Evidence that abnormally large seasonal declines in vitamin D status may trigger SLE flare in non-African Americans

Infections and Autoimmunity-The Immune System and Vitamin D: A Systematic Review

Both 25-autoimmunity and(25(OH)D: calcifediol) and its active form, 1,25-dihydroxyvitamin D (1,25(OH)2D: calcitriol), play critical roles in protecting humans from invasive pathogens, reducing risks of autoimmunity, and maintaining health. Conversely, low 25(OH)D status increases susceptibility to infections and developing autoimmunity. This systematic review examines vitamin D's mechanisms and effects on enhancing innate and acquired immunity against microbes and preventing autoimmunity. The study evaluated the quality of evidence regarding biology, physiology, and aspects of human health on vitamin D related to infections and autoimmunity in peer-reviewed journal articles published in English. The search and analyses followed PRISMA guidelines. Data strongly suggested that maintaining serum 25(OH)D concentrations of more than 50 ng/mL is associated with significant risk reduction from viral and bacterial infections, sepsis, and autoimmunity. Most adequately powered, well-designed, randomized controlled trials with sufficient duration supported substantial benefits of vitamin D. Virtually all studies that failed to conclude benefits or were ambiguous had major study design errors. Treatment of vitamin D deficiency costs less than 0.01% of the cost of investigation of worsening comorbidities associated with hypovitaminosis D. Despite cost-benefits, the prevalence of vitamin D deficiency remains high worldwide. This was clear among those who died from COVID-19 in 2020/21-most had severe vitamin D deficiency. Yet, the lack of direction from health agencies and insurance companies on using vitamin D as an adjunct therapy is astonishing. Data confirmed that keeping an individual's serum 25(OH)D concentrations above 50 ng/mL (125 nmol/L) (and above 40 ng/mL in the population) reduces risks from community outbreaks, sepsis, and autoimmune disorders. Maintaining such concentrations in 97.5% of people is achievable through daily safe sun exposure (except in countries far from the equator during winter) or taking between 5000 and 8000 IU vitamin D supplements daily (average dose, for non-obese adults, ~70 to 90 IU/kg body weight). Those with gastrointestinal malabsorption, obesity, or on medications that increase the catabolism of vitamin D and a few other specific disorders require much higher intake. This systematic review evaluates non-classical actions of vitamin D, with particular emphasis on infection and autoimmunity related to the immune system.

Involvement of the secosteroid vitamin D in autoimmune rheumatic diseases and COVID-19

Evidence supporting the extra-skeletal role of vitamin D in modulating immune responses is centred on the effects of its final metabolite, 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃, also known as calcitriol), which is regarded as a true steroid hormone. 1,25(OH)₂D₃, the active form of vitamin D, can modulate the innate immune system in response to invading pathogens, downregulate inflammatory responses and support the adaptive arm of the immune system. Serum concentrations of its inactive precursor 25-hydroxyvitamin D₃ (25(OH)D₃, also known as calcidiol) fluctuate seasonally (being lowest in winter) and correlate negatively with the activation of the immune system as well as with the incidence and severity of autoimmune rheumatic diseases such as rheumatoid arthritis, systemic lupus erythematosus and systemic sclerosis. Thus, a low serum concentration of 25(OH)D₃ is considered to be a risk factor for autoimmune rheumatic diseases and vitamin D₃ supplementation seems to improve the prognosis; moreover, long-term vitamin D₃ supplementation seems to reduce their incidence (i.e. rheumatoid arthritis). In the setting of COVID-19, 1,25(OH)₂D₃ seems to downregulate the early viral phase (SARS-CoV-2 infection), by enhancing innate antiviral effector mechanisms, as well as the later cytokine-mediated hyperinflammatory phase. This Review provides an update of the latest scientific and clinical evidence concerning vitamin D and immune response in autoimmune rheumatic diseases and COVID-19, which justify the need for monitoring of serum 25(OH)D₃ concentrations and for appropriate supplementation following clinical trial-based approaches.

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.

High Prevalence of Hypovitaminosis D in Cutaneous and Systemic Lupus Erythematosus Patients and Its Associated Factors: A Cross-Sectional Study in Thailand

Objective

To investigate the prevalence of low vitamin D levels in patients with cutaneous lupus erythematosus (CLE) and systemic lupus erythematosus (SLE) in Thailand and determine the influential factors associated with inadequate levels.

Methods

The medical records of patients diagnosed with SLE and/or CLE and evaluated for serum 25-OH vitamin D were retrospectively reviewed from January 2014 to January 2021. Vitamin D deficiency (<20 ng/mL) and insufficiency (21-29 ng/mL) were indicated, and predictors of hypovitaminosis D were identified by multiple linear regression analysis.

Results

In total, 414 patients with SLE and/or CLE were included in the study. Vitamin D deficiency was predominant in the CLE-only group (33.3%), followed by SLE without CLE (15.6%) and SLE with CLE (8%), p < 0.001. Likewise, vitamin D insufficiency was more prevalent in the CLE-only group (44.4%) compared to SLE with (35.8%) and without CLE (40%). Multivariate analysis showed that a higher SLEDAI-2K score and female sex had a negative association with vitamin D levels, while an intake of every 10,000 IU of vitamin D2 per week increased serum vitamin D levels by up to 2.37 ng/mL. Furthermore, forty-five percent of patients continued to have vitamin D depletion despite commencing the recommended doses of vitamin D replacement.

Conclusion

Approximately half of Thai patients with SLE and 80% of CLE had vitamin D inadequacy. Vitamin D replacement is a good predictor of high serum vitamin D levels, while lower serum levels were associated with higher disease severity. Therefore, serum vitamin D monitoring and supplementation are suggested for all lupus erythematosus cases, especially those with CLE.

The Influence of an Elastase-Sensitive Complement C5 Variant on Lupus Nephritis and Its Flare

Introduction

A C5 polymorphism (rs17611, 2404G>A) exists where the G allele associates with enhanced C5a-like production by neutrophil elastase. This cohort study investigated the influence of this polymorphism as a risk factor for lupus nephritis (LN), and on C5a and membrane attack complex (MAC) levels in LN during flare.

Methods

A cohort of lupus patients (n = 155) was genotyped for the 2404G>A polymorphism. A longitudinal LN subset (n = 66) was tested for plasma and urine levels of C5a and MAC 4 and/or 2 months before and at nonrenal or LN flare.

Results

The 2404G allele and 2404-GG genotype were associated with LN in black, but not white, lupus patients. In the longitudinal cohort, neither urine nor plasma C5a levels changed at nonrenal flare regardless of 2404G>A genotype or race. Urine (but not plasma) C5a levels increased at LN flare independent of race, more so in 2404-GG patients where 8 of 30 LN flares exhibited very high C5a levels. Higher proteinuria and serum creatinine levels also occurred in these eight flares. Urine (but not plasma) MAC levels also increased at LN flare in 2404-GG patients and correlated with urine C5a levels.

Conclusions

The C5 2404-G allele/GG genotype is a potential risk factor for LN uniquely in black lupus patients. The GG genotype is associated with sharp increases in urine C5a and MAC levels in a subset of LN flares that correspond to higher LN disease indices. The lack of corresponding changes in plasma suggests these increases reflect intrarenal complement activation.

Patients with Proliferative Lupus Nephritis Have Autoantibodies That React to Moesin and Demonstrate Increased Glomerular Moesin Expression

Kidney involvement in systemic lupus erythematosus (SLE)—termed lupus nephritis (LN)—is a severe manifestation of SLE that can lead to end-stage kidney disease (ESKD). LN is characterized by immune complex deposition and inflammation in the glomerulus. We tested the hypothesis that autoantibodies targeting podocyte and glomerular cell proteins contribute to the development of immune complex formation in LN. We used Western blotting with SLE sera from patients with and without LN to identify target antigens in human glomerular and cultured human-derived podocyte membrane proteins. Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), we identified the proteins in the gel regions corresponding to reactive bands observed with sera from LN patients. We identified 102 proteins that were present in both the podocyte and glomerular samples. We identified 10 high-probability candidates, including moesin, using bioinformatic analysis. Confirmation of moesin as a target antigen was conducted using immunohistochemical analysis (IHC) of kidney biopsy tissue and enzyme-linked immunosorbent assay (ELISA) to detect circulating antibodies. By IHC, biopsies from patients with proliferative lupus nephritis (PLN, class III/IV) demonstrated significantly increased glomerular expression of moesin (p < 0.01). By ELISA, patients with proliferative LN demonstrated significantly increased antibodies against moesin (p < 0.01). This suggests that moesin is a target glomerular antigen in lupus nephritis.

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.

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.

Efficacy and Safety of Vitamin D Supplementation in Patients With Systemic Lupus Erythematosus: A Meta-analysis of Randomized Controlled Trials

BACKGROUND

The efficacy of vitamin D supplementation in patients with systemic lupus erythematosus (SLE) remains uncertain. This meta-analysis aimed to systematically evaluate the efficacy and safety of vitamin D supplementation in patients with SLE.

MATERIALS AND METHODS

Randomized controlled trials (RCTs) were searched in PubMed, Embase, Cochrane CENTRAL and Web of Science databases. The retrieved studies were subjected to meta-analysis using the fixed-effect or random-effect model.

RESULTS

Five eligible RCTs enrolling 490 participants were included. Compared to the placebo treatment, vitamin D supplementation significantly increased the level of serum 25-hydroxyvitamin D (25(OH)D) (5 trials, 490 participants: standard mean difference (SMD) = 2.072, 95% CI: 1.078-3.066, P < 0.001). The pooled result from 2 RCTs showed that vitamin D supplementation decreased the fatigue severity scale scores in patients with SLE (2 trials, 79 participants: SMD = -1.179, 95% CI: -1.897 to -0.460, P = 0.001). The SLE disease activity index scores and positivity of anti-double-stranded DNA antibodies (anti-dsDNA) did not differ significantly (4 trials, 223 participants: SMD = -0.507, 95% CI: -1.055-0.041, P = 0.070; 3 trials, 361 participants: Risk ratio = 0.880, 95% CI: 0.734-1.054, P = 0.165) between the vitamin D supplementation group and the placebo treatment group. None of the included studies reported severe adverse events associated with vitamin D supplementation.

CONCLUSIONS

This meta-analysis suggested that vitamin D supplementation is effective in increasing the serum 25(OH)D levels, may improve fatigue, and is well-tolerated in patients with SLE, however, it does not seem to have significant effects in decreasing the positivity of anti-dsDNA and disease activity.

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.

Serum 25-hydroxyvitamin D3 levels and flares of systemic lupus erythematosus: a longitudinal cohort analysis

The aim of this study is to evaluate the relationship between baseline serum 25-hydroxyvitamin D3 levels and SLE activity/flares over time. This is a longitudinal study of 276 patients who fulfilled ≥ 4 ACR criteria for SLE and recruited in the year 2011. Serum samples were collected at baseline and assayed for 25-hydroxyvitamin D3 at the end of a mean follow-up of 32.5 months. Participants were stratified into three groups according to baseline 25-hydroxyvitamin D3 levels: group I (< 15 ng/ml, deficiency), group II (15-30 ng/ml, insufficiency), and group III (> 30 ng/ml, adequate). Baseline and summated SLE disease activity index (SLEDAI) score over time and the annual incidence of lupus flares were compared among these groups. 25-hydroxyvitamin D3 levels of < 15, 15-30, and > 30 ng/ml were present in 26, 54, and 20% of the recruited patients, respectively. Group I had significantly higher baseline SLEDAI scores. After a follow-up of 32.5 ± 5.5 months, 153 mild/moderate and 91 severe flares developed. The mean summated SLEDAI was 3.2 ± 2.0 in group I, 2.4 ± 1.9 in group II and 2.7 ± 2.1 in group III patients (P = 0.02). The annual incidence of mild/moderate and severe flares was 0.26 ± 0.39 and 0.20 ± 0.45 (group I); 0.20 ± 0.33 and 0.09 ± 0.22 (group II); and 0.20 ± 0.32 and 0.14 ± 0.46 (group III), respectively (P > 0.05). In a subgroup of 73 patients who were clinically and serologically quiescent at baseline, a similar trend of more flares was observed in group I patients. Vitamin D deficiency was frequent in Chinese SLE patients and was associated with more active disease at baseline and over time, as well as a trend of more severe lupus flares.

Topics on vitamin D in systemic lupus erythematosus: analysis of evidence and critical literature review

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with multiorgan inflammation, linked to the loss of immune tolerance to self-antigens and the production of a diversity of autoantibodies. The phenotype and progression of SLE have been linked to a combination of environmental, genetic, and hormonal factors. One such environmental factor is vitamin D, a vital hormone with well-established effects on mineral metabolism, skeletal health, and effects on cardiovascular system. The purpose of this article is to make the analysis of evidence and literature review of the pleomorphic effects of Vitamin D in SLE. The article is structured in topics of interest based in the authors' opinion and summarizes the evidence of studies and trials of vitamin D in SLE.

Raising awareness on the therapeutic role of cholecalciferol in CKD: a multidisciplinary-based opinion

Vitamin D is recognized to play an essential role in health and disease. In kidney disease, vitamin D analogs have gained recognition for their involvement and potential therapeutic importance. Nephrologists are aware of the use of oral native vitamin D supplementation, however, uncertainty still exists with regard to the use of this treatment option in chronic kidney disease as well as clinical settings related to chronic kidney disease, where vitamin D supplementation may be an appropriate therapeutic choice. Two consecutive meetings were held in Florence in July and November 2016 comprising six experts in kidney disease (N = 3) and bone mineral metabolism (N = 3) to discuss a range of unresolved issues related to the use of cholecalciferol in chronic kidney disease. The panel focused on the following six key areas where issues relating to the use of oral vitamin D remain controversial: (1) vitamin D and parathyroid hormone levels in the general population, (2) cholecalciferol in chronic kidney disease, (3) vitamin D in cardiovascular disease, (4) vitamin D and renal bone disease, (5) vitamin D in rheumatological diseases affecting the kidney, (6) vitamin D and kidney transplantation.

Modulation of inflammatory and immune responses by vitamin D

Vitamin D (VitD) is a prohormone most noted for the regulation of calcium and phosphate levels in circulation, and thus of bone metabolism. Inflammatory and immune cells not only convert inactive VitD metabolites into calcitriol, the active form of VitD, but also express the nuclear receptor of VitD that modulates differentiation, activation and proliferation of these cells. In vitro, calcitriol upregulates different anti-inflammatory pathways and downregulates molecules that activate immune and inflammatory cells. Administration of VitD has beneficial effects in a number of experimental models of autoimmune disease. Epidemiologic studies have indicated that VitD insufficiency is frequently associated with immune disorders and infectious diseases, exacerbated by increasing evidence of suboptimal VitD status in populations worldwide. To date, however, most interventional studies in human inflammatory and immune diseases with VitD supplementation have proven to be inconclusive. One of the reasons could be that the main VitD metabolite measured in these studies was the 25-hydroxyVitD (25OHD) rather than its active form calcitriol. Although our knowledge of calcitriol as modulator of immune and inflammatory reactions has dramatically increased in the past decades, further in vivo and clinical studies are needed to confirm the potential benefits of VitD in the control of immune and inflammatory conditions.

Vitamin D supplementation in the prevention and management of major chronic diseases not related to mineral homeostasis in adults: research for evidence and a scientific statement from the European society for clinical and economic aspects of osteoporosis and osteoarthritis (ESCEO)

INTRODUCTION

Optimal vitamin D status promotes skeletal health and is recommended with specific treatment in individuals at high risk for fragility fractures. A growing body of literature has provided indirect and some direct evidence for possible extraskeletal vitamin D-related effects.

PURPOSE AND METHODS

Members of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis have reviewed the main evidence for possible proven benefits of vitamin D supplementation in adults at risk of or with overt chronic extra-skeletal diseases, providing recommendations and guidelines for future studies in this field.

RESULTS AND CONCLUSIONS

Robust mechanistic evidence is available from in vitro studies and in vivo animal studies, usually employing cholecalciferol, calcidiol or calcitriol in pharmacologic rather than physiologic doses. Although many cross-sectional and prospective association studies in humans have shown that low 25-hydroxyvitamin D levels (i.e., <50 nmol/L) are consistently associated with chronic diseases, further strengthened by a dose-response relationship, several meta-analyses of clinical trials have shown contradictory results. Overall, large randomized controlled trials with sufficient doses of vitamin D are missing, and available small to moderate-size trials often included people with baseline levels of serum 25-hydroxyvitamin D levels >50 nmol/L, did not simultaneously assess multiple outcomes, and did not report overall safety (e.g., falls). Thus, no recommendations can be made to date for the use of vitamin D supplementation in general, parental compounds, or non-hypercalcemic vitamin D analogs in the prevention and treatment of extra-skeletal chronic diseases. Moreover, attainment of serum 25-hydroxyvitamin D levels well above the threshold desired for bone health cannot be recommended based on current evidence, since safety has yet to be confirmed. Finally, the promising findings from mechanistic studies, large cohort studies, and small clinical trials obtained for autoimmune diseases (including type 1 diabetes, multiple sclerosis, and systemic lupus erythematosus), cardiovascular disorders, and overall reduction in mortality require further confirmation.

Seasonal Influence on the Risk of Relapse at a Rise of Antineutrophil Cytoplasmic Antibodies in Vasculitis Patients with Renal Involvement

Objective.

The objective of this study was to identify risk factors for a relapse at the time of an increase in antineutrophil cytoplasmic antibodies (ANCA) in patients with renal ANCA-associated vasculitis (AAV).

Methods.

All patients between January 2000 and November 2011 with renal AAV having an ANCA rise during remission were included. Differences in time to relapse since the ANCA rise were assessed using a Cox regression model. The level of 25-hydroxy Vitamin D (25(OH)D) was assessed at the ANCA rise and at a subsequent relapse or time-matched during remission.

Results.

Sixty patients had an ANCA rise, of whom 36 patients relapsed. Three risk factors were associated with a relapse at the time of the ANCA increase: previous disease activity not treated with cyclophosphamide or rituximab (HR 3.48, 95% CI 1.60–7.59), an ANCA rise during the fall season (HR 4.37, 95% CI 1.60–11.90), and an extended ANCA rise (HR 3.57, 95% CI 1.50–8.48). Levels of 25(OH)D significantly decreased during followup in relapsing patients, but not in patients who remained in remission (difference −6.3 ± 14.4, p = 0.017 vs 2.7 ± 16.3, p = 0.430).

Conclusion.

ANCA rises occurring during the fall season are more frequently followed by a relapse than ANCA rises occurring during other seasons. Although it is tempting to speculate that decreasing Vitamin D levels following the ANCA rise can be held responsible for the subsequent relapse, this remains to be determined.

Combined role of vitamin D status and CYP24A1 in the transition to systemic lupus erythematosus

OBJECTIVE

We examined whether measures of vitamin D were associated with transitioning to systemic lupus erythematosus (SLE) in individuals at risk for SLE.

METHODS

436 individuals who reported having a relative with SLE but who did not have SLE themselves were evaluated at baseline and again an average of 6.3 (±3.9) years later. Fifty-six individuals transitioned to SLE (≥4 cumulative American College of Rheumatology criteria). 25-Hydroxyvitamin D (25[OH]D) levels were measured by ELISA. Six single-nucleotide polymorphisms in four vitamin D genes were genotyped. Generalised estimating equations, adjusting for correlation within families, were used to test associations between the vitamin D variables and the outcome of transitioning to SLE.

RESULTS

Mean baseline 25[OH]D levels (p=0.42) and vitamin D supplementation (p=0.65) were not different between those who did and did not transition to SLE. Vitamin D deficiency (25[OH]D <20 ng/mL) was greater in those who transitioned compared with those who did not transition to SLE (46% vs 33%, p=0.05). The association between 25[OH]D and SLE was modified by CYP24A1 rs4809959, where for each additional minor allele increased 25[OH]D was associated with decreased SLE risk: zero minor alleles (adjusted OR: 1.03, CI 0.98 to 1.09), one minor allele (adjusted OR: 1.01, CI 0.97 to 1.05) and two minor alleles (adjusted OR: 0.91, CI 0.84 to 0.98). Similarly, vitamin D deficiency significantly increased the risk of transitioning to SLE in those with two minor alleles at rs4809959 (adjusted OR: 4.90, CI 1.33 to 18.04).

CONCLUSIONS

Vitamin D status and CYP24A1 may have a combined role in the transition to SLE in individuals at increased genetic risk for SLE.

Vitamin D Supplementation in Adolescents and Young Adults With Juvenile Systemic Lupus Erythematosus for Improvement in Disease Activity and Fatigue Scores: A Randomized, Double-Blind, Placebo-Controlled Trial

OBJECTIVE

Vitamin D has an important immunomodulatory effect, but there are no trials that directly address the boosting of serum levels of 25-hydroxyvitamin D (25[OH]D) in juvenile-onset systemic lupus erythematosus (SLE). The aim of this study was to evaluate the effect of vitamin D supplementation on disease activity and fatigue in juvenile-onset SLE.

METHODS

This study was a randomized, double-blind, placebo-controlled, 24-week trial. Forty juvenile-onset SLE patients were randomized (1:1) to receive oral cholecalciferol 50,000 IU/week (juvenile-onset SLE-VitD) or placebo (juvenile-onset SLE-PL). Medications remained stable throughout the study. Serum levels of 25(OH)D were measured using radioimmunoassay. Disease activity was assessed using the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and the European Consensus Lupus Activity Measurement (ECLAM). Fatigue was assessed using the Kids Fatigue Severity Scale (K-FSS).

RESULTS

At baseline, groups were similar regarding age, body mass index, organ involvement, glucocorticoid dose, use of immunosuppressive drugs, SLEDAI, ECLAM, K-FSS, and levels of 25(OH)D. After 24 weeks, the mean level of 25(OH)D was higher in the juvenile-onset SLE-VitD group than in the juvenile-onset SLE-PL group (P < 0.001). At the end of the intervention, a significant improvement in SLEDAI (P = 0.010) and in ECLAM (P = 0.006) was observed in the juvenile-onset SLE-VitD group compared to the juvenile-onset SLE-PL group. Regarding fatigue evaluation, a reduction of fatigue related to social life score was found in the juvenile-onset SLE-VitD group compared to the juvenile-onset SLE-PL group (P = 0.008). Cholecalciferol was well tolerated with no serious adverse events.

CONCLUSION

This study suggests that cholecalciferol supplementation for 24 weeks is effective in decreasing disease activity and improving fatigue in juvenile-onset SLE patients.

Vitamin D treatment for connective tissue diseases: hope beyond the hype?

The prevalence of vitamin D deficiency is increased among patients with CTDs. The active form of vitamin D (calcitriol) is a potent regulator of the immune system and may suppress inflammatory responses. This has led to claims that vitamin D may be a safe treatment, or a treatment adjunct, to reduce systemic inflammation in this patient population. It is important to note, however, that there is insufficient evidence from robust clinical trials to support these novel uses for vitamin D. In this review we examine the potential role of vitamin D as a treatment adjunct for CTDs. We will discuss how vitamin D may modulate the immune response and review the current evidence for using vitamin D to treat CTDs and their associated co-morbidities. We conclude that while there is much excitement about vitamin D in this context, further well-designed trials are needed to demonstrate its efficacy in the treatment of patients with CTDs.

A 24-month prospective study on the efficacy and safety of two different monthly regimens of vitamin D supplementation in pre-menopausal women with systemic lupus erythematosus

BACKGROUND

Low vitamin D (vit.D) serum levels are common in patients with systemic lupus erythematosus (SLE) and seem to correlate with higher disease activity. We investigated the effects of different regimens of vit.D supplementation in SLE patients with inactive disease.

METHODS

This 24-month prospective study included 34 SLE women who were randomized to receive, together with their ongoing treatment, a standard regimen (SR) of cholecalcipherol (25,000 UI monthly) or an intensive regimen (IR) (300,000 UI initial bolus followed by 50,000 UI monthly) for one year and then were switched to the other regimen in the second year. Patients were seen quarterly for assessment of 25-OH vit.D levels, disease activity, SLE serology and bone metabolism markers.

RESULTS

By intra-patient comparison, only the IR was found able to significantly raise vit.D serum levels. After 12 months, values above 30 ng/ml were found in 75% of patients in IR while in only 28% in SR. No significant differences in disease activity and SLE serology were found at any time point between SR and IR. No changes in the mineral metabolism were observed.

CONCLUSIONS

The IR was safe and effective in obtaining sufficient levels of vit.D in most SLE patients. However, both regimens of supplementation did not differently affect disease activity nor SLE serology.

Relationship of Circulating Anti-C3b and Anti-C1q IgG to Lupus Nephritis and Its Flare

BACKGROUND AND OBJECTIVES

Autoantibodies to complement C1q (anti-C1q) are associated with the diagnosis of lupus nephritis. In this study, we compare anti-C1q IgG with another complement autoantibody, anti-C3b IgG, as a biomarker of lupus nephritis and lupus nephritis flare.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Our investigation involved the Ohio SLE Study, a prospective observational cohort of patients with recurrently active lupus who were followed bimonthly. Serum anti-C1q and anti-C3b IgG levels were assessed cross-sectionally by ELISA in 40 normal controls and 114 patients in the Ohio SLE Study (41 nonrenal and 73 lupus nephritis) at study entry, and longitudinally in a subset of patients in the Ohio SLE Study with anti-C1q-positive lupus nephritis in samples collected every 2 months for 8 months leading up to lupus nephritis flare (n=16 patients).

RESULTS

In the cross-sectional analysis, compared with anti-C1q IgG, anti-C3b IgG was less sensitive (36% versus 63%) but more specific (98% versus 71%) for lupus nephritis. Only anti-C3b IgG was associated with patients with lupus nephritis who experienced at least one lupus nephritis flare during the Ohio SLE Study period (P<0.01). In the longitudinal analysis, circulating levels of anti-C1q IgG increased at the time of lupus nephritis flare only in patients who were anti-C3b positive (P=0.02), with significant increases occurring from 6 (38% increase) and 4 months (41% increase) before flare. Anti-C3b IgG levels also trended up at lupus nephritis flare, although the change did not reach statistical significance (P=0.07). Neither autoantibody increased 2 months before flare.

CONCLUSIONS

Although not as prevalent as anti-C1q IgG, anti-C3b IgG showed nearly complete specificity for lupus nephritis. The presence of anti-C3b IgG identified patients with lupus nephritis who were prone to flare and in whom serial measurements of markers associated with complement, such as anti-C1q IgG, may be useful to monitor lupus nephritis activity.

Systemic lupus erythematosus flare triggered by a spider bite

Systemic lupus erythematosus is a chronic autoimmune disease with a relapsing and remitting course characterized by disease flares. Flares are a major cause of hospitalization, morbidity and mortality in patients with systemic lupus erythematosus. Some triggers for these exacerbations have been identified, including infections, vaccines, pregnancy, environmental factors such as weather, stress and drugs. We report a patient who presented with a lupus flare with predominantly mucocutaneous, serosal and cardiac involvement after being bitten by a spider and we present the possible mechanisms by which the venom elicited such a reaction. To the best of our knowledge, this is the first such case reported in the literature.

Autoantibodies targeting glomerular annexin A2 identify patients with proliferative lupus nephritis

PURPOSE

Patients with systemic lupus erythematosus (SLE) frequently develop lupus nephritis (LN), a complication frequently leading to end stage kidney disease. Immune complex deposition in the glomerulus is central to the development of LN. Using a targeted proteomic approach, we tested the hypothesis that autoantibodies targeting glomerular antigens contribute to the development of LN.

EXPERIMENTAL DESIGN

Human podocyte and glomerular proteins were separated by SDS-PAGE and immunoblotted with sera from SLE patients with and without LN. The regions of those gels corresponding to reactive bands observed with sera from LN patients were analyzed using LC-MS/MS.

RESULTS

LN reactive bands were seen at approximately 50 kDa in podocyte extracts and between 36 and 50 kDa in glomerular extracts. Those bands were analyzed by LC-MS/MS and 102 overlapping proteins were identified. Bioinformatic analysis determined that 36 of those proteins were membrane associated, including a protein previously suggested to contribute to glomerulonephritis and LN, annexin A2. By ELISA, patients with proliferative LN demonstrated significantly increased antibodies against annexin A2.

CONCLUSION AND CLINICAL RELEVANCE

Proteomic approaches identified multiple candidate antigens for autoantibodies in patients with LN. Serum antibodies against annexin A2 were significantly elevated in subjects with proliferative LN, validating those antibodies as potential biomarkers.

Viruses as potential pathogenic agents in systemic lupus erythematosus

Genetic and environmental factors appear to contribute to the pathogenesis of systemic lupus erythematosus (SLE). Viral infections have been reported to be associated with the disease. A number of exogenous viruses have been linked to the pathogenesis of SLE, of which Epstein-Barr virus (EBV) has the most evidence of an aetiological candidate. In addition, human endogenous retroviruses (HERV), HRES-1, ERV-3, HERV-E 4-1, HERV-K10 and HERV-K18 have also been implicated in SLE. HERVs are incorporated into human DNA, and thus can be inherited. HERVs may trigger an autoimmune reaction through molecular mimicry, since homology of amino acid sequences between HERV proteins and SLE autoantigens has been demonstrated. These viruses can also be influenced by oestrogen, DNA hypomethylation, and ultraviolet light (UVB) exposure which have been shown to enhance HERV activation or expression. Viral infection, or other environmental factors, could induce defective apoptosis, resulting in loss of immune tolerance. Further studies in SLE and other autoimmune diseases are needed to elucidate the contribution of both exogenous and endogenous viruses in the development of autoimmunity. If key peptide sequences could be identified as molecular mimics between viruses and autoantigens, then this might offer the possibility of the development of blocking peptides or antibodies as therapeutic agents in SLE and other autoimmune conditions.

Vitamin D Levels Are Associated with Expression of SLE, but Not Flare Frequency

This study explores links between vitamin D deficiency (25(OH)D = 50 nmol/L) and serological autoimmunity (ANA > 1 : 80) and frequency of self-reported flares (SRF) in participants with clinical autoimmunity (SLE). 25(OH)D levels of 121 females were quantified and compared. The cohort consisted of 80 ACR defined SLE patients and 41 age and sex matched controls. Association analysis of log2 (25(OH)D) levels and ANA 80 positivity was undertaken via two-sample t-tests and regression models. Significant differences were found for 25(OH)D levels (mean: control 74 nmol/L (29.5 ng/ml); SLE 58 nmol/L (23.1 ng/ml), P = 0.04), 25(OH)D deficiency (P = 0.02). Regression models indicate that, for a twofold rise in 25(OH)D level, the odds ratio (OR) for ANA-positivity drops to 36% of the baseline OR. No link was found between SRF-days and 25(OH)D levels. Our results support links between vitamin D deficiency and expression of serological autoimmunity and clinical autoimmunity (SLE). However, no demonstrable association between 25(OH)D and SRF was confirmed, suggesting independent influences of other flare-inducing factors. Results indicate that SLE patients have high risk of 25(OH)D deficiency and therefore supplementation with regular monitoring should be considered as part of patient management.

Correlation between serum 25(OH)D values and lupus disease activity: an original article and a systematic review with meta-analysis focusing on serum VitD confounders

Notwithstanding that several original studies and some systematic reviews have been undertaken on the subject "correlation between serum values of vitamin D (VitD) and lupus disease activity," there is still no consensus on the importance of sectional measurement of serum VitD in the prediction of disease activity and important confounders in estimation of serum VitD. Medline, Web of Knowledge, and Scopus databases were searched from 1995 to 2013. The following medical subject heading (MeSH) terms and/or text words were used: "Vitamin D" OR "25OHD" OR "25(OH)D" combined with "systemic lupus erythematosus" OR "lupus" OR "SLE." References cited in the identified articles were also manually searched. Human studies in any language were included. Original research on this topic was also carried out on 82 lupus patients, considering important VitD confounders according to our systematic review and we included them in the meta-analysis. A total of 35 studies were registered for this study. Only 11 of these pointed to this correlation by Pearson test. The pooled Pearson correlation (r) of associations between disease activity and VitD was -0.365 (95% CI: -0.536, -0.165) with significant heterogeneity (p = 0.001 I (2 )= 93%). Sensitivity analysis resulted in no significant differences. The most important adjustable confounders considered by researchers were drugs, especially hydroxychloroquine, prednisolone and supplementary VitD, body mass index (BMI) and proteinuria or renal function. Only proteinuria was reported to influence VitD concentration strongly. BMI was another probable influencing factor. Our original research presented no correlation between VitD and SLEDAI (p = 0.68, r s = 0.003). This meta-analysis demonstrated that most of the studies on the relationship between VitD and lupus disease activity that found no correlation did not present the details of the statistics. However, analyzing 11 studies, most of which found a reverse correlation and reported it in detail, and our study found a weak reverse correlation between those two items. Systematic review of confounders showed that BMI, medications and kidney involvement were the most remarkable ones reported by researchers.

Lower vitamin D levels are associated with higher systemic lupus erythematosus activity, but not predictive of disease flare-up

Objectives

Growing evidence suggests that vitamin D plays a key role in the pathogenesis and progression of autoimmune diseases, including systemic lupus erythematosus (SLE). Recent studies have found an association between lower serum 25-hydroxyvitamin D (25(OH)D) levels and higher SLE activity. We studied the relationship between 25(OH)D levels and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score, and we assessed for the first time the role of vitamin D in predicting SLE flare-ups.

Methods

Serum 25(OH)D levels were measured in 170 patients with SLE who were prospectively followed up for 6 months (Plaquenil LUpus Systemic study, ClinicalTrials.gov number NCT00413361).

Results

The mean SLEDAI score was 2.03±2.43 and 12.3% patients had active disease (SLEDAI ≥6). The mean 25(OH)D level was 20.6±9.8 ng/mL. Deficiency (25(OH)D <10 ng/mL) was observed in 27 (15.9%), insufficiency (10≤25(OH)D<30) in 112 (65.9%) and optimal vitamin D status (25(OH)D≥30) in 31 (18.2%) patients. In multivariate analysis, female gender (p=0.018), absence of defined antiphospholipid syndrome (p=0.002) and higher creatinine clearance (p=0.004) were predictive of lower 25(OH)D levels. In multivariate analysis, lower 25(OH)D levels were associated with high SLE activity (p=0.02). Relapse-free survival rate was not statistically different according to the vitamin D status during the 6-month follow-up (p=0.22).

Conclusions

We found a low vitamin D status in the majority of patients with SLE, and a modest association between lower 25(OH)D levels and high disease activity. There was no association between baseline 25(OH)D levels and relapse-free survival rate.

Vitamin D, steroid hormones, and autoimmunity

The endogenous serum metabolite of vitamin D (calcitriol, 1,25(OH)2 D3 ) is considered a true steroid hormone (D hormone), and like glucocorticoids (GCs) and gonadal hormones, may exert several immunomodulatory activities. Serum vitamin D deficiency (25(OH) D), and therefore reduced 1,25(OH)2 D3 availability, is considered a risk factor for several chronic/inflammatory or autoimmune conditions, including infectious diseases, type 1 diabetes, multiple sclerosis, and especially autoimmune rheumatic diseases (ARD). In ARD in particular, 1,25(OH)2 D3 regulates both innate and adaptive immunity, potentiating the innate response (antimicrobial activity) but reducing adaptive immunity (antigen presentation, T and B cell activities). Regarding a possible synergism between vitamin D and GCs, several studies show that 1,25(OH)2 D3 has significant additive effects on dexamethasone-mediated inhibition of human lymphocyte and monocyte proliferation. Conversely, vitamin D deficiency seems to play a role in increasing autoantibody production by B cells, and seasonal vitamin D declines may trigger flares in ARD, as recently shown. Finally, 1,25(OH)2 D3 seems to reduce aromatase activity and limit the negative effects related to increased peripheral estrogen metabolism (cell proliferation, B cell overactivity).

Greater seasonal cycling of 25-hydroxyvitamin D is associated with increased parathyroid hormone and bone resorption

SUMMARY

This analysis assessed whether seasonal change in 25-hydroxyvitamin D concentration was associated with bone resorption, as evidenced by serum parathyroid hormone and C-terminal telopeptide concentrations. The main finding was that increased seasonal fluctuation in 25-hydroxyvitamin D was associated with increased levels of parathyroid hormone and C-terminal telopeptide.

INTRODUCTION

It is established that adequate 25-hydroxyvitamin D (25(OH)D, vitamin D) concentration is required for healthy bone mineralisation. It is unknown whether seasonal fluctuations in 25(OH)D also impact on bone health. If large seasonal fluctuations in 25(OH)D were associated with increased bone resorption, this would suggest a detriment to bone health. Therefore, this analysis assessed whether there is an association between seasonal variation in 25(OH)D and bone resorption.

METHODS

The participants were (n = 279) Caucasian and (n = 88) South Asian women (mean (±SD); age 48.2 years (14.4)) who participated in the longitudinal Diet, Food Intake, Nutrition and Exposure to the Sun in Southern England study (2006-2007). The main outcomes were serum 25(OH)D, serum parathyroid hormone (sPTH) and serum C-terminal telopeptide of collagen (sCTX), sampled once per season for each participant.

RESULTS

Non-linear mixed modelling showed the (amplitude/mesor) ratio for seasonal change in log 25(OH)D to be predictive of log sPTH (estimate = 0.057, 95 % CI (0.051, 0.063), p < 0.0001). Therefore, individuals with a higher seasonal change in log 25(OH)D, adjusted for overall log 25(OH)D concentration, showed increased levels of log sPTH. There was a corresponding significant ability to predict the range of seasonal change in log 25(OH)D through the level of sCTX. Here, the corresponding parameter statistics were estimate = 0.528, 95 % CI (0.418, 0.638) and p ≤ 0.0001.

CONCLUSIONS

These findings suggest a possible detriment to bone health via increased levels of sPTH and sCTX in individuals with a larger seasonal change in 25(OH)D concentration. Further larger cohort studies are required to further investigate these preliminary findings.

Current daily glucocorticoid use and serum creatinine levels are associated with lower 25(OH) vitamin D levels in Thai patients with systemic lupus erythematosus

BACKGROUND AND OBJECTIVE

Because vitamin D deficiency has been previously reported in patients with systemic lupus erythematosus (SLE), we decided to examine the prevalence of vitamin D deficiency in Thai SLE patients, to identify possible independent factors affecting serum 25-hydroxyvitamin D(2) and D(3) [25(OH)] vitamin D levels, and to examine the associations of serum 25(OH) vitamin D and disease activity and damage in Thai SLE patients.

METHODS

A cross-sectional study was performed in 101 SLE patients. Blood samples were prospectively collected. The levels of 25(OH) vitamin D were measured by radioimmunoassay. The cutoffs for vitamin D deficiency and insufficiency were 30 and 20 ng/mL, respectively. Demographic, clinical, and laboratory data were collected, and their associations with 25(OH) vitamin D level were examined by univariate and multivariate linear regression analyses.

RESULTS

The level of 25(OH) vitamin D (mean [SD]) was 27.9 (7.6). Seventeen patients (17%) had vitamin D deficiency, 41 patients (41%) had vitamin D insufficiency, and 43 patients (42%) had normal vitamin D levels. Two thirds of the patients were taking relatively low-dose vitamin D supplementations. Current daily glucocorticoid dose and serum creatinine levels were negatively correlated with vitamin D levels (β = -0.207, P = 0.023; and β = -3.770, P = 0.003, respectively). There were no associations between disease activity or damage and 25(OH) vitamin D levels.

CONCLUSIONS

Vitamin D deficiency and insufficiency are common in SLE patients despite more than half of them taking vitamin D supplementations. Higher serum creatinine level and higher current daily glucocorticoid dose are associated with lower serum 25(OH) vitamin D levels. These patients may require higher doses of vitamin D supplementations.

[Vitamin D and autoimmunity]

Vitamin D acts at several levels in the immune systems to maintain immune tolerance. Vitamin D deficiency is a plausible environmental risk factor for autoimmune disease. Basic, genetic and epidemiological studies indicate a potential role of vitamin D in the prevention and the treatment of autoimmune diseases. Most of the epidemiological studies are cross-sectional, so that they are insufficient to establish a direct link between vitamin D deficiency and both disease risk and disease activity. Randomized, controlled trials are necessary.

Vitamin D deficiency and risk for rheumatic diseases: an update

PURPOSE OF REVIEW

The role of vitamin D in situations other than calcium homeostasis and bone health has become very topical. It is apparent that vitamin D has significant effects on the immune system and as such may contribute to the pathogenesis of autoimmune disease. This review examines the evidence-to-date that vitamin D has a role in immune-mediated rheumatic disorders.

RECENT FINDINGS

Low vitamin D status is reported in many inflammatory rheumatic conditions. In some this extends to an association with disease activity. Vitamin D acts on a number of cells involved in both innate and acquired immunity biasing the adaptive immune system away from Th17 and Th1, towards Th2 and Tregs. Deficiency accordingly could encourage autoimmunity. Direct evidence for this plausible mechanism in specific diseases remains largely to be demonstrated. To date, there is a dearth of controlled trials of vitamin D in prophylaxis or therapy.

SUMMARY

Vitamin D deficiency may well be an important factor in autoimmune rheumatic disease, including initial disease development and worsening the disease once present. This is testable and there is a pressing need for therapeutic studies.

The role of vitamin D supplementation in patients with rheumatic diseases

Vitamin D is a dietary vitamin that can also be synthesized in adequate amounts from cholesterol in most mammals exposed to sunlight. Vitamin D has classical roles in calcium and phosphate metabolism, and thus the skeleton; however, this molecule also has nonclassical effects that might influence the function of the immune, cardiovascular and endocrine systems. Vitamin D deficiency, due to insufficient sunlight exposure, dietary uptake and/or abnormalities in its metabolism, has been associated with rheumatic diseases, and both the classical and nonclassical effects of vitamin D might be of relevance to patients with rheumatic disease. However, conclusive data from intervention trials demonstrating the relationship between vitamin D levels and pathogenetic processes separate from classical effects of this molecule are lacking. Furthermore, the majority of studies linking vitamin D to health outcomes, harmful or beneficial, are observational in nature, linking clinical events to vitamin D exposure or serum levels of vitamin D metabolites. Evidence from high quality, prospective, double-blind, placebo-controlled, randomized trials should be obtained before vitamin D supplementation is recommended in the treatment of the many rheumatic conditions in which deficiency of this compound has been implicated. Herein, we review the evidence for vitamin D supplementation in the management of patients with rheumatic diseases.

Transverse myelitis

Transverse myelitis (TM) includes a pathobiologically heterogeneous syndrome characterized by acute or subacute spinal cord dysfunction resulting in paresis, a sensory level, and autonomic (bladder, bowel, and sexual) impairment below the level of the lesion. Etiologies for TM can be broadly classified as parainfectious, paraneoplastic, drug/toxin-induced, systemic autoimmune disorders, and acquired demyelinating diseases. We discuss the clinical evaluation, workup, and acute and long-term management of patients with TM. Additionally, we briefly discuss various disease entities that may cause TM and their salient distinguishing features, as well as disorders that may mimic TM.

Vitamin D receptor gene BsmI, FokI, ApaI and TaqI polymorphisms and the risk of systemic lupus erythematosus

Recently, several studies have demonstrated the role of vitamin D receptor (VDR) polymorphisms in the development of systemic lupus erythematosus (SLE); however, these results are inconsistent between different cohorts. Therefore, we studied the prevalence of the VDR FokI (rs2228570), BsmI (rs1544410), ApaI (rs7975232) and TaqI (rs731236) genotypes and alleles in SLE patients (n = 258) and healthy individuals (n = 545) in a Polish population. We did not observe significant differences for either the VDR FokI, BsmI, ApaI and TaqI genotype and allele frequencies in patients with SLE and healthy individuals. However, the frequency of the VDR F/F and F/f genotypes of FokI was statistically different between patients with renal disease and patients without this symptom OR = 3.228 (1.534–6.792, p = 0.0014), p_corr = 0.0476)]. There was no association of the studied VDR BsmI, ApaI and TaqI polymorphisms with clinical manifestations and laboratory profiles in patients with SLE. Our study indicates that the studied VDR FokI variant might increase the risk of some clinical presentations in patients with SLE.

Juvenile onset systemic lupus erythematosus: a possible role for vitamin D in disease status and bone health

Purpose: In juvenile onset systemic lupus erythematosus (JoSLE), evidence for the association between vitamin D status, lupus activity, and bone health is very limited and not conclusive. The aim of this study was, therefore, to assess in JoSLE patients the possible relevance of vitamin D deficiency in disease and bone parameters. Methods: Fifty-seven JoSLE patients were initially compared to 37 age, race and body mass index (BMI) -matched healthy controls. The serum concentration of 25 hydroxyvitamin D (25OHD) was determined by radioimmunoassay. Patients with 25OHD deficiency (≤20 ng/mL) were compared to those with levels >20 ng/mL. Disease activity was evaluated by SLE Disease Activity Index (SLEDAI). Bone mineral density (BMD) and body composition (BC) were measured using dual-energy X-ray absorptiometry (DXA). Results: 25OHD levels were similar in patients and controls (21.44 ± 7.91 vs 22.54 ± 8.25 ng/mL, p = 0.519), regardless of supplementation (65% of patients and none in controls). Thirty-one patients with 25OHD deficiency (≤20 ng/mL) were further compared to the 26 JoSLE patients with levels >20 ng/mL. These two groups were well-balanced regarding vitamin D confounding variables: age ( p = 0.100), ethnicity ( p = 1.000), BMI ( p = 0.911), season (p = 0.502 ), frequency of vitamin D supplementation ( p = 0.587), creatinine ( p = 0.751), renal involvement ( p = 0.597 ), fat mass ( p = 0.764), lean mass ( p = 0.549), previous/current use of glucocorticoids(GC) ( p = 1.0), immunosuppressors ( p = 0.765), and mean current daily dose of GC ( p = 0.345). Patients with vitamin D deficiency had higher SLEDAI (3.35 ± 4.35 vs 1.00 ± 2.48, p = 0.018), lower C4 levels (12.79 ± 6.78 vs 18.38 ± 12.24 mg/dL, p = 0.038), lower spine BMD (0.798 ± 0.148 vs 0.880 ± 0.127 g/cm2, p = 0.037 ) and whole body BMD (0.962 ± 0.109 vs 1.027 ± 0.098 g/cm2, p = 0.024). Conclusion: JoSLE vitamin D deficiency, in spite of conventional vitamin D supplementation, affects bone and disease activity status independent of therapy and fat mass reinforcing the recommendation to achieve adequate levels.