An evaluation of vitamin D status in individuals with systemic lupus erythematosus

Abstract

Systemic lupus erythematosus (SLE) is a multi-system inflammatory disease where genetic susceptibility coupled with largely undefined environmental factors is reported to underlie the aetiology of the disease. One such factor is low vitamin D status. The primary source of vitamin D is endogenous synthesis following exposure of the skin to UVB light. Photosensitivity, sunlight avoidance and the use of sun protection factor in combination with medications prescribed to treat the symptoms of the disease, puts SLE patients at increased risk of vitamin D deficiency. Decreased conversion of 25-hydroxyvitamin D to the metabolically active form, 1,25-dihydroxyvitamin D 3 , is possible, due to renal impairment common in SLE putting additional stress on vitamin D metabolism. The majority of studies have identified low 25-hydroxyvitamin D in SLE patients, albeit using varying cut-offs ( < 25 to < 80 nmol/l). Of these studies, fifteen have investigated a link between status and disease activity with conflicting results. Variation with disease activity index measures used alongside methodological limitations within the study design may partially explain these findings. This review discusses the importance of optimal vitamin D status in SLE, critically evaluates research carried out to date that has investigated vitamin D in SLE, and highlights the need for a well-designed observational study that controls for diet, medication use, dietary supplements, UV exposure and seasonality, that uses sensitive methods for measuring vitamin D status and disease activity in SLE to conclusively establish the role of vitamin D in SLE.

Optimal management of fatigue in patients with systemic lupus erythematosus: a systematic review

“…Sunlight avoidance, use of sunscreen, renal insufficiency, and drugs (such as chloroquine and prednisone) prescribed to treat the symptoms of SLE interfere with vitamin D metabolism and put patients with SLE at risk for vitamin D deficiency. 49 In fact, hypovitaminosis D is common in patients with SLE. 49 …”

The Implication of Vitamin D and Autoimmunity: a Comprehensive Review

“…After around 2 years of oral vitamin D treatment, mean 25(OH)D levels in all treated patients were increased. However, the majority (71 %) of the SLE patients still had insufficient levels of vitamin D. Although it appears that there was no improvement of SLE severity after oral vitamin D supplementation in this study, the effect of vitamin D intervention in SLE has not been extensively investigated, probably because there are too many confounding factors that could affect vitamin D metabolism in clinical medications used to treat SLE [106]. …”

Why are kids with lupus at an increased risk of cardiovascular disease?

“…Thus the immunomodulating effects of vitamin D may explain the reported epidemiological associations between vitamin D status and a large number of autoimmune and inflammatory diseases [100]. Several reviews [101,102] have shown a high prevalence of vitamin D deficiency in patients with SLE, showing evidence of antibodies to 1,25 (OH) 2 D, the biologically active form of vitamin D, which is rarely measured in clinical practice [103,104]. Mok et al have suggested that 25-(OH)D levels are as specific as antibodies to C1q complement factor (anti-C1q) for detecting concurrent renal activity in SLE and Wu et al [105] have correlated vitamin D levels with CV risk factors [106].…”