Vitamin D and Graves’ Disease: A Meta-Analysis Update

Abstract

The association between vitamin D levels and Graves’ disease is not well studied. This update review aims to further analyze the relationship in order to provide an actual view of estimating the risk. We searched for the publications on vitamin D and Graves’ disease in English or Chinese on PubMed, EMBASE, Chinese National Knowledge Infrastructure, China Biology Medical and Wanfang databases. The standardized mean difference (SMD) and 95% confidence interval (CI) were calculated for the vitamin D levels. Pooled odds ratio (OR) and 95% CI were calculated for vitamin D deficiency. We also performed sensitivity analysis and meta-regression. Combining effect sizes from 26 studies for Graves’ disease as an outcome found a pooled effect of SMD = −0.77 (95% CI: −1.12, −0.42; p < 0.001) favoring the low vitamin D level by the random effect analysis. The meta-regression found assay method had the definite influence on heterogeneity (p = 0.048). The patients with Graves’ disease were more likely to be deficient in vitamin D compared to the controls (OR = 2.24, 95% CI: 1.31, 3.81) with a high heterogeneity (I2 = 84.1%, p < 0.001). We further confirmed that low vitamin D status may increase the risk of Graves’ disease.

Vitamin D in Graves Disease: Levels, Correlation with Laboratory and Clinical Parameters, and Genetics

“…In the epidemiological part of the study, we found lower vitamin D levels in patients with GD compared to controls, a result that is supported by findings of other smaller studies [12, 13] and recent meta-analyses [10, 11]. The vitamin D levels were in the same range as previously reported in a Chinese study [12].…”

“…Genetic variation in genes involved in vitamin D metabolism has been associated with several autoimmune disorders including autoimmune thyroid disease [2-7]. Several studies suggest that individuals with Graves disease (GD) have lower vitamin D levels than the general population [8-11]; however, data on the relationship between the levels of vitamin D and clinical parameters in GD [12, 13] or therapeutic issues [14-16] are limited. The aim of the present study was to compare vitamin D levels in a large number of newly diagnosed patients with GD with those of the general population and to correlate the vitamin D levels at diagnosis with laboratory and clinical parameters in patients with GD.…”

Low vitamin D status is associated with hypothyroid Hashimoto’s thyroiditis

“…28 In addition to the aforementioned meta-analysis, another metaanalysis of 26 studies showed that patients with GD are more likely to be deficient in vitamin D compared to controls with a high heterogeneity. 29 The relationship between vitamin D status and the severity, onset or presence of remission of GD were not further analyzed in the current study. The conflicting results regarding the correlation between vitamin D and AITD, HT or GD are in part due to cross-sectional studies with a small number of subjects, the heterogeneity of the study population, seasonal variation in blood sampling, inter-method analytical variability of vitamin D assays, and different definitions of vitamin D deficiency/insufficiency.…”

Treatment options in the young patient with Graves' disease

“…A logical strategy would be to target the immune response and whilst there have been small and potentially promising studies of immune‐modulatory agents such as rituximab in adults there has been no formal trial in young people to date where the unmet need is greater. Whether vitamin D and selenium status influence the likelihood of remission also needs to be established . Adjunctive treatment with agents such as cholestyramine has not been studied in the young either .…”

“…Whether vitamin D and selenium status influence the likelihood of remission also needs to be established. 28,29 Adjunctive treatment with agents such as cholestyramine has not been studied in the young either. 30 Utilizing the effect of supraphysiological doses of iodine on thyroid hormone release with ongoing iodine therapy for years (rather than a brief course to render the individual euthyroid in the initial phase) is a further potential therapy.…”