the subsequent summer. Participants who reported use of vitamin D supplements had higher initial concentrations (64.2 ± 20.1 nmol·L⁻¹) compared to nonusers (53.7 ± 21.7 nmol·L⁻¹; P=0.04). Further, 25[OH]D values correlated negatively with fat mass (kg) prior to summer only in the female population (r=−0.29,  P=0.008).

Conclusions

In the present study, sun exposure had a beneficial but insufficient effect on 25[OH]D levels, and the same levels were documented in two consecutive summer seasons, confirming that vitamin D supplementation in both summer and winter should be considered in this population.

Contribution of nutrition science to the vitamin D field-Clarity or confusion?

Recent opinion pieces have questioned whether nutrition science is fit for purpose, suggesting that the evidence-base for dietary recommendations is populated with poor quality science and unresolved controversy. Nutrition science is accused of not keeping up with the times and making little real-world progress to stem the growing global malnutrition crisis, by failing to apply cutting-edge techniques to nutrition problems. Nutritional epidemiology has been blamed for harming public health nutrition and the public perception of science itself, by selectively reporting biased, confounded data. Focussed on obesity and associated disorders and hunger, these articles do not refer to micronutrient deficiencies or advances in micronutrient research. There is a serious public health problem of low vitamin D status. Given that the field of vitamin D has experienced an exponential increase in peer-reviewed publications over the last 50 years, it seems timely that we take these cues to reflect upon whether the expanded body of scientific literature has contributed to a deeper knowledge of vitamin D in health and disease, leading to improved nutrition policy and patient care, or whether it has led to so much confusion and controversy that progress has been impeded. We consider whether the accusations of poor science and biased reporting levelled at nutrition science are evident within the vitamin D nutrition research area and whether they have compromised dietary recommendations for vitamin D. In evaluating whether reformation is required, we discuss the confusion and controversy within the field and signpost common ground within the vitamin D community. We outline vitamin D nutrition research that has presented strategies for vitamin D deficiency prevention within the population, particularly using food first approaches that could extend beyond high income settings to low- and middle-income countries. Finally, we encourage government and industry to implement technical advances and drive real-world progress.

Nutrient Composition Comparison between a Modified Paleolithic Diet for Multiple Sclerosis and the Recommended Healthy U.S.-Style Eating Pattern

Multiple sclerosis (MS) is a demyelinating disease that attacks the central nervous system. Evidence-based dietary guidelines do not exist for MS; the default advice is to follow the Dietary Guidelines for Americans (DGA). A modified Paleolithic Wahls Elimination (WahlsElim) diet promoted for MS excludes grains and dairy and encourages 9+ cups fruits and vegetables (F/V) and saturated fat for cooking. This study evaluated the nutritional adequacy of seven-day menus and modeled them with varying amounts of F/V for comparison with the DGA Healthy US-Style Eating Pattern (HEP) for ages 31⁻50 years. WahlsElim menus had low added sugar and glycemic index. Nutritional adequacy of the menus and modeled versions were similar to HEP for 17 vitamins and minerals (mean adequacy ratio ≥92%). Nutrient shortfalls for the modeled diet with 60% F/V were identical to HEP for vitamin D, iron (females), magnesium (marginally males), choline and potassium; this modeled diet was also low in dietary fiber and calcium but met vitamin E requirements while HEP did not. WahlsElim-prescribed supplements corrected vitamin D and magnesium shortfalls; careful selection of foods are needed to meet requirements of other shortfall nutrients and reduce saturated fat and sodium. Doctors should monitor nutritional status, supplement doses, and possible contraindications to high vitamin K intake in individuals following the WahlsElim diet.

Perioperative Serum 25-Hydroxyvitamin D Levels Affect Revision Surgery Rates After Arthroscopic Rotator Cuff Repair

PURPOSE

To examine any association between perioperative serum 25-hydroxyvitamin D levels and failure of arthroscopic rotator cuff repair (RCR) requiring revision surgery.

METHODS

Using a private-payer national insurance database, patients who underwent arthroscopic RCR with perioperative serum 25-hydroxyvitamin D levels recorded were included. Patients were stratified into groups of (1) serum 25-hydroxyvitamin D deficiency (<20 ng/mL), (2) insufficiency (20-30 ng/mL), or (3) sufficient (>30-<150 ng/mL). The primary outcome measure was ipsilateral revision rotator cuff surgery, including revision repair, debridement, or reverse shoulder arthroplasty. A multivariable logistic regression analysis was used to control for patient demographics and comorbidities during comparisons.

RESULTS

A total of 982 patients were included in the study. The rate of revision rotator cuff surgery was significantly higher in patients in the serum 25-hydroxyvitamin D-deficient group (5.88%) compared with the serum 25-hydroxyvitamin D-sufficient control group (3.7%) (odds ratio [OR], 3.1; 95% confidence interval [CI], 1.6-5.8; P = .007). Patients with serum 25-hydroxyvitamin D deficiency (5.88%) also had a significantly higher incidence of revision surgery compared with patients with serum 25-hydroxyvitamin D insufficiency (OR, 2.4; 95% CI, 1.5-3.9; P = .011). There was no significant difference in the incidence of revision surgery in the serum 25-hydroxyvitamin D-insufficient group (4.97%) compared with the serum 25-hydroxyvitamin D-sufficient control group (3.7%) (OR, 1.4; 95% CI, 0.8-2.3; P = .250). The absolute risk reduction of revision surgery for 25-hydroxyvitamin D-deficient patients compared with controls was 2.2%, corresponding to a number needed to treat to avoid 1 revision surgery of 46 patients, relative risk reduction = 0.59.

CONCLUSIONS

Although the present study found a significant statistical association between serum 25-hydroxyvitamin D deficiency and insufficiency and the rate of revision rotator cuff surgery after primary arthroscopic RCR, the absolute differences of these revision rates are minimal and are accompanied with overlapping confidence intervals limiting the clinical significance of these findings.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Effect of Vitamin D Supplement on Mood Status and Inflammation in Vitamin D Deficient Type 2 Diabetic Women with Anxiety: A Randomized Clinical Trial

Background:

Vitamin D plays an important role in nervous health and depression. Vitamin D deficiency and anxiety affect diabetic status. The purpose of this study was to determine the effect of vitamin D supplementation on anxiety, depression, and inflammation in diabetic women with anxiety.

Methods:

In this randomized controlled trial, totally 51 women with type 2 diabetes (T2DM) and vitamin D deficiency were randomly allocated to receive one oral pearl of 50,000 IU vitamin D3 (26 women) or a placebo (25 women) fortnightly for 16 weeks. Anthropometric indices, sun exposure, dietary intake, depression, anxiety, and stress scores and biochemical biomarkers including high sensitivity C-reactive protein (hs-CRP) and interleukin-10 (IL-10) were measured at the baseline and after 16-week supplementation.

Results:

Mean ± SD age of participant was 47.43 ± 9.57 years old. Baseline values were not different between the groups. Anxiety score changes were significantly lower in vitamin D group than the controls (P = 0.001). Within group comparison indicated that depression in supplement group with lower vitamin D levels was significantly reduced. Serum hs-CRP reduced (P = 0.01), while IL-10 concentrations increased (P = 0.04) in the intervention group.

Conclusions:

Vitamin D supplementation can improve mood status and anti-inflammatory biomarkers in female diabetics with anxiety and vitamin D deficiency.

Prevalence of vitamin D deficiency and its relationship with factors associated with recurrent wheezing

Objective:

To determine the prevalence of vitamin D deficiency/insufficiency in children 0-18 years of age with recurrent wheezing and/or asthma residing in the microregion of Viçosa, Minas Gerais, Brazil, and treated at a referral center, and to determine its association with major risk factors for wheezing.

Methods:

A cross-sectional study was performed using a semi-structured questionnaire, which was administered by trained interviewers to the legal guardians of the study participants. Data were obtained regarding general characteristics of recurrent wheezing; general sociodemographic, environmental, and biologic factors; and atopy-related factors. The magnitude of the statistical association was assessed by calculating ORs and their corresponding 95% CIs by using multiple logistic regression.

Results:

We included 124 children in the study. The prevalence of vitamin D deficiency/insufficiency in the sample was 57.3%. Vitamin D deficiency/insufficiency was found to be associated with wheezing in the first year of life, personal history of atopic dermatitis, environmental pollution, and vitamin D supplementation until 2 years of age.

Conclusions:

The prevalence of vitamin D deficiency/insufficiency was high in our sample. Vitamin D concentrations were directly associated with vitamin D supplementation until 2 years of age and were inversely associated with wheezing events in the first year of life, personal history of atopic dermatitis, and environmental pollution.

Review of Two Popular Eating Plans within the Multiple Sclerosis Community: Low Saturated Fat and Modified Paleolithic

The precise etiology of multiple sclerosis (MS) is unknown but epidemiologic evidence suggests this immune-mediated, neurodegenerative condition is the result of a complex interaction between genes and lifetime environmental exposures. Diet choices are modifiable environmental factors that may influence MS disease activity. Two diets promoted for MS, low saturated fat Swank and modified Paleolithic Wahls Elimination (WahlsElim), are currently being investigated for their effect on MS-related fatigue and quality of life (NCT02914964). Dr. Swank theorized restriction of saturated fat would reduce vascular dysfunction in the central nervous system (CNS). Dr. Wahls initially theorized that detailed guidance to increase intake of specific foodstuffs would facilitate increased intake of nutrients key to neuronal health (Wahls™ diet). Dr. Wahls further theorized restriction of lectins would reduce intestinal permeability and CNS inflammation (WahlsElim version). The purpose of this paper is to review the published research of the low saturated fat (Swank) and the modified Paleolithic (Wahls™) diets and the rationale for the structure of the Swank diet and low lectin version of the Wahls™ diet (WahlsElim) being investigated in the clinical trial.

Vitamin D C3-epimer levels are proportionally higher with oral vitamin D supplementation compared to ultraviolet irradiation of skin in mice but not humans

A proportion of circulating 25-hydroxy vitamin D₃ (25(OH)D₃₎) undergoes epimerization to form C3-epi 25(OH)D₃ and C3-epi 1,25(OH)₂D₃. These epimers have less calcaemic activity than non-epimerized metabolites and are not differentiated by many immunoassays when reporting total 25(OH)D₃ levels. This study aimed to compare the effect of exposure to ultraviolet radiation (UVR) and oral vitamin D₃ supplementation on vitamin D C3-epimer levels. C57Bl/6 female mice were fed either vitamin D-sufficient (vitamin D₃ 2000 IU/kg) or -deficient diets (no vitamin D₃) for 4 weeks. Among the vitamin D-deficient group, the shaved backs of half were irradiated daily for 4 days with 1 kJ/m² UVR, followed by twice weekly irradiation for 4 weeks. Despite similar 25(OH)D₃ levels, the UV-irradiated group had a lower proportion of C3-epi 25(OH)D₃ at week 7 (p < 0.05) and week 9 (p < 0.01). C3-epimer concentrations and %C3-epi 25(OH)D₃ were also analysed in serum samples from two human clinical trials. These trials investigated the effect of high dose oral vitamin D₃ supplementation and narrowband UVB phototherapy, respectively. Serum 25(OH)D₃ and the %C3-epi 25(OH)D₃ levels measured at 12 months after oral vitamin D₃ supplementation were not significantly different to those measured at the time of maximal effect of phototherapy (2 months). Thus, the proportion of 25(OH)D₃ that undergoes epimerization is greater with oral vitamin D₃ supplementation than exposure to UVR in mice, but not in humans. This important difference between human and murine vitamin D metabolism warrants consideration when interpreting animal studies.

Vitamin D testing and treatment: a narrative review of current evidence

Vitamin D testing and treatment is a subject of controversial scientific discussions, and it is challenging to navigate through the expanding vitamin D literature with heterogeneous and partially opposed opinions and recommendations. In this narrative review, we aim to provide an update on vitamin D guidelines and the current evidence on the role of vitamin D for human health with its subsequent implications for patient care and public health issues. Vitamin D is critical for bone and mineral metabolism, and it is established that vitamin D deficiency can cause rickets and osteomalacia. While many guidelines recommend target serum 25-hydroxyvitamin D (25[OH]D) concentrations of ≥50 nmol/L (20 ng/mL), the minimum consensus in the scientific community is that serum 25(OH)D concentrations below 25-30 nmol/L (10-12 ng/mL) must be prevented and treated. Using this latter threshold of serum 25(OH)D concentrations, it has been documented that there is a high worldwide prevalence of vitamin D deficiency that may require public health actions such as vitamin D food fortification. On the other hand, there is also reason for concern that an exploding rate of vitamin D testing and supplementation increases costs and might potentially be harmful. In the scientific debate on vitamin D, we should consider that nutrient trials differ from drug trials and that apart from the opposed positions regarding indications for vitamin D treatment we still have to better characterize the precise role of vitamin D for human health.

The role of vitamin D in perinatology. An up-to-date review

The role of vitamin D in perinatology is a subject of major interest in current medicine. There is growing evidence about the role of maternal vitamin D levels in pregnancy outcomes. The aim of this review is to summarize the current literature about the role of vitamin D in perinatology. Evidence from this review suggests associations between low levels of maternal vitamin D and higher risk of certain obstetrical complications. Vitamin D has been found to be related to preeclampsia, gestational diabetes mellitus, low birth weight, and preterm birth. The current literature supports vitamin D supplementation in pregnant women, but more high-quality data are necessary. The problem that remains is how to achieve an optimal 25-hydroxyvitamin D level. To determine the real benefits of vitamin D supplementation in pregnancy, we need high-quality trials in larger groups.

Serum vitamin D levels in Berliners of Turkish descent -a cross-sectional study

BACKGROUND

Vitamin D levels may differ between migrant and non-migrant populations, especially among non-western immigrants living in a country with limited sun exposure such as Germany. This study examined serum vitamin D concentration and associated factors among Berliners with and without Turkish background.

METHODS

Two samples (with and without Turkish roots) were recruited in the inner city of Berlin for a cross-sectional study assessing serum vitamin D concentration. Linear regression analyses were used to examine sociodemographic, lifestyle and medical factors associated with serum vitamin D levels.

RESULTS

In the analyses, we included 537 subjects (39% men and 61% women, age 43.2 ± 12.5 (mean ± standard deviation) years) with and 112 without Turkish background (46% men and 54% women, age 46.7 ± 14.6 years). The Turkish sample had lower mean (95%-Confidence Interval) vitamin D levels than the non-Turkish sample: 22.7 nmol/L (21.5;23.9) vs 34.7 nmol/L (31.9;37.5), p < 0.001. In the Turkish female subgroup, veiled women had considerably lower levels than unveiled women: 14.4 nmol/L (11.5;17.3) vs 24.9 nmol/L (23.1;26.7), p < 0.001. Multivariable regression analysis revealed that among the Berliners of Turkish descent, being active less than 150 min per day, and being overweight/obese were independently associated with a lower vitamin D concentration. In the non-migrant sample besides being overweight and obese, female sex was associated with lower vitamin D concentrations.

CONCLUSIONS

Serum vitamin D levels were considerably low in Berliners of Turkish descent, and especially in veiled women. Potentially modifiable factors of low vitamin D levels were high BMI and low physical activity. These findings should be considered in the development of future public health strategies for subpopulations with Turkish migration background.

Changes in Circulating Levels of 25-hydroxyvitamin D3 in Breast Cancer Patients Receiving Chemotherapy

Cancer treatments, toxicities and their effects on lifestyle, may impact levels of vitamin D. The aim of this study was to determine serum 25-hydroxyvitamin D3 (25(OH)D₃) levels before, directly after and 6 months after chemotherapy in breast cancer patients (n = 95), and a comparison group of women (n = 52) not diagnosed with cancer. Changes in 25(OH)D₃ levels over time were compared using linear mixed models adjusted for age and season of blood sampling. Before start of chemotherapy, 25(OH)D₃ levels were lower in patients (estimated marginal mean 55.8 nmol/L, 95% confidence interval (95%CI) 51.2-60.4) compared to the comparison group (67.2 nmol/L, 95%CI 61.1-73.3, P = 0.003). Directly after chemotherapy, 25(OH)D₃ levels were slightly decreased (-5.1 nmol/L, 95%CI -10.7-0.5, P = 0.082), but ended up higher 6 months after chemotherapy (10.9 nmol/L, 95%CI 5.5-16.4, P < 0.001) compared to pre-chemotherapy values. In women without cancer, 25(OH)D₃ levels remained stable throughout the study. Use of dietary supplements did not explain recovery of 25(OH)D₃ levels after chemotherapy. We reported lower 25(OH)D₃ levels in breast cancer patients, which decreased during chemotherapy, but recovered to levels observed in women without cancer within 6 months after chemotherapy. Suboptimal 25(OH)D₃ levels in the majority of the participants highlight the relevance of monitoring in this vulnerable population.

The GC2 haplotype of the vitamin D binding protein is a risk factor for a low plasma 25-hydroxyvitamin D concentration in a Han Chinese population

Background

The GC haplotype of the vitamin D binding protein (encoded by the GC gene) might be a risk factor to the vitamin D (VD) nutritional status for many populations, while evidences from the Chinese Han population are sparse. We test the association between vitamin D binding protein genotypes and VD status as well as the metabolic parameters of glucose and lipids in a Han Chinese population.

Methods

In a cross-sectional study conducted at a health examination centre (registered in ClinicalTrials.gov as QLS2013), 2641 adults were included and grouped according to their plasma 25-hydroxyvitamin D (25OHD) concentrations as VD deficient (VDD), insufficient (VDI), or sufficient (VDS). The rs7041 and rs4588 genotypes were analysed with a molecular beacon-based qPCR method using blood samples.

Results

Plasma 25OHD concentrations were lower in the GC2/2, rs7041T/T, and rs4588A/A genotypes than the GC1f/1s, rs7041G/T, and rs4588C/C genotypes (P <  0.05). After adjusting for confounders, the GC2 haplotype increased the risk of low VD status (P <  0.05) in both genders. More genotypic models revealed the negative contributions of rs4588A than rs7041T to low VD status (P <  0.05). The combined rates of VDD and VDI were 80.2% in males and 86.1% in females. Compared with VDI, VDS, or both, VDD showed higher plasma concentrations of fasting blood glucose, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides in males (P <  0.05); however, no significant differences were found with regard to these parameters between the subgroups defined by the GC genotypes (P > 0.05).

Conclusions

In a Han Chinese population, the GC2 haplotype or more exactly rs4588A is a risk factor for low VD status but is not associated with glucose and lipid metabolic disorders, which are inversely correlated with the circulating 25OHD concentration in males.

Trial registration

The study was retrospectively registered in January 2018 as NCT03406234 in the ClinicalTrials.gov online system.

Electronic supplementary material

The online version of this article (10.1186/s12986-019-0332-0) contains supplementary material, which is available to authorized users.

Controversies Surrounding Vitamin D: Focus on Supplementation and Cancer

There has recently been a huge number of publications concerning various aspects of vitamin D, from the physiological to therapeutic fields. However, as a consequence of this very fast-growing scientific area, some issues still remain surrounded by uncertainties, without a final agreement having been reached. Examples include the definitions of vitamin D sufficiency and insufficiency, (i.e., 20 vs. 30 ng/mL), the relationship between 25-hydroxyvitamin D (25(OH)D) and parathyroid hormone, (i.e., linear vs. no linear), the referent to consider, (i.e., total vs. free determination), the utility of screening versus universal supplementation, and so on. In this review, the issues related to vitamin D supplementation in subjects with documented hypovitaminosis, and the role of vitamin D in cancer will be concisely considered. Daily, weekly, or monthly administration of cholecalciferol generally leads to essentially similar results in terms of an increase in 25(OH)D serum levels. However, we should also consider possible differences related to a number of variables, (i.e., efficiency of intestinal absorption, binding to vitamin D binding protein, and so on). Thus, adherence to therapy may be more important than the dose regimen chosen in order to allow long-term compliance in a sometimes very old population already swamped by many drugs. It is difficult to draw firm conclusions at present regarding the relationship between cancer and vitamin D. In vitro and preclinical studies seem to have been more convincing than clinical investigations. Positive results in human studies have been mainly derived from post-hoc analyses, secondary end-points or meta-analyses, with the last showing not a decrease in cancer incidence but rather in mortality. We must therefore proceed with a word of caution. Until it has been clearly demonstrated that there is a causal relationship, these positive “non-primary, end-point results” should be considered as a background for generating new hypotheses for future investigations.

Daily Nutritional Supplementation with Vitamin D₃ and Phenylbutyrate to Treatment-Naïve HIV Patients Tested in a Randomized Placebo-Controlled Trial

Poor nutritional status is common among human immunodeficiency virus (HIV)-infected patients including vitamin D (vitD₃) deficiency. We conducted a double-blinded, randomized, and placebo-controlled trial in Addis Ababa, Ethiopia, to investigate if daily nutritional supplementation with vitD₃ (5000 IU) and phenylbutyrate (PBA, 2 × 500 mg) could mediate beneficial effects in treatment-naïve HIV patients. Primary endpoint: the change in plasma HIV-1 comparing week 0 to 16 using modified intention-to-treat (mITT, n = 197) and per-protocol (n = 173) analyses. Secondary endpoints: longitudinal HIV viral load, T cell counts, body mass index (BMI), middle-upper-arm circumference (MUAC), and 25(OH)D₃ levels in plasma. Baseline characteristics were detectable viral loads (median 7897 copies/mL), low CD4⁺ (median 410 cells/µL), and elevated CD8⁺ (median 930 cells/µL) T cell counts. Most subjects were vitD₃ deficient at enrolment, but a gradual and significant improvement of vitD₃ status was demonstrated in the vitD₃ + PBA group compared with placebo (p < 0.0001) from week 0 to 16 (median 37.5 versus 115.5 nmol/L). No significant changes in HIV viral load, CD4⁺ or CD8⁺ T cell counts, BMI or MUAC could be detected. Clinical adverse events were similar in both groups. Daily vitD₃ + PBA for 16 weeks was well-tolerated and effectively improved vitD₃ status but did not reduce viral load, restore peripheral T cell counts or improve BMI or MUAC in HIV patients with slow progressive disease. Clinicaltrials.gov NCT01702974.

Stabilization of Vitamin D in Pea Protein Isolate Nanoemulsions Increases Its Bioefficacy in Rats

Micronutrient delivery formulations based on nanoemulsions can enhance the absorption of nutrients and bioactives, and thus, are of great potential for food fortification and supplementation strategies. The aim was to evaluate the bioefficacy of vitamin D (VitD) encapsulated in nanoemulsions developed by sonication and pH-shifting of pea protein isolate (PPI) in restoring VitD status in VitD-deficient rats. Weaned male albino rats (n = 35) were fed either normal diet AIN-93G (VitD 1000 IU/kg) (control group; n = 7) or a VitD-deficient diet (<50 IU/kg) for six weeks (VitD-deficient group; n = 28). VitD-deficient rats were divided into four subgroups (n = 7/group). Nano-VitD and Oil-VitD groups received a dose of VitD (81 µg) dispersed in either PPI-nanoemulsions or in canola oil, respectively, every other day for one week. Their control groups, Nano-control and Oil-control, received the respective delivery vehicles without VitD. Serum 25-hydroxyvitamin D [25(OH)VitD], parathyroid hormone (PTH), Ca, P, and alkaline phosphatase (ALP) activity were measured. After one week of treatment, the VitD-deficient rats consuming Nano-VitD recovered from Vitamin D deficiency (VDD) as compared against baseline and had serum 25(OH)VitD higher than the Nano-control. Enhancement in VitD status was followed with expected changes in serum PTH, Ca, P, and ALP levels, as compared against the controls. Stabilization of VitD within PPI-based nanoemulsions enhances its absorption and restores its status and biomarkers of bone resorption in VitD-deficient rats.

The Association between Polymorphisms of Vitamin D Metabolic-Related Genes and Vitamin D3 Supplementation in Type 2 Diabetic Patients

OBJECTIVE

To investigate the effect of single nucleotide polymorphisms (SNPs) of the key genes in vitamin D metabolic pathway on the serum 25(OH)D level after long-term vitamin D₃ supplementation and provide a theoretical basis for rational vitamin D₃ supplementation in diabetic patients with different genetic backgrounds.

METHODS

Patients with type 2 diabetes (T2DM) who met the inclusive criteria were given 800 IU of vitamin D₃ daily for 30 consecutive months. Serum 25(OH)D levels was measured at enrollment and every 6 months after enrollment. The average value of four-time measurements represented individual serum 25(OH)D level during vitamin D₃ supplementation. Multiplex TaqMan genotyping was used to determine the distribution of eight candidate SNPs in genes of DHCR7, CYP2R1, CYP27B1, CYP24A1, and VDR, which are key genes in the vitamin D metabolic pathway, in diabetic patients.

RESULTS

At baseline, the average serum 25(OH)D level was 22.71 ± 6.87 ng/mL, and 17.9% of patients had a ≥30 ng/mL level. During supplementation, the level of 25(OH)D increased significantly at each time point, and the average 25(OH)D level increased to 30.61 ± 5.04 ng/mL; however, there were 44.6% of patients whose serum 25(OH)D levels were still below 30 ng/mL. In the patients with CYP27B1 (rs10877012) G/T genotype, 71.79% achieved sufficient level of 25(OH)D, which was significantly higher than the other two genotypes (P < 0.05). Compared with those with T/T genotype, the RR of the patients with rs10877012 for <30 ng/mL level was 0.544 (95% CI: 0.291-0.917), and the RR after adjusting age and outdoor activity was 0.560 (95% CI: 0.292-0.970).

CONCLUSION

The serum 25(OH)D level in patients with diabetes mellitus after long-term vitamin D₃ supplementation is associated with CYP27B1 polymorphism. Patients with rs10877012 G/T allele have a better response to vitamin D₃ supplementation.

TRIAL REGISTRATION

This trial is registered with ChiCTR-IPC-17012657.

Vitamin D Insufficiency in Overweight and Obese Children and Adolescents

Excessive body weight and obesity in childhood and adolescence are becoming more and more important unfavorable factors that entail extremely adverse consequences and require close attention of physicians of any specialty. Along with the high prevalence of obesity and metabolic syndrome in pediatric patients, children and adolescents in the majority of countries are diagnosed with vitamin D deficiency. Among the non-calcaemic effects of vitamin D, a significant role is played by its impact on the hormonal regulation of glucose metabolism and the synthesis of adipokines by fat tissue. The review presents literature data indicative of a close pathogenic relationship between vitamin D insufficiency and impaired tissue insulin sensitivity. It demonstrates the role of vitamin D insufficiency in immune reactions resulting in development of subclinical inflammation in fat tissue infiltrated with macrophages and lymphocytes. It also shows the role of adipokines, immune system cells and pro-inflammatory cytokines produced by them in the pathogenesis of obesity, as well as the function of vitamin D as an endocrine and paracrine regulator of the process of inflammation in adipose tissue. The relationships between the principal adipokines (leptin, adiponectin, resistin) are revealed in the presence of normal vitamin D content and in vitamin D deficiency. The carbohydrate and lipid metabolism parameters in overweight children and adolescents with vitamin D insufficiency are analyzed. A high prevalence of vitamin D insufficiency in overweight and obese children and adolescents (increasing along with the severity of obesity) is demonstrated. The review also presents the current recommendations for the correction of vitamin D insufficiency and underlines the need for higher cholecalciferol doses to achieve serum calcifediol targets in overweight and obese children and adolescents.

The Role of the Status of Selected Micronutrients in Shaping the Immune Function

OBJECTIVE

This narrative review gives an overview on the essential role of adequate nutrition to an optimally functioning immune defence. Micronutrients act as regulators of the immune response, with the focus of this review on the immunomodulatory effects of the trace elements iron, zinc and selenium, and the vitamins A, D, E, C, B6 and B12 and folic acid.

RESULTS

Iron deficiency especially impairs the Th1 cell-borne cellular immunity. T lymphocytes are also most affected by a deficiency of zinc, needed for their maturation and the balance between the different T cell subpopulations and acting as a redox signal in the regulation of many enzymes. Selenium is also involved in redox reactions as the glutathione peroxidases and other redox enzymes are selenoproteins. Selenium status has shown special effects on cellular immunity and resistance to viral infections. Vitamin A in the form of retinoic acid induces a humoral Th2 cell response via antigen-presenting cells and is involved in maintaining intestinal immune defence and tolerance through its nuclear receptor RAR and via kinase signalling cascades. Immune tolerance is particularly promoted by vitamin D acting through dendritic cells to stimulate the differentiation of regulatory T cells. Vitamin E has antiinflammatory effects and stimulates naïve T cells especially in the elderly. Besides its antioxidative properties, vitamin C has effects on cell signalling and epigenetic regulation. The B vitamins are required for cytotoxic cellular immunity and modulate T cell responses.

CONCLUSION

A diverse diet and regular exposure to sunlight are the best sources for a balanced nutrient supply to maintain an optimal immune defence.

Vitamin D and Type I Diabetes

Vitamin D is a fat-soluble vitamin that plays an important role in bone metabolism but is also endowed with the capability of modulating inflammatory and immune function. Recent studies reported a relationship between low vitamin D levels and several autoimmune diseases such as Type 1 Diabetes. Vitamin D regulates the expression of over 200 genes, also related to immune modulation, suggesting a putative role in these diseases pathogenesis. This review overviews the most recent advances on the association between vitamin D and increased risk of Type 1 Diabetes as well as between vitamin D and either glucose homeostasis or insulin sensitivity. The effects of vitamin D in modulating the immune response and balancing anti-inflammatory cytokines, suggest that vitamin D system may represent an unforeseen target for the design of novel strategies for the treatment of patients with autoimmune diseases and in particular Type 1 Diabetes.

Immunomodulatory Effect of Vitamin D and Its Potential Role in the Prevention and Treatment of Type 1 Diabetes Mellitus-A Narrative Review

Type 1 diabetes mellitus is a chronic autoimmune disease associated with degeneration of pancreatic β-cells that results in an inability to produce insulin and the need for exogenous insulin administration. It is a significant global health problem as the incidence of this disorder is increasing worldwide. The causes are still poorly understood, although it certainly has genetic and environmental origins. Vitamin D formed profusely in the skin upon exposure to sunlight, as well as from dietary sources, exhibits an immunomodulatory effect based on gene transcription control. Indeed, vitamin D can downregulate mechanisms connected with adaptive immunity, induce immunological tolerance and decrease auto-aggression-related inflammation. These properties provide the basis for a preventive and therapeutic role of vitamin D. As many studies have demonstrated, appropriate supplementation with vitamin D reduces the risk of autoimmune diseases, including type 1 diabetes mellitus, and alleviates disease symptoms in patients. The aim of this narrative review is to present the molecular mechanisms for the vitamin D immunomodulatory effect as well as review human clinical studies on the use of vitamin D as adjuvant therapy in type 1 diabetes mellitus.

Relationship between vitamin D and chronic spontaneous urticaria: a systematic review

BACKGROUND

Vitamin D has been reported to be associated with many allergic diseases. There are a limited number of the studies of vitamin D supplementation in patients with chronic spontaneous urticaria (CSU). This study aims to study the relationship between vitamin D and CSU in terms of serum vitamin D levels, and the outcomes of vitamin D supplementation.

METHODS

A literature search of electronic databases for all relevant articles published between 1966 and 2018 was performed. The systematic literature review was done following Preferred Reporting Items for Systematic Reviews and Meta-analysis recommendations.

RESULTS

Seventeen eligible studies were included. Fourteen (1321 CSU cases and 6100 controls) were concerned with serum vitamin D levels in CSU patients. Twelve studies showed statistically significant lower serum vitamin D levels in CSU patients than the controls. Vitamin D deficiency was reported more commonly for CSU patients (34.3-89.7%) than controls (0.0-68.9%) in 6 studies. Seven studies concerned with vitamin D supplementation in CSU patients showed disease improvement after high-dosages of vitamin D supplementation.

CONCLUSION

CSU patients had significantly lower serum vitamin D levels than the controls in most studies. However, the results did not prove causation, and the mechanisms were not clearly explained. Despite the scarcity of available studies, this systematic review showed that a high dosage of vitamin D supplementation for 4-12 weeks might help to decrease the disease activity in some CSU patients. Well-designed randomized placebo-controlled studies are needed to determine the cut-off levels of vitamin D for supplementation and treatment outcomes.

Association Between the 25-Hydroxyvitamin D Status and Physical Performance in Healthy Recreational Athletes

Molecular and clinical studies have linked vitamin D (vitD) deficiency to several aspects of muscle performance. For this retrospective cross-sectional study data from 297 male (M) and 284 female (F) healthy recreational athletes were used to evaluate the prevalence of vitD deficiency in athletes living in Austria and to determine whether serum 25-hydroxyvitamin D (25(OH)D) correlates with maximal (P_max) and submaximal physical performance (P_submax) measured on a treadmill ergometer. The data were controlled for age, season, weekly training hours (WTH), body mass index (BMI) and smoking status. 96 M and 75 F had 25(OH)D levels ≤ 20 ng/mL. 25(OH)D levels showed seasonal variations, but no seasonal differences in P_max and P_submax were detected. M with 25(OH)D levels ≤ 20 ng/mL had significantly lower P_submax (p = 0.045) than those with normal levels. In F no significant differences in P_max or P_submax were detected. Stepwise multiple regression analysis including all covariates revealed significant correlations between 25(OH)D levels and P_max (β = 0.138, p = 0.003) and P_submax (β = 0.152, p = 0.002) in M. Interestingly, for F significant correlations between 25(OH)D and both P_max and P_submax disappeared after adding WTH to the model. In conclusion, our data suggest that 25(OH)D status is associated with physical performance especially in M, while in F, WTH and BMI seem to affect the correlation.

1,25-dihydroxyvitamin-D3 promotes neutrophil apoptosis in periodontitis with type 2 diabetes mellitus patients via the p38/MAPK pathway

BACKGROUND

Abnormal neutrophils are involved in many chronic endocrine diseases, including type 2 diabetes mellitus (T2DM), and in periodontitis (PD), which is a chronic inflammatory disease in which neutrophils play a vital role. The p38 mitogen-activated protein kinase (MAPK) signaling pathway participates in the apoptosis of many inflammatory cells. Additionally, 1,25-dihydroxyvitamin-D3 (1,25VitD3) as a regulator can induce responses to infection and tumor cell apoptosis. However, the effect of 1,25VitD3 in the pathogenic relationship between T2DM and PD remains unclear. The aim of this study was to assess the effect of 1,25VitD3 on neutrophil apoptosis in patients with T2DM and PD and the p38-MAPK-relevant signaling pathway mechanism in this process in vitro.

METHODS

Neutrophils were stained with Wright's stain, and apoptosis was detected by flow cytometry and Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) staining. Apoptosis- and p38-related mRNAs and proteins were examined by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR), Western blotting and ELISA. The internal relationships were analyzed using a linear regression equation and Pearson's correlation coefficient.

RESULTS

The highest rate of neutrophil apoptosis occurred in cultures treated with 10 mol/L 1,25VitD3 in the T2DM-PD group. The apoptosis rate in the T2DM-PD-p38 inhibitor group was higher than that in the healthy control group. Western blot, ELISA and qRT-PCR results showed that the mRNA and protein expression profiles of Caspase-3 and Bax were highly up-regulated and that Bcl-2 was down-regulated in the T2DM-PD-p38 inhibitor group. The expression levels of apoptotic mRNAs and proteins in the T2DM and T2DM-PD groups were significantly higher than those in the T2DM-p38 and T2DM-PD-p38 inhibitor groups. 1,25VitD3-induced neutrophil apoptosis and phosphorylated p38 (p-p38) expression were partially inhibited by the p38 inhibitor. Expression levels of apoptosis-related genes and p-p38 in neutrophils were positively associated with increasing concentrations of 1,25VitD3. p-p38 protein expression was positively associated with the level of serum 1,25VitD3.

CONCLUSION

1,25VitD3 could promote peripheral blood neutrophil apoptosis in patients with T2DM and PD through activation of the p38-MAPK signaling pathway in vitro.

Vitamin D deficiency is associated with hepatic decompensation and inflammation in patients with liver cirrhosis: A prospective cohort study

Background

Vitamin D is required to maintain the integrity of the intestinal barrier and inhibits inflammatory signaling pathways.

Objective

Vitamin D deficiency might be involved in cirrhosis-associated systemic inflammation and risk of hepatic decompensation in patients with liver cirrhosis.

Methods

Outpatients of the Hepatology Unit of the University Hospital Frankfurt with advanced liver fibrosis and cirrhosis were prospectively enrolled. 25-hydroxyvitamin D (25(OH)D₃) serum concentrations were quantified and associated with markers of systemic inflammation / intestinal bacterial translocation and hepatic decompensation.

Results

A total of 338 patients with advanced liver fibrosis or cirrhosis were included. Of those, 51 patients (15%) were hospitalized due to hepatic decompensation during follow-up. Overall, 72 patients (21%) had severe vitamin D deficiency. However, patients receiving vitamin D supplements had significantly higher 25(OH)D₃ serum levels compared to patients without supplements (37 ng/mL vs. 16 ng/ml, P<0.0001). Uni- and multivariate analyses revealed an independent association of severe vitamin D deficiency with the risk of hepatic decompensation during follow-up (multivariate P = 0.012; OR = 3.25, 95% CI = 1.30–8.2), together with MELD score, low hemoglobin concentration, low coffee consumption, and presence of diabetes. Of note, serum levels of C-reactive protein, IL-6 and soluble CD14 were significantly higher in patients with versus without severe vitamin D deficiency, and serum levels of soluble CD14 levels declined in patients with de novo supplementation of vitamin D (median 2.15 vs. 1.87 ng/mL, P = 0.002).

Conclusions

In this prospective cohort study, baseline vitamin D levels were inversely associated with liver-cirrhosis related systemic inflammation and the risk of hepatic decompensation.

Potential Dietary Supplement and Medication Interactions in a Subset of the Older Adult Population Attending Congregate Sites

This study assessed possible dietary supplement-medication interactions of 62 older adults recruited from 8 senior congregate sites in Bexar County, Texas. Dietary supplement and medication use were collected by paper questionnaire and potential supplement-medication interactions were assessed using online databases. The majority of participants reported dietary supplements (77%), non-prescription medication (50%), and prescription medication (73%) use. Fifty percent of participants who reported dietary supplement and medication use were at-risk for a potential supplement-medication interaction, ranging from one to eight potential interactions. Calcium and multivitamin-mineral supplements were the most common dietary supplements with potential medication interactions. Surveyed older adults reported dietary supplements should be reported to a physician (97%), but over 20% believe herbal products are pure (38%) and dietary supplements are risk free (34%) and will not cause harm (22%). In conclusion, regular education and screening of dietary supplement and medication use among older adults is recommended.

Vitamin D3 deficiency in puberty rats causes presynaptic malfunctioning through alterations in exocytotic release and uptake of glutamate/GABA and expression of EAAC-1/GAT-3 transporters

Recent experimental and epidemiologic investigations have revealed that the central nervous system is a target for vitamin D3 action and also linked vitamin D3 deficiency to Alzheimer's and Parkinson's disease, autism and dementia. Abnormal homeostasis of glutamate and GABA and signaling disbalance are implicated in the pathogenesis of major neurological diseases. Here, key transport characteristics of glutamate and GABA were analysed in presynaptic nerve terminals (synaptosomes) isolated from the cortex of vitamin D3 deficient (VDD) rats. Puberty rats were kept at the VDD diet up to adulthood. VDD caused: (i) a decrease in the initial rates of L-[¹⁴C]glutamate and [³H]GABA uptake by plasma membrane transporters of nerve terminals; (ii) a decrease in exocytotic release of L-[¹⁴C]glutamate and [³H]GABA; (iii) changes in expression of glutamate (EAAC-1) and GABA (GAT-3) transporters. Whereas, the synaptosomal ambient levels and Ca²⁺-independent transporter-mediated release of L-[¹⁴C]glutamate and [³H]GABA were not significantly altered in VDD. Vitamin D3 is a potent neurosteroid and its nutritional deficiency can provoke development of neurological consequences changing glutamate/GABA transporter expressions and excitation/inhibition balance. Also, changes in glutamate transport can underlie lower resistance to hypoxia/ischemia, larger infarct volumes and worsened outcomes in ischemic stroke patients with VDD.

Intensive Combination Immunotherapy and Neuroinflammation Resolution in a Child With Anti-PCA-1 (Yo) Paraneoplastic Syndrome and 2 Malignancies

Paraneoplastic cerebellar degeneration is rare and noteworthy in children. In this 7-year-old, it was documented to have occurred within a year of ataxia presentation. The instigating cancer was stage III adrenal adenocarcinoma, remitted after surgical resection at age 2. When her severe ataxia progressed, neuroinflammation was characterized by high cerebrospinal fluid Purkinje cell cytoplasmic antibody type 1 titers, oligoclonal bands, and neurofilament light chain. The immunotherapy strategy was to replace IV methylprednisolone, which lowered Purkinje cell cytoplasmic antibody type 1 titers without clinical improvement, with induction of adrenocorticotropic hormone/intravenous immunoglobulin/rituximab (ACTH/IVIG/rituximab) combination immunotherapy, ACTH/dexamethasone transition, and intravenous immunoglobulin maintenance. She became self-ambulatory and cerebrospinal fluid inflammatory markers regressed. Down syndrome predisposed her to a second cancer, pre-B acute lymphoblastic leukemia, 4 years later. Despite reversible cytosine arabinoside-provoked cerebellar toxicity, the ataxia is stable on monthly intravenous immunoglobulin without relapse, now 5 years after initial diagnosis. This report illustrates the use of cerebrospinal fluid biomarkers to detect, target, and monitor neuroinflammation, and successful combinations of immunotherapy to better the quality of life.

Calcitriol combined with calcium chloride causes apoptosis in undifferentiated adipose tissue-derived human mesenchymal stem cells, but this effect decreases during adipogenic differentiation

Calcitriol, the bioactive hormone of vitamin D, is currently linked to several diseases, such as obesity and gain of adipose mass, due to its liposolubility and, consequently, its sequestration by adipocytes. As rates of obesity continue to increase, research on the biology of weight gain should be encouraged. This study evaluated the effects of calcitriol combined with CaCl₂ on adipose tissue-derived human mesenchymal stem cells. We evaluated the cytotoxicity of the combination by MTT assays, in which undifferentiated cells and cells undergoing adipogenic differentiation were tested for 7 and 14 days. The results demonstrated that the combination of calcitriol at the IC₅₀ and CaCl₂ at the IC₂₀ was effective at reducing the viability of mesenchymal stem cells, but with the progression of cell differentiation towards adipocytes, cell resistance to the cytotoxic effects increased. The percentages of dead cells were 88.29, 57.45 and 28.81% for undifferentiated cells and cells exposed to differentiation medium for 7 and 14 days, respectively. Undifferentiated cells were evaluated for apoptosis in response to the same combination using Annexin V assays, and a possible onset of programmed cell death in undifferentiated cells was detected. Additionally, the combination of the compounds altered the membrane permeability of undifferentiated cells by 16 percentage points and induced cell cycle arrest in S phase due to the accumulation of damage. An evaluation of gene expression revealed the overexpression of the GADD45 and ATM genes and the underexpression of the P21, P53, ATR, BCL-2, EIF2 AK3, IGF1R, DNAse-2, ATF, MAP3K4, ENGO-G, CASP3, CASP7 and CASP8 genes. Our results provide valuable insights into the biology of obesity and may contribute to the development of new anti-obesity therapies focusing on the inhibition of adipose tissue mesenchymal stem cell hyperplasia and adipogenic differentiation.

ABCB1 (P-glycoprotein) regulates vitamin D absorption and contributes to its transintestinal efflux

Efficient intestinal absorption of dietary vitamin D is required in most people to ensure an adequate status. Thus, we investigated the involvement of ATP binding cassette subfamily B member 1 (ABCB1) in vitamin D intestinal efflux. Both cholecalciferol (D₃) and 25-hydroxycholecalciferol [25(OH)D₃] apical effluxes were decreased by chemical inhibition of ABCB1 in Caco-2 cells and increased by ABCB1 overexpression in Griptites or Madin-Darby canine kidney type II cells. Mice deficient for the 2 murine ABCB1s encoded by Abcb1a and Abcb1b genes ( Abcb1^-/-) displayed an accumulation of 25(OH)D₃ in plasma, intestine, brain, liver, and kidneys, together with an increased D₃ postprandial response after gavage compared with controls. 25(OH)D₃ efflux through Abcb1^-/- intestinal explants was markedly decreased compared with controls. This reduction of 25(OH)D₃ transfer from plasma to lumen was further confirmed in vivo in intestine-perfused mice. Docking experiments established that both D₃ and 25(OH)D₃ could bind with high affinity to Caenorhabditis elegans P-glycoprotein, used as an ABCB1 model. Finally, in a group of 39 healthy male adults, a single-nucleotide polymorphism (SNP) in ABCB1 (rs17064) was significantly associated with the fasting plasma 25(OH)D₃ concentration. Thus, we showed here for the first time that ABCB1 is involved in neo-absorbed vitamin D efflux by the enterocytes and that it also contributes to vitamin D transintestinal excretion and likely impacts vitamin D status.-Margier, M., Collet, X., le May, C., Desmarchelier, C., André, F., Lebrun, C., Defoort, C., Bluteau, A., Borel, P., Lespine, A., Reboul, E. ABCB1 (P-glycoprotein) regulates vitamin D absorption and contributes to its transintestinal efflux.

Vitamin D in individuals before onset of rheumatoid arthritis - relation to vitamin D binding protein and its associated genetic variants

Background

Vitamin D has been implicated as being involved in the aetio-pathogenesis of several autoimmune diseases including rheumatoid arthritis (RA). Previous studies present contradictory results. Vitamin D binding protein (DBP), the major transport protein, is also involved in various inflammatory processes. The aim of this study was to investigate the relationship between circulating levels of 25-hydroxyvitamin D [25(OH) D], DBP and polymorphisms in group-specific component (GC) in pre-symptomatic individuals and matched controls within prospective cohorts of the Northern Sweden.

Methods

Blood samples donated to the Medical Biobank prior to the onset of symptoms of RA (n = 515, mean [SD] time before the onset of symptoms 6.2 [9.3] years) and from matched (2:1) population-based controls (n = 267) were used. Plasma 25(OH) vitamin D levels were analyzed using liquid chromatography tandem-mass spectrometry and DBP levels were analyzed using enzyme-linked immunosorbent assay. GC polymorphisms (rs4588 and rs7041) were analyzed with TaqMan assays (Applied Biosystems).

Results

Levels of 25(OH) D or DBP were not statistically different between pre-symptomatic individuals and controls in a crude, or a multiple-adjusted logistic regression model. However, an increased risk for future RA was found in females of DBP (OR 1.014 [95%CI 1.001-1.028]) per 10 mg/L adjusted for carriage of the minor allele of rs4588, in a multiple-adjusted model (p < 0.05).

Conclusions

This study indicated that vitamin D is not associated with the future risk of RA although increasing levels of DBP were however, associated with an increased risk of disease in females carrying the minor allele of a DBP encoding SNP.

Plasma 25-Hydroxy Vitamin D Is Not Associated with Either Cognitive Function or Academic Performance in Adolescents

Several observational studies have reported an association between low levels of vitamin D (VD) and poor cognition in adults, but there is a paucity of data on such an association in adolescents. We investigated the association between VD and cognitive function or academic achievement among 1370 adolescents, who were selected from public middle schools in Kuwait, using stratified multistage cluster random sampling with probability proportional to size. Plasma 25-hydroxy VD (25-OH-D) was measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS). An age-adjusted standard score (ASC), calculated from Raven’s Standard Progressive Matrices test, was used to evaluate cognitive function; academic achievements were extracted from the schools’ records. Data on various covariates were collected from the parents through a self-administered questionnaire and from the adolescents using face-to-face interviews. 25-OH-D was weakly correlated positively with ASC (ρ = 0.06; p = 0.04). Univariable linear regression analysis showed an association between 25-OH-D categories and ASC after adjusting for gender, but adjusting for parental education was sufficient to explain this association. Multivariable analysis showed no association between 25-OH-D and ASC after adjusting for potential confounders whether 25-OH-D was fitted as a continuous variable (p = 0.73), a variable that is categorized by acceptable cutoff points (p = 0.48), or categorized into quartiles (p = 0.88). Similarly, 25-OH-D was not associated with academic performance. We conclude that 25-OH-D is associated with neither cognitive function nor academic performance in adolescents.

Fetuin B links vitamin D deficiency and pediatric obesity: Direct negative regulation by vitamin D

Vitamin D (VD) deficiency (VDD) correlates to obesity, with VD a recognized mediator of metabolic diseases. From a previous proteomic study identifying adiponectin as a link between VDD and pediatric obesity, herein we analysed another protein (SSP2301) increased with VDD. A focused 2D-electrophoretic analysis identified 4 corresponding plasma proteins, with one predicted to be fetuin B (FETUB). FETUB was studied due to its emerging role in metabolic diseases and cytogenetic location (3q27.3) with adiponectin. Results were confirmed in obese children, where plasma FETUB was higher with VDD. A direct effect by 1α,25-(OH)2D3 on hepatocellular FETUB synthesis was observed, with a time and dose dependent reduction. Further, we demonstrated the VD-receptor (VDR) is key, with FETUB "released" with VDR silencing. Finally, VD supplementation (6weeks) to juvenile mice fed a standard diet, reduced plasma FETUB. Only at 22weeks did liver FETUB correspond to plasma FETUB, highlighting the contribution of other VD-responsive tissues. Overall, FETUB is a key protein linking VDD to pediatric obesity. With an emerging role in metabolic diseases, we demonstrate that VD/VDR directly regulate FETUB.

Second edition of SIMPAR's "Feed Your Destiny" workshop: the role of lifestyle in improving pain management

This review is aimed to summarize the latest data regarding pain and nutrition, which have emerged during the second edition of Feed Your Destiny (FYD). Theme presentations and interactive discussions were held at a workshop on March 30, 2017, in Florence, Italy, during the 9th Annual Meeting of Study in Multidisciplinary Pain Research, where an international faculty, including recognized experts in nutrition and pain, reported the scientific evidence on this topic from various perspectives. Presentations were divided into two sections. In the initial sessions, we analyzed the outcome variables and methods of measurement for health claims pertaining to pain proposed under Regulation EC No 1924/2006 of the European Parliament and of the Council of 20 December 2006 on nutrition and health claims made on foods. Moreover, we evaluated how the Mediterranean diet can have a potential impact on pain, gastrointestinal disorders, obesity, cancer, and aging. Second, we discussed the evidence regarding vitamin D as a nutraceutical that may contribute to pain control, evaluating the interindividual variability of pain nature and nurture, and the role of micro-RNAs (miRNAs), polyunsaturated omega 3 fatty acids, and phenolic compounds, with a final revision of the clinical role of nutrition in tailoring pain therapy. The key take-home message provided by the FYD workshop was that a balanced, personalized nutritional regimen might play a role as a synergic strategy that can improve management of chronic pain through a precision medicine approach.

Predicting serum vitamin D concentrations based on self-reported lifestyle factors and personal attributes

Evidence supports the role of vitamin D in various conditions of development and ageing. Serum 25-hydroxyvitamin D (25(OH)D) is the best indicator for current vitamin D status. However, the cost of its measurement can be prohibitive in epidemiological research. We developed and validated multivariable regression models that quantified the relationships between vitamin D determinants, measured through an in-person interview, and serum 25(OH)D concentrations. A total of 200 controls participating in a population-based case-control study in Montreal, Canada, provided a blood specimen and completed an in-person interview on socio-demographic, reproductive, medical and lifestyle characteristics and personal attributes. Serum 25(OH)D concentrations were quantified by liquid chromatography-tandem MS. Multivariable least squares regression was used to build models that predict 25(OH)D concentrations from interview responses. We assessed high-order effects, performed sensitivity analysis using the lasso method and conducted cross-validation of the prediction models. Prediction models were built for users and non-users of vitamin D supplements separately. Among users, alcohol intake, outdoor time, sun protection, dose of supplement use, menopausal status and recent vacation were predictive of 25(OH)D concentrations. Among non-users, BMI, sun sensitivity, season and recent vacation were predictive of 25(OH)D concentrations. In cross-validation, 46-47 % of the variation in 25(OH)D concentrations were explained by these predictors. In the absence of 25(OH)D measures, our study supports that predicted 25(OH)D scores may be used to assign exposure in epidemiological studies that examine vitamin D exposure.

25-Hydroxyvitamin D Testing: Immunoassays Versus Tandem Mass Spectrometry

Vitamin D has been associated with many health conditions. Because of widespread deficiency in the general population, laboratory testing of vitamin D has increased exponentially in recent years. Currently, 25-hydroxyvitamin D (25[OH]D) is considered the best marker of vitamin D status. Automated immunoassays and tandem mass spectrometry are the most widely used assays for the measurement of 25(OH)D. Because a medical decision of vitamin D deficiency and treatment are made based on specific levels, it is important that different 25(OH)D assays are harmonized. Despite standardization efforts, significant differences remain among various methods and laboratories for the measurement of 25(OH)D.

Vitamin D deficiency in patients with cluster headache: a preliminary study

Background

Cluster headache is famous for attacks with seasonal and diurnal periodicity. This diurnal and seasonal variation might be related to sunlight and vitamin D metabolism. We investigated the serum vitamin D levels in patients with cluster headache.

Methods

We enrolled patients with cluster headache and age- and sex-matched migraineurs and normal controls. From October 2016 to March 2018, non-fasting serum 25(OH)D concentrations were measured using a chemiluminescent immunoassay. Vitamin D deficiency was defined as a concentration < 20 ng/mL.

Results

The study enrolled 28 patients with cluster headache, 36 migraineurs, and 36 normal controls. In the patients with cluster headache, the serum 25(OH)D concentration averaged 14.0 ± 3.9 ng/mL and 92.8% had vitamin D deficiency. There was no significant difference among the patients with cluster headache, migraineurs, and controls. In the patients with cluster headache, there was no difference in the serum 25(OH)D concentrations between men and women, cluster and remission periods, first and recurrent attack, presence and absence of daily or seasonal periodicity, and 3-month recurrence. In the 14 patients with seasonal periodicity, patients with periodicity of winter to spring had a trend of lower serum 25(OH)D concentrations than those with periodicity of summer to autumn (12.30 ± 1.58 vs. 16.96 ± 4.69 ng/mL, p = 0.097).

Conclusions

Vitamin D deficiency is common in patients with cluster headache, but the role of vitamin D deficiency is uncertain, except for its seasonal influence.

Electronic supplementary material

The online version of this article (10.1186/s10194-018-0886-7) contains supplementary material, which is available to authorized users.

Vitamin D and Uterine Fibroids-Review of the Literature and Novel Concepts

This article provides a detailed review of current knowledge on the role of vitamin D and its receptor in the biology and management of uterine fibroids (UFs). Authors present ideas for future steps in this area. A literature search was conducted in PubMed using the following key words: "uterine fibroid" and "vitamin D". The results of the available studies, published in English from January 2002 up to April 2018, have been discussed. Vitamin D is a group of steroid compounds with a powerful impact on many parts of the human body. This vitamin is believed to regulate cell proliferation and differentiation, inhibit angiogenesis, and stimulate apoptosis. Nowadays, hypovitaminosis D is believed to be a major risk factor in the development of UFs. In many studies vitamin D appears to be a powerful factor against UFs, resulting in inhibition of tumor cell division and a significant reduction in its size, however, the exact role of this compound and its receptor in the pathophysiology of UFs is not fully understood. According to available studies, vitamin D and its analogs seem to be promising, effective, and low-cost compounds in the management of UFs and their clinical symptoms, and the anti-tumor activities of vitamin D play an important role in UF biology. The synergy between vitamin D and selected anti-UF drugs is a very interesting issue which requires further research. Further studies about the biological effect of vitamin D on UF biology are essential. Vitamin D preparations (alone or as a co-drugs) could become new tools in the fight with UFs, with the additional beneficial pleiotropic effect.

Vitamin D Regulates Maternal T-Helper Cytokine Production in Infertile Women

Vitamin D (VD) deficiency is associated with reproductive failure. However, the relationship between VD and maternal immunity remains unclear. We investigated the clinical efficacy of VD in maternal T-helper (Th) cytokines in 276 infertile women and examined for Th1 and Th2 cells based on the deficient, insufficient, and sufficient serum 25-hydroxyvitamin D3 (25[OH]VD) levels (<12, 12–30, and >30 ng/mL, respectively). Most infertile women had a low-level of VD (87.3%). Immunological tests of pre-/post-VD supplementation were performed in patients who were deficient and insufficient in VD. Of 23 patients, 11 (47.8%) exhibited sufficient VD levels after supplementation. Th1/Th2 cell ratio in patients with insufficient VD was significantly decreased after supplementation (p = 0.004). After supplementation, serum 25(OH)VD levels of the patients: 11 in the sufficient group showed significant decreases in Th1 cell level and Th1/Th2 cell ratio (p = 0.032 and 0.010, respectively), whereas no significant differences in Th1/Th2 cell ratio were recognized in the insufficient group. Furthermore, mid-luteal endometrial biopsies (n = 18) were processed for primary cultures and measured interferon [IFN]-γ and interleukin [IL]-4 in condition media. Decidualizing cultures with 1,25-dihydroxvitamin D3 (1,25[OH]₂VD) decreased IFN-γ. Sufficient VD supplementation in women with insufficient VD may optimize maternal T-helper cytokines during pregnancy via rebalancing the Th1/Th2 cell ratio.

Screening for vitamin D deficiency in a tropical area: results of a sun exposure questionnaire

BACKGROUND

Vitamin D deficiency is pandemic while resources available to measure 25-hydroxyvitamin D (25OHD) are limited. The present study aimed to verify whether sun exposure measured by a structured questionnaire could predict serum 25OHD concentrations in healthy Caucasian individuals living in a tropical area.

METHODS

A cross-sectional study was carried out in subjects living in the greater São Paulo area, Brazil. Two groups of 50 young (20 to 40 years old) and 50 older (60 to 80 years old) subjects (N = 200) answered a structured questionnaire on sun exposure and had blood samples drawn for serum 25OHD concentration measurement during both summer and winter. Anthropometric data were also recorded. Correlation between the questionnaire variables (duration of sun exposure, amount of exposed skin, total sun exposure score - TSES and other data) and serum 25OHD concentration was evaluated.

RESULTS

Mean serum 25OHD concentration was 17.60 ± 7.3 ng/mL with no difference between age groups (p = 0.293). TSES weakly correlated with serum 25OHD levels (r = 0.264; p < 0.001). Separate analyzes by age groups demonstrated that TSES correlated significantly with serum 25OHD concentration only in the older subjects during summer (r = 0.322; p = 0.023). Using linear regression analyses, TSES and body mass index (BMI) were significantly associated with serum 25OHD levels. On the other hand, Receiver operating characteristic (ROC) analysis for TSES showed no significance as a screening tool for vitamin D deficiency (p = 0.172).

CONCLUSION

Sun exposure questionnaire associated with BMI correlates with serum 25OHD concentration with very low accuracy. The use of the questionnaire does not discriminate between vitamin D sufficient and deficient individuals.

Evaluation of 25-Hydroxyvitamin D Levels in Central Anatolia, Turkey

Background/Aim

The aim of this study is to evaluate serum 25-hydroxyvitamin D levels measured within one year at an Education and Research Hospital in Turkey to identify vitamin D insufficiency/deficiency (which is very commonly seen in the society) and to provide a current approach to treatment management.

Materials and Methods

This retrospective descriptive study was carried out by examining the data relating to 35,667 individuals.

Results

Of the individuals participating in the study, 94.47% had a serum 25-hydroxyvitamin D level less than 30 ng/ml, 76.25% had a serum 25-hydroxyvitamin D level less than 20 ng/ml, and 32.20% had a serum 25-hydroxyvitamin D level less than 10 ng/ml. The mean serum 25-hydroxyvitamin D level of all individuals included in the study was 15.2±8.8 ng/ml. The mean serum 25-hydroxyvitamin D level was 14.5±8.8 ng/ml among women and 18.1±8.4 ng/ml among men, respectively (p<0.001).

Conclusion

Vitamin D deficiency/insufficiency is widespread in the world and in Turkey. The data obtained from this study suggest that without measuring serum 25-hydroxyvitamin D level will be cost-effective in every age group (except for those are at risk of toxicity) as in children aged 0-1 year old in Turkey and that making a decision in this direction will make a great contribution to the economy of the country.

The association between the serum level of vitamin D and ischemic heart disease: a study from Jordan

Background

Decreased levels of vitamin D were associated with increased risk of multiple diseases, including cardiovascular diseases. However, there seem to be some discrepancies among the results obtained from different studies. The aim of the present study was to explore the importance of having sufficient serum levels of vitamin D in reducing the incidence and the progression of coronary artery stenosis and ischemic heart disease (IHD).

Methods

Serum levels of vitamin D were measured using radioimmunoassay in 186 Jordanian patients who underwent investigative coronary catheterization. Of these patients, 133 were suffering from coronary artery stenosis. The association between vitamin D levels, coronary stenosis and many risk factors was determined using SPSS software.

Results and conclusions

Interestingly, the current results did not show an association between vitamin D abnormalities and the incidence or the reoccurrence of coronary artery stenosis. Moreover, significant differences were detected in the prevalence of vitamin D abnormalities based on the patient’s gender, and there was a significant association between vitamin D abnormalities and both body mass index and dyslipidemia. However, current results did not show any significant association with other risk factors for IHD. For instance, no association was found with smoking, hypertension, diabetes mellitus, stable and unstable angina or with acute recent myocardial infarction.

Increased rate of osteoporosis, low lean mass, and fragility fractures in COPD patients: association with disease severity

A very high rate of osteoporosis, fractures, and low lean mass was observed in patients with chronic obstructive pulmonary disease (COPD). Disease severity was associated with bone and muscle adverse outcomes, while age ≥ 63.5 years old, low lean mass, higher iPTH, and a T-score below - 2.5 were all associated with higher risk of fracture.

INTRODUCTION

Osteoporosis is frequently neglected in patients with COPD. We aimed at evaluating the rate of osteoporosis, fractures, and low lean mass in patients with COPD.

METHODS

Ninety-nine patients with COPD (53 women, 64.5 ± 9.6 years old, and 46 men, 65.9 ± 8.0 years old) underwent bone densitometry (DXA) with body composition analyses. Healthy individuals (N = 57) not exposed to tobacco matched by sex, age, and body mass index (BMI) were used as controls. Spirometry, routine laboratory workout, and conventional thoracolumbar radiography surveying for vertebral deformities were performed in all patients.

RESULTS

Osteoporosis was found in 40.4% of the COPD patients against only 13.0% of the healthy controls (p = 0.001). Vertebral fractures were seen in 24.4% of the men and 22.0% of the women with COPD. Disease severity (GOLD 3 and 4) was significantly associated with higher risk of vitamin D deficiency (p = 0.032), lower BMD (both men and women at all sites), higher frequency of osteoporosis (in women at all sites), lower skeletal mass index, and higher rate of low lean mass (in both men and women) than healthy controls and COPD patients with milder disease (GOLD 1 and 2). Age was a main predictor of vertebral fractures (OR = 1.164 (1.078-9.297); p < 0.001), while high plasma iPTH (OR = 1.045 (1.005-1.088); p = 0.029) and low ALM (OR = 0.99965 (0.99933-0.99997); p = 0.031) were predictors of non-vertebral fractures.

CONCLUSION

Highly prevalent in COPD, osteoporosis and low lean mass were associated with FEV_1% < 50%. Age, low lean mass, high iPTH, and low bone mass were all significantly associated with fractures in COPD patients.

No improvement in vitamin D status in German infants and adolescents between 2009 and 2014 despite public recommendations to increase vitamin D intake in 2012

Purpose

Vitamin D is a key component for the growth and development of children and adolescents, influencing a multitude of functions. Worldwide epidemiological studies have shown that minimum vitamin D blood levels of ≥ 20.0 ng/ml, often defined as vitamin D sufficiency by international and national nutrition and pediatric organizations, are often not met in practice. In 2012 the D–A–CH (Germany, Austria, Switzerland) nutrition societies increased their vitamin D intake recommendations fourfold from 200 IU (5 µg) to 800 IU (20 µg) per day. The outcome of this study will contribute to answering the question as to whether the new recommendations for increased vitamin D intake improve the highly prevalent vitamin D deficiency status in German children and adolescents.

Methods

For this 6-year study (January 2009–December 2014) carried out in Mülheim an der Ruhr, Germany, healthy children and adolescents (n = 1929, age range 1–17 years, median age 11.0 years, 46.9% female) consulting a pediatric group practice (KIDS4.0) were recruited. Serum 25(OH)D determinations were performed using a competitive chemoluminescence immunoassay (CLIA, DiaSorin).

Results

The median serum vitamin D values for each year from 2009 to 2014 were 18.4, 13.0, 20.8, 16.4, 19.4 and 14.9 ng/ml. The summarized median 25(OH)D serum concentrations between the two time periods 2009–2012 and 2013–2014 after increasing recommendations for vitamin D intake did not show a significant difference (17.0 versus 16.8 ng/ml).

Conclusions

The increased D–A–CH recommendations for vitamin D intake had no influence on vitamin D levels in children and adolescents. The prevalence of vitamin D deficiency has not changed compared to previous studies.

Electronic supplementary material

The online version of this article (10.1007/s00394-018-1717-y) contains supplementary material, which is available to authorized users.

Vitamin D levels correlate with lymphocyte subsets in elderly patients with age-related diseases

Hypovitaminosis D is associated with age-related illnesses, including hypertension, cardiovascular disease (CRVD), cerebrovascular disease (CAD) and type 2 diabetes mellitus (T2DM). In our retrospective observational study, blood samples of elderly healthy controls (n = 461) and patients with age-related diseases (n = 8,621) were subjected to flow-cytometry in order to determine correlations between age-related diseases and cluster of differentiation 4 (CD4), CD8, CD3, and CD19 lymphocyte markers, as well as serum levels of 25-hydroxyvitamin D₂ (25(OH)D₂) and 25-hydroxyvitamin D₃ (25(OH)D₃). More than 70% of the patients in each disease group had total vitamin D < 20 ng/mL (P < 0.001). In CRVD patients, CD3 and CD19 correlated (P < 0.05) with 25(OH)D₃. In CAD patients, CD8, CD4, CD19 and CD4/CD8 correlated (P < 0.05) with 25(OH)D₂, and CD8 correlated (P < 0.05) with 25(OH)D₃. In T2DM and hypertension patients, CD8, CD3, CD19 and CD4/CD8 correlated with 25(OH)D₃. Progressive trends (P < 0.05) towards increased CD8 and CD4/CD8 were observed in vitamin-D-deficient T2DM and hypertension patients. Significant differences (P < 0.05) in CD8 were observed in vitamin-D-deficient CAD patients, whereas significant differences (P < 0.05) in CD8 and CD19 were observed in CRVD patients. Higher CD8 and CD4/CD8 in 25(OH)D-deficient T2DM and hypertension patients suggested a Th1 lymphocyte profile induction. Increases in CD8-positive lymphocytes suggested a similar, less pronounced effect in vitamin-D-deficient CRVD and CAD patients.

Mean platelet volume is associated with serum 25-hydroxyvitamin D concentrations in patients with stable coronary artery disease

There is little published data on the association of platelet function and 25(OH)D concentration. We investigated the associations between mean platelet volume (MPV) and 25(OH)D concentration in patients with stable coronary artery disease. Study population was divided into three groups: group 1-25(OH)D < 10 ng/mL (N = 22), group 2-25(OH)D 10-20 ng/mL (N = 42), and group 3-25(OH)D > 20 ng/mL (N = 14). Study groups shared similar demographics. MPV values were the highest in group 1, moderate in group 2, and the lowest in group 3 (11.1 vs 10.4 vs 9.8 fL P < 0.001). There was a negative correlation between MPV and 25(OH)D (R = - 0.38, P = 0.001). ROC analysis demonstrated a moderate predictive value (AUC 0.70) in identifying the discrimination thresholds of MPV (> 10.5 fL) for vitamin D deficiency and a weak predictive value (AUC 0.65) in identifying the discrimination thresholds of 25(OH)D concentration (≤ 15.5 ng/mL) for the presence of large platelets (MPV over the upper limit of normal). In conclusion, even though the effect of vitamin D on platelet size and function is probably multifactorial, our study provides further evidence linking vitamin D to thrombosis and hemostasis. Platelets are another potential element through which vitamin D deficiency could exert adverse cardiovascular outcomes.