25-Hydroxivitamin D Serum Concentration, Not Free and Bioavailable Vitamin D, Is Associated with Disease Activity in Systemic Lupus Erythematosus Patients

Seasonal vitamin D levels and lupus low disease activity state in systemic lupus erythematosus

BACKGROUND

Seasonal variation and sunlight exposure can impact serum vitamin D levels, potentially influencing lupus symptoms. We investigated seasonal vitamin D levels and their correlation with clinical manifestations and disease activity in systemic lupus erythematosus (SLE).

METHODS

Serum 25(OH) vitamin D3 (25(OH)D3) levels were categorised as deficient (25(OH)D3 < 10 ng/mL), insufficient (10-30 ng/mL) and sufficiency (>30 ng/mL) in participants analysed in winter (n = 407) and summer (n = 377). Logistic regression analysis was performed to assess the impact of vitamin D levels on achieving a lupus low disease activity state (LLDAS), stratified by season.

RESULTS

The mean serum 25(OH)D3 levels differed significantly between the winter and summer measurement groups (22.4 vs. 24.2 ng/mL; p = .018). The prevalences of vitamin D deficiency, insufficiency and sufficiency in the winter group were 12.8%, 66.6% and 20.6%, respectively, compared with 4.5%, 67.9% and 27.6% in the summer group. Achieving LLDAS was highest in the vitamin D sufficiency group (winter: 56.6%, summer: 55%) and lowest in the vitamin D deficiency group (winter: 15.4%, summer: 13.6%), with significant differences (all p < .001). Multivariate analysis identified SLE disease activity index ≤4, normal anti-double-stranded DNA and vitamin D sufficiency as significant factors for achieving LLDAS in both seasons.

CONCLUSIONS

Sufficient vitamin D levels are important for achieving LLDAS in patients with SLE during winter and summer. Therefore, physicians should pay attention to the adequacy of vitamin D levels and consider recommending vitamin D supplementation for patients with vitamin D insufficiency.

Vitamin D level in patients with systemic lupus erythematosus: its relationship to disease course and bone mineral density

OBJECTIVE

To determine vitamin D levels in patients with SLE and evaluate their relationship to bone mineral density (BMD) and the disease course.

METHODS

The study included 101 patients with SLE and 29 individuals in the control group. The study participants were tested for vitamin D level, erythrocyte sedimentation rate (ESR), C reactive protein (CRP), interleukin (IL)-6, osteocalcin (OC) and collagen type I C-terminal telopeptide (CTX), and the dual-energy X-ray absorptiometry was provided to assess BMD in the lumbar spine and the hip.

RESULTS

The mean serum vitamin D level was 18.98±0.88 ng/mL, and women had 25.42% lower vitamin D levels than men (p<0.05). There was no correlation between vitamin D levels and patient's age or disease course. There was a significant inverse correlation between vitamin D levels and cumulative dose of glucocorticoids (r=-0.26) and serum inflammatory markers, particularly CRP (r=-0.39), IL-6 (r=-0.37) and ESR (r=-0.15). Vitamin D level was associated with the bone turnover markers (BTMs). In women of reproductive age with vitamin D deficiency, BMD of the lumbar spine and the hip was 9.5-23.1% higher than in those with no vitamin deficiency, respectively, and the mean lumbar spine Z-score in women of reproductive age with vitamin D insufficiency and deficiency was significantly 2.0 and 2.9 times lower than in patients with normal vitamin D level.

CONCLUSIONS

Hypovitaminosis D is quite common in patients with SLE and is associated with high inflammatory activity (SLE Disease Activity Index, ESR, CRP, IL-6), severity of organ damage (Damage Index), cumulative dose of glucocorticoids, BTM changes (decrease in OC, increase in CTX) and BMD decline. Vitamin D status was not associated with the patient's age or disease course.

Genes and Microbiota Interaction in Monogenic Autoimmune Disorders

Monogenic autoimmune disorders represent an important tool to understand the mechanisms behind central and peripheral immune tolerance. Multiple factors, both genetic and environmental, are known to be involved in the alteration of the immune activation/immune tolerance homeostasis typical of these disorders, making it difficult to control the disease. The latest advances in genetic analysis have contributed to a better and more rapid diagnosis, although the management remains confined to the treatment of clinical manifestations, as there are limited studies on rare diseases. Recently, the correlation between microbiota composition and the onset of autoimmune disorders has been investigated, thus opening up new perspectives on the cure of monogenic autoimmune diseases. In this review, we will summarize the main genetic features of both organ-specific and systemic monogenic autoimmune diseases, reporting on the available literature data on microbiota alterations in these patients.

Vitamin D Receptor (VDR) Genetic Variants: Relationship of FokI Genotypes with VDR Expression and Clinical Disease Activity in Systemic Lupus Erythematosus Patients

Vitamin D (VD) deficiency is more frequent in systemic lupus erythematosus (SLE) patients than in control subjects (CS); genetic variants in the VD receptor (VDR) could contribute to the clinical disease activity. This study was aimed to determine the association of the VDR variants FokI (rs2228570), BsmI (rs1544410), ApaI (rs7975232), and TaqI (rs731236) with susceptibility to the disease, VD status, VDR mRNA expression, and clinical disease activity in SLE patients. A cross-sectional study was conducted in 194 SLE and 196 CS Mexican women. Immunoassays quantified serum calcidiol and calcitriol. Genotyping was performed by allelic discrimination assays and mRNA VDR expression by qPCR. The FokI variant was not in linkage disequilibrium with BsmI, ApaI, and TaqI VDR variants. SLE patient carriers of the TT FokI genotype showed higher clinical disease activity scores. Notably, the mRNA VDR expression was higher in SLE patients vs. CS, in active vs. inactive SLE patients, and in participants of both study groups with vitamin D deficiency, higher calcitriol levels, and TT FokI genotype carriers. In conclusion, the TT FokI VDR genotype was related to high VDR expression and clinical disease activity in systemic lupus erythematosus patients.

An Update on the Effects of Vitamin D on the Immune System and Autoimmune Diseases

Vitamin D intervenes in calcium and phosphate metabolism and bone homeostasis. Experimental studies have shown that 1,25-dihydroxyvitamin D (calcitriol) generates immunologic activities on the innate and adaptive immune system and endothelial membrane stability. Low levels of serum 25-hydroxyvitamin D (25(OH)D) are associated with an increased risk of developing immune-related diseases such as psoriasis, type 1 diabetes, multiple sclerosis, and autoimmune diseases. Various clinical trials describe the efficacy of supplementation of vitamin D and its metabolites for treating these diseases that result in variable outcomes. Different disease outcomes are observed in treatment with vitamin D as high inter-individual difference is present with complex gene expression in human peripheral blood mononuclear cells. However, it is still not fully known what level of serum 25(OH)D is needed. The current recommendation is to increase vitamin D intake and have enough sunlight exposure to have serum 25(OH)D at a level of 30 ng/mL (75 nmol/L) and better at 40–60 ng/mL (100–150 nmol/L) to obtain the optimal health benefits of vitamin D.

Differential distribution of vitamin D receptor (VDR) gene variants and its expression in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disorder that displays an important genetic background. Vitamin D₃ (VD₃ ) through its receptor (VDR) plays an important immunomodulatory role in autoimmune misbalance, being capable of modulating immune responses. Genetic alterations in VDR gene may contribute to an altered risk in SLE development and clinical manifestations. We investigated VDR SNPs (single nucleotide polymorphisms) frequencies in 128 SLE patients and 138 healthy controls (HC) and mRNA differential expression in 29 patients and 17 HC regarding SLE susceptibility as well as clinical features. We observed that rs11168268 G allele (OR = 1.55, p = .01) and G/G genotype (OR = 2.69, p = .008) were associated with increased SLE susceptibility. The rs2248098 G allele and A/G and G/G genotypes were associated to lower SLE susceptibility (OR = 0.66, p = .01; OR = 0.46, p = .01; OR = 0.44, p = .02, respectively). Regarding clinical features, we observed lower risk for: rs11168268 A/G genotype and nephritis (OR = 0.31, p = .01); rs4760648 T/T genotype and photosensitivity (OR = 0.24, p = .02); rs1540339 T/T genotype and antibody anti-dsDNA (OR = 0.19, p = .015); rs3890733 T/T genotype and serositis (OR = 0.10, p = .01). We identified a significant downregulation in VDR expression levels when compared patients and controls overall (p = 1.04e^-7 ), in Cdx-2 A/G and G/G (p = .008 and p = .014, respectively) and in patients with nephritis (p = .016) Our results suggested that VDR SNPs influence upon SLE susceptibility and in particular clinical features, acting on mRNA expression in SLE patients overall and the ones with nephritis.

The Immunologic Profile of Vitamin D and Its Role in Different Immune-Mediated Diseases: An Expert Opinion

Historically, vitamin D is recognized as an essential component for the maintenance of the musculoskeletal system. The immunomodulatory role of vitamin D in health and disease has gained much interest in recent years due to the many pathologies that share underlying immunological features where vitamin D has been shown to exert a potential role. Evidence from pre-clinical studies show that vitamin D elicits biological effects on both the innate and adaptive immune systems. Furthermore, in vivo studies have shown that administration of vitamin D can lead to changes in or the development of a range of immune-related diseases. This encourages the hypothesis that data derived from clinical and epidemiological studies connect vitamin D with the incidence and severity of many immune-mediated disorders such as rheumatoid arthritis, diabetes, and infectious diseases. Since some other immune-mediated diseases share similar features to that of viral infection such as COVID-19, in this review, we examined these other areas and the role of vitamin D in these diseases.

Association of High Calcitriol Serum Levels and Its Hydroxylation Efficiency Ratio with Disease Risk in SLE Patients with Vitamin D Deficiency

Vitamin D (calcidiol) deficiency in systemic lupus erythematosus (SLE) is more frequent than in healthy subjects (HS); it is associated with clinical activity and damage in SLE. Although calcidiol is considered the best indicator of the vitamin D serum status, its deficiency could not reflect its hydroxylation efficiency ratio and calcitriol serum status. This study was aimed at assessing the association of calcidiol and calcitriol serum levels and its hydroxylation efficiency ratio with the risk to clinical and renal disease activities in SLE patients. A cross-sectional study was conducted in 308 SLE and HS women; calcidiol and calcitriol serum levels were evaluated by immunoassays. SLE patients showed lower calcidiol serum levels vs. HS (21.2 vs. 24.2 ng/mL; p < 0.001). Active SLE patients presented higher calcidiol/calcitriol ratio scores vs. inactive SLE patients (2.78 vs. 1.92 pg/ng; p = 0.02), and SLE patients with renal disease activity showed a pattern of calcidiol-deficient levels (19.5 vs. 25.3 ng/mL; p < 0.04) with higher calcitriol levels (47 pg/mL vs. 41.5 pg/mL; p = 0.02) and calcidiol/calcitriol ratio scores (2.13 vs. 1.54 pg/ng; p < 0.02) compared to SLE patients without renal disease activity. Calcidiol levels were negatively correlated with calcitriol levels (r = −0.26; p = 0.001) and urine proteins (mg/dL) (r = −0.39; p < 0.01). Regarding calcitriol levels, it was positively correlated with the blood lymphocyte count (r = 0.30; p < 0.001) and negatively correlated with the glomerular filtration rate (r = −0.28; p = 0.001). Moreover, the calcitriol/calcidiol ratio was positively correlated with urine proteins (r = 0.38; p < 0.01). The calcidiol deficiency (OR = 2.27; 95% CI = 1.15-4.49; p < 0.01), high calcitriol levels (T3^rd, OR = 4.19, 95% CI = 2.23-7.90; p < 0.001), and a high calcitriol/calcidiol ratio score (T3^rd, OR = 5.93, 95% CI: 3.08-11.5; p < 0.001) were associated with the risk for SLE. In conclusion, a pattern of calcidiol deficiency with high calcitriol serum levels and a high vitamin D hydroxylation efficiency ratio was associated with disease risk in SLE patients.

Serum Vitamin D as a Biomarker in Autoimmune, Psychiatric and Neurodegenerative Diseases

Vitamin D is a steroid hormone regulating calcium-phosphorus homeostasis, immune response and brain function. In the past thirty years, an increasing number of cohort studies, meta-analyses and randomized controlled trials (RTCs) evaluated the serum levels of 25-hydroxyvitamin D [25(OH)D], which is considered the Vitamin D status biomarker, in patients affected by neurological, psychiatric and autoimmune diseases. Although an association between low 25(OH)D serum levels and the prevalence of these diseases has been found, it is still unclear whether the serum 25(OH)D measurement can be clinically useful as a biomarker for diagnosis, prognosis and predicting treatment response in neurodegeneration, mental illness and immune-mediated disorders. The lack of standardized data, as well as discrepancies among the studies (in the analytical methods, cut-offs, endpoints and study sets), weakened the findings achieved, hindered pooling data, and, consequently, hampered drawing conclusions. This narrative review summarizes the main findings from the studies performed on serum 25(OH)D in neurological, psychiatric and autoimmune diseases, and clarifies whether or not serum 25(OH)D can be used as a reliable biomarker in these diseases.

Nutrition and connective tissue disease

Despite an incomplete overall understanding, nutrition plays an important role in connective tissue disease. Assessment of patients with connective tissue disease for nutritional status and metabolic disturbances may significantly contribute to patient outcomes. Several studies have indicated the multifactorial role of macronutrients, micronutrients, and supplements in the setting of connective tissue disease. There is additional evidence regarding the roles of weight, obesity, and malnutrition. This contribution reviews a growing body of data regarding nutrition in the development and treatment of various connective tissue diseases, including systemic lupus erythematosus, dermatomyositis, and systemic sclerosis.

Vitamin D Levels are Associated with Disease Activity and Damage Accrual in Systemic Lupus Erythematosus Patients

Vitamin D has immunosuppressive properties and is considered a therapeutic option, although there is controversy about the role of this vitamin in the pathogenesis of systemic lupus erythematosus (SLE). We aimed to determine the prevalence of vitamin D insufficiency and deficiency and their potential association with disease activity, damage accrual, SLE-related clinical manifestations, and cardiovascular risk factors in SLE patients. A cross-sectional study of 264 patients was conducted (89.4% females; mean age 46.7 ± 12.9 years). The SLE Disease Activity Index (SLEDAI-2 K) and the SDI Damage Index were used to assess disease activity and disease-related damage, respectively. The mean 25(OH)D value was 25.1 ± 13.0 ng/ml. Eleven patients (4.2%) had 25(OH)D <10 (deficiency) and 178 patients (70.6%) had 25(OH)D <30 (insufficiency). In the 25(OH)D deficiency group, SLEDAI was significantly higher than the insufficiency (p = 0.001) and normal groups (p < 0.001). Also, patients with vitamin D deficiency presented significantly higher SDI scores than patients with 25(OH)D insufficiency (p = 0.033) and 25(OH)D normal levels (p = 0.029). There is a high prevalence of both vitamin D deficiency and insufficiency in Caucasian SLE patients and this status was associated with higher SLEDAI and SDI scores, supporting the impact of vitamin D levels on disease activity and damage accrual in SLE patients. Longitudinal studies on the relationship between vitamin D status and disease activity and progression are therefore required.

Serum vitamin D level is related to disease progression in primary biliary cholangitis

BACKGROUND AND AIM

A nonskeletal role of vitamin D in primary biliary cholangitis (PBC) patients is not yet clear. The purpose of this study is to investigate the serum vitamin D level in patients with PBC and to explore whether serum vitamin D level is related to disease progression.

METHODS

The serum levels of 25(OH)D₃ were measured in 185 PBC patients and 141 healthy controls. The association with vitamin D levels and disease progression, particularly natural course, was assessed.

RESULTS

Serum vitamin D levels were measured in 185 patients with PBC. The mean level of vitamin D in advanced stage patients was lower than that in early stage patients (9.15 ± 5.33 ng/ml vs. 13.68 ± 6.33 ng/ml, p = .000). In the follow-up patients, the vitamin D level in the taken calcitriol patients showed an upward trend, while the un-taken calcitriol patients was opposite. Besides, vitamin D levels were correlated with the changes of bilirubin, albumin (ALB) and APRI (p<.05). PBC patients with vitamin D deficiency had higher bilirubin levels and lower ALB levels (p<.05). Moreover, there were differences in serum vitamin D levels between taken calcitriol patients and un-taken calcitriol patients (p = .027).

CONCLUSIONS

Vitamin D deficiency is highly prevalent in PBC patients. The decrease of vitamin D levels may indicate disease progression in PBC. PBC patients need to be regularly measured for serum vitamin D level and take appropriate vitamin D supplementation.

Immunomodulatory Effects of Diet and Nutrients in Systemic Lupus Erythematosus (SLE): A Systematic Review

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by multiple organ involvement, including the skin, joints, kidneys, lungs, central nervous system and the haematopoietic system, with a large number of complications. Despite years of study, the etiology of SLE remains unclear; thus, safe and specifically targeted therapies are lacking. In the last 20 years, researchers have explored the potential of nutritional factors on SLE and have suggested complementary treatment options through diet. This study systematically reviews and evaluates the clinical and preclinical scientific evidence of diet and dietary supplementation that either alleviate or exacerbate the symptoms of SLE. For this review, a systematic literature search was conducted using PubMed, Scopus and Google Scholar databases only for articles written in the English language. Based on the currently published literature, it was observed that a low-calorie and low-protein diet with high contents of fiber, polyunsaturated fatty acids, vitamins, minerals and polyphenols contain sufficient potential macronutrients and micronutrients to regulate the activity of the overall disease by modulating the inflammation and immune functions of SLE.

Vitamin D in Colombian patients with systemic lupus erythematosus and its correlation with disease activity

Introduction

Patients with systemic lupus erythematosus (SLE) frequently present low levels of vitamin D. However, studies that have evaluated its association with disease activity have generated contradictory results.

Methods

A cross-sectional study was carried out on patients diagnosed with SLE in two hospitals in Manizales, Colombia. Disease activity was evaluated by the SLE disease activity index 2000 (SLEDAI-2K) and serum concentration of 25-hydroxyvitamin D (25(OH)D) was measured by chemiluminescence. The correlation analysis was accomplished with the Spearman correlation coefficient.

Results

The study included 51 patients. The median SLEDAI-2K score was 8 points. The mean serum level of 25(OH)D was 24.5 ng/ml. Of the participants, 37.3% had vitamin D insufficiency and 35.3% had deficiency. An inverse correlation was found between the levels of the 25(OH)D and the SLEDAI-2K score ( r = –0.578, p < 0.001), being greater in late-onset lupus, with absence of polyautoimmunity and in patients using glucocorticoids.

Conclusions

Low levels of vitamin D are frequent in SLE, presenting an inverse correlation with the disease activity. This is influenced by the use of glucocorticoids, the presence of late-onset lupus and the absence of polyautoimmunity.

Bioavailable 25(OH)D level is associated with clinical outcomes of patients with diffuse large B-cell lymphoma: An exploratory study

BACKGROUNDS & AIMS

Vitamin D insufficiency is associated with worse clinical outcomes in multiple cancer types; however, its roles in diffuse large B-cell lymphoma (DLBCL) patients are still unclear. Here, we aimed to determine the prognostic values of circulating total 25(OH)D and bioavailable 25(OH)D levels in DLBCL patients.

METHODS

A total of 332 newly diagnosed DLBCL patients were recruited. The plasma total 25(OH)D and bioavailable 25(OH)D levels at diagnosis were determined, and their associations with the clinical characteristics and the prognosis of patients were evaluated. The predictive values of clinical characteristics and 25(OH)D levels in the responses to R-CHOP treatments in DLBCL patients were also assessed.

RESULTS

Of the patients, 92.8% had insufficient vitamin D status (<30 ng/mL). Patients with higher plasma bioavailable 25(OH)D were associated with better progression-free survival (PFS, multivariate adjusted-HR = 0.72, 95% CI = 0.38-1.35, P = 0.301, Tertile 2 vs. 1; multivariate adjusted-HR = 0.39, 95% CI = 0.20-0.79, P = 0.009, Tertile 3 vs. 1) and overall survival (OS, multivariate adjusted-HR = 0.89, 95% CI = 0.39-2.02, P = 0.777, Tertile 2 vs. 1; multivariate adjusted-HR = 0.21, 95% CI = 0.07-0.65, P = 0.007, Tertile 3 vs. 1). Meanwhile, higher plasma total 25(OH)D level was significantly associated with better PFS but not OS in DLBCL patients. Besides, DLBCL patients with higher total or bioavailable 25(OH)D levels were more sensitive to the R-CHOP regimen treatments.

CONCLUSION

The bioavailable 25(OH)D level may serve as a novel prognostic biomarker in DLBCL patients.

Vitamin D status in patients with systemic lupus erythematosus (SLE): A systematic review and meta-analysis

BACKGROUND

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease where chronic inflammation and tissue or organ damage is observed. Due to various suspected causes, inadequate levels of vitamin D (a steroid hormone with immunomodulatory effects) has been reported in patients with SLE, however, contradictory.

AIMS

The aim of this systematic review and meta-analysis was to evaluate the serum levels of vitamin D in patients with SLE in compared to healthy controls.

METHODS

PubMed, SCOPUS, ScienceDirect and Google Scholar electronic databases were searched systematically without restricting the languages and year (up to March 2, 2019) and studies were selected based on the inclusion criteria. Mean difference (MD) along with 95% confidence intervals (CI) were used and the analyses were carried out by using a random-effects model. Different subgroup and sensitivity analyses were conducted. Study quality was assessed by the modified Newcastle-Ottawa Scale (NOS) and publication bias was evaluated by a contour-enhanced funnel plot, Begg's and Egger's tests.

RESULTS

We included 34 case-control studies (2265 SLE patients and 1846 healthy controls) based on the inclusion criteria. Serum levels of vitamin D was detected significantly lower in the SLE patients than that in the healthy controls (MD: -10.44, 95% CI: -13.85 to -7.03; p < .00001). SLE patients from Asia (MD: -13.75, 95% CI: -21.45 to -6.05; p = .0005), South America (MD: -3.16, 95% CI: -4.62 to -1.70; p < .0001) and Africa (MD: -16.15, 95% CI: -23.73 to -8.56; p < .0001); patients residing below 37° latitude (MD: -11.75, 95% CI: -15.79 to -7.70; p < .00001); serum vitamin D during summer season (MD: -7.89, 95% CI: -11.70 to -4.09; p < .0001), patients without vitamin D supplementation (MD: -15.57, 95% CI: -19.99 to -11.14; p < .00001) or on medications like hydroxychloroquine, corticosteroids or immunosuppressants without vitamin D supplementation (MD: -16.46, 95% CI: -23.86 to -9.05; p < .0001) are in higher risk in presenting inadequate serum levels of vitamin D. The results remained statistically significant from different sensitivity analyses which represented the robustness of this meta-analysis. According to the NOS, 91.2% of the studies were considered as of high methodological quality (low risk of bias). No significant publication bias was detected from contour-enhanced and trim and fill funnel plots or Begg's test.

CONCLUSION

Inadequate levels of serum vitamin D is significantly high in patients with SLE compared to healthy subjects, therefore, vitamin D supplementation with regular monitoring should be considered as part of their health management plans.

Emerging role of vitamin D in autoimmune diseases: An update on evidence and therapeutic implications

Vitamin D plays a key role in in calcium homeostasis and, thus, provides an important support in bone growth by aiding in the mineralization of the collagen matrix. However, vitamin D performs various immunomodulatory, anti-inflammatory, antioxidant and anti-fibrotic actions. Autoimmune diseases result from an aberrant activation of the immune system, whereby the immune response is directed against harmless self-antigens. Does vitamin D play a role in the pathophysiology of autoimmune diseases? And, if so, what is its role? In the last decade, researchers' interest in vitamin D and its correlations with autoimmune diseases has considerably increased. We conducted a literature review, covering the period January 1, 2009 through March 30, 2019, in PubMed. We analyzed more than 130 studies in order to find a correlation between vitamin D levels and its effect upon several autoimmune diseases. The analysis demonstrated an inverse association between vitamin D and the development of several autoimmune diseases, such as SLE, thyrotoxicosis, type 1 DM, MS, iridocyclitis, Crohn's disease, ulcerative colitis, psoriasis vulgaris, seropositive RA, polymyalgia rheumatica. International multicenter study could allow us to confirm the data already present in the literature in the single clinical studies and to evaluate when to effectively supplement vitamin D in patients who do not take corticosteroids.

Vitamin D and the Skin: A Review for Dermatologists

In recent years, the growing interest in the role played by vitamin D in skin disease has given rise to the publication of many studies of the relationship between this vitamin and certain skin conditions. As dermatologists, we need to understand, among other aspects, how vitamin D is synthesized and the main sources in humans, as well as plasma levels and the factors that can modify them. Of particular interest are the latest discoveries about the role of vitamin D in skin diseases such as lupus erythematosus, ichthyosis, atopic dermatitis, hidradenitis suppurativa, acne, alopecia areata, androgenetic alopecia, melanoma, and nonmelanoma skin cancer. Also of interest is the importance of vitamin D as adjuvant therapy in patients on long-term treatment with corticosteroids. In this review, we provide an overview of the most important and most recent information regarding the relationship between vitamin D and skin disease and discuss the importance of assessing individual vitamin D status and correcting deficiencies.

A subgroup of lupus patients with nephritis, innate T cell activation and low vitamin D is identified by the enhancement of circulating MHC class I-related chain A

The major histocompatibility complex (MHC) class I-related chain A (MICA) is induced upon stress, and labels malfunctioning cells for their recognition by cytotoxic lymphocytes. Alterations in this recognition and also abnormal natural killer (NK) functions have been found in systemic lupus erythematosus (SLE). MICA can be shed from cells, subsequently acting as a soluble decoy receptor (sMICA). Our purpose was to study circulating sMICA levels in relationship with the activation of innate pathways in PBMC in a cohort of lupus patients. NK cells were characterized by flow cytometry. Gene expression of Toll-like receptors (TLR), interferon (IFN)-I sensitive genes and MICA were separately analyzed in monocytes, T cells and B cells. Serum sMICA was measured with enzyme-linked immunosorbent assay (ELISA). In our cohort, NK cell counts dropped in relationship with disease activity. sMICA showed an inverse trend with NK cell counts, as well as a significant association with activity indices, but not with complement decrease. Levels of sMICA associated to proteinuria and active nephritis. A multivariate regression model revealed anti-nuclear antibody (ANA) titres, the up-regulation of TLR-4 in T cells and lower vitamin D as predictors of sMICA enhancement. Interestingly, vitamin D showed an inverse association with proteinuria and a strong correlation with T cell MICA mRNA levels. According to our data, circulating sMICA identifies a subgroup of lupus patients with low vitamin D, innate activation of T cells and nephritis. We propose that lymphocyte shedding could account for the enhancement of sMICA and reflect an immune evasion mechanism driving disease activation in lupus.

Evolving Role of Vitamin D in Immune-Mediated Disease and Its Implications in Autoimmune Hepatitis

Vitamin D has immunomodulatory, anti-inflammatory, antioxidant, and anti-fibrotic actions that may impact on the occurrence and outcome of immune-mediated disease. The goals of this review are to describe the nature of these expanded roles, examine the implications of vitamin D deficiency in autoimmune hepatitis, and identify opportunities for future investigation. Abstracts were identified in PubMed by multiple search terms. Full-length articles were selected for review, and secondary and tertiary bibliographies were developed. Vitamin D receptors are expressed on the principal cell populations involved in the innate and adaptive immune responses. Macrophages and dendritic cells can produce 1,25-dihydroxyvitamin D within the microenvironment. This active form of vitamin D can inhibit immune cell proliferation, promote an anti-inflammatory cytokine profile, expand regulatory T cells, enhance glucocorticoid actions, increase glutathione production, and inhibit hepatic stellate cells. Vitamin D deficiency has been commonly present in patients with immune-mediated liver and non-liver diseases, and it has been associated with histological severity, advanced hepatic fibrosis, and non-response to conventional glucocorticoid therapy in autoimmune hepatitis. Vitamin D analogues with high potency, low calcemic effects, and independence from hepatic hydroxylation are possible interventions. In conclusion, vitamin D has properties that could ameliorate immune-mediated disease, and vitamin D deficiency has been a common finding in immune-mediated liver and non-liver diseases, including autoimmune hepatitis. Loss of vitamin D-dependent homeostatic mechanisms may promote disease progression. Vitamin D analogues that are independent of hepatic hydroxylation constitute an investigational opportunity to supplement current management of autoimmune hepatitis.

The Role of Vitamin D Binding Protein, Total and Free 25-Hydroxyvitamin D in Diabetes

Vitamin D is important for bone health, but may also have extra-skeletal effects. Vitamin D and its binding protein DBP have immunological effects and may therefore be important in the development of type 1 diabetes (T1DM), and low serum levels of 25-hydroxyvitamin D (25(OH)D) are associated with later development of type 2 diabetes (T2DM). However, it has so far been difficult to convincingly show an effect of vitamin D supplementation on prevention or treatment of diabetes. The serum level of 25(OH)D has traditionally been used as a marker of a subject's vitamin D status. This measurement includes both 25(OH)D bound to DBP and albumin as well as the free from of 25(OH)D. However, according to the free hormone hypothesis, the free form is the biologically active. Previously the free form of 25(OH)D had to be calculated based on measurements of 25(OH)D, DBP, and albumin, but recently a method for direct measurement of free 25(OH)D has become commercially available. This is important in clinical conditions where the amount of DBP is affected, and has caused a renewed interest in which vitamin D metabolite to measure in clinical situations. In the present review the relations between DBP, total and free 25(OH)D in T1DM and T2DM are described.

To Supplement or not to Supplement? The Rationale of Vitamin D Supplementation in Systemic Lupus Erythematosus

Background:

Systemic Lupus Erythematosus (SLE) is a systemic autoimmune disease characterised by abnormal activation of the immune system, chronic inflammation and organ damage. Lupus patients are more prone to be vitamin D deficient. However, current evidence is not conclusive with regards to the role played by vitamin D in SLE development, progression, and clinical manifestations.

Objective:

Here, we will summarise the current knowledge about vitamin D deficiency prevalence, risk factors, molecular effects, and potential pathogenic role in SLE. We will focus on the link between vitamin D deficiency and lupus clinical manifestations, and on the clinical trials assessing the effects of vitamin D supplementation in SLE.

Method:

A detailed literature search was performed exploiting the available databases, using “vitamin D and lupus/SLE” as keywords. The relevant interventional trials published over the last decade have been considered and the results are reported here.

Conclusion:

Several immune cells express vitamin D receptors. Thus, an immunomodulatory role for vitamin D in lupus is plausible. Numerous observational studies have investigated the relationship between vitamin D levels and clinical/serological manifestations of SLE with contrasting results. Negative correlations between vitamin D levels and disease activity, fatigue, renal and cardiovascular disease, and anti-dsDNA titres have been described but not conclusively accepted. In experimental models of lupus, vitamin D supplementation can improve the disease. Interventional trials have assessed the potential therapeutic value of vitamin D in SLE, but further larger studies are needed.

The Impact of Vitamin D on the Immunopathophysiology, Disease Activity, and Extra-Musculoskeletal Manifestations of Systemic Lupus Erythematosus

Over the past two decades it has been increasingly recognized that vitamin D, aside from its crucial involvement in calcium and phosphate homeostasis and the dynamics of the musculoskeletal system, exerts its influential impact on the immune system. The mechanistic roles that vitamin D plays regarding immune activation for combating infection, as well as pathologically and mediating autoimmune conditions, have been progressively unraveled. In vitro and in vivo models have demonstrated that the action of vitamin D on various immunocytes is not unidirectional. Rather, how vitamin D affects immunocyte functions depends on the context of the immune response, in the way that its suppressive or stimulatory action offers physiologically appropriate and immunologically advantageous outcomes. In this review, the relationship between various aspects of vitamin D, starting from its adequacy in circulation to its immunological functions, as well as its autoimmune conditions, in particular systemic lupus erythematosus (SLE), a prototype autoimmune condition characterized by immune-complex mediated inflammation, will be discussed. Concurring with other groups of investigators, our group found that vitamin D deficiency is highly prevalent in patients with SLE. Furthermore, the circulating vitamin D levels appear to be correlated with a higher disease activity of SLE as well as extra-musculoskeletal complications of SLE such as fatigue, cardiovascular risk, and cognitive impairment.

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.

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.

Vitamin D Supplementation Guidelines for General Population and Groups at Risk of Vitamin D Deficiency in Poland-Recommendations of the Polish Society of Pediatric Endocrinology and Diabetes and the Expert Panel With Participation of National Specialist Consultants and Representatives of Scientific Societies-2018 Update

INTRODUCTION

Vitamin D deficiency is an important public health problem worldwide. Vitamin D deficiency confers a significant risk for both skeletal and non-skeletal disorders and a number of lifelong negative health outcomes. The objectives of this evidence-based guidelines document are to provide health care professionals in Poland, an updated recommendation for the prevention, diagnosis and treatment of vitamin D deficiency.

METHODS

A systematic literature search examining the prevention and treatment strategies for vitamin D deficiency was conducted. Updated recommendations were developed using the Grading of Recommendations, Assessment, Development and Evaluation system describing the strength of the recommendation and the quality of supporting evidence. Twenty-seven contributors representing different areas of expertise and medical specialties, including pediatricians, geriatricians, endocrinologists, epidemiologists, nephrologists, gynecologists and obstetricians evaluated the available published evidence related to vitamin D, formulated the goals of this document and developed a common consolidated position. The consensus group, representing six national specialist consultants and eight Polish and international scientific organizations/societies, participated in the process of grading evidence and drawing up the general and specific recommendations.

RESULTS

The updated recommendations define the diagnostic criteria for the evaluation of vitamin D status and describe the prevention and treatment strategies of vitamin D deficiency in the general population and in groups at increased risk of the deficiency. Age- and weight-specific recommendations for prevention, supplementation and treatment of vitamin D deficiency are presented, and detailed practice guidance is discussed regarding the management in primary and specialized health care.

CONCLUSION

Vitamin D deficiency remains still highly prevalent in Poland, in all age groups. Currently, there is a great necessity to implement a regular supplementation with recommended doses and to develop an effective strategy to alleviate vitamin D deficiency in the population. These updated recommendations are addressed to health professionals and the authorities pursuing comprehensive health policies and should also be included in public health programs aimed at preventing a broad spectrum of chronic diseases.

Vitamin D supplementation and disease activity in patients with immune-mediated rheumatic diseases: A systematic review and meta-analysis

BACKGROUND

Vitamin D serum levels and the presence and activity of rheumatic conditions have been associated. However, many studies are merely observational, and the existent randomized clinical trials were never systematically analyzed. Therefore, this study aims to provide a systematic review and meta-analysis of such a topic.

METHODS

MEDLINE, EMBASE, LILACS, COCHRANE, and CINAHL were explored to identify randomized trials that investigated clinical repercussions of vitamin D (or analogs) supplementation for at least 3 months in rheumatic diseases. Standardized clinical and/or laboratorial outcomes related to disease activity were analyzed according to each disease before and after supplementation.

RESULTS

Database searches rendered 668 results; 9 were included-5 on rheumatoid arthritis, 3 on systemic lupus erythematosus, and 1 on systemic sclerosis. Seven of the studies were meta-analyzed. After vitamin D supplementation, rheumatoid arthritis recurrence decreased; however, not significantly (risk difference = -0.10, 95% CI = -0.21, 0.00, P = .05). No statistical significance was observed regarding visual analog scale (mean difference = 2.79, 95% CI = -1.87, 7.44, P = .24) and disease activity score28 (mean difference = -0.31, 95% CI = -0.86, 0.25, P = .28). Regarding systemic lupus erythematosus, anti-dsDNA positivity was significantly reduced (risk difference = -0.10, 95% CI = -0.18, -0.03; P = .005).

CONCLUSION

Vitamin D supplementation reduced anti-dsDNA positivity on systemic lupus erythematosus and could possibly reduce rheumatoid arthritis recurrence, although novel randomized clinical trials are needed to confirm and extend the benefits of this hormone in immune-mediated rheumatic diseases.

Immune Modulation by Vitamin D: Special Emphasis on Its Role in Prevention and Treatment of Cancer

PURPOSE

Vitamin D has been known to be involved in mineral and bone homeostasis for many years. In the past its main use was in treating osteoporosis and rickets. In recent years it was found that vitamin D is an immune-modulating agent and may also have a role in several diseases, including autoimmune diseases. The immune-modulating effects appear to be mediated by vitamin D interaction with the vitamin D receptor (VDR) that has transcriptional effects and is expressed on various cell types, especially those of the immune system. Immunologic and rheumatologic diseases were the first to be studied, but at the moment the spotlight is on the interactions between tumor cells and vitamin D. This review focuses on four forms of cancer that apparently benefit from a vitamin D supplementation during treatment: prostate, breast, and colorectal cancers and melanoma. Several studies reported that differences exist between white and black patients, which we discuss in the review.

METHODS

We systematically searched PubMed for studies published in English. The search terms included vitamin D, cancer, breast, colorectal, prostate, and melanoma.

FINDINGS AND IMPLICATIONS

Our findings show that vitamin D has the potential to become a valid coadjuvant in the treatment of cancer.