Patients with vitiligo have elevated serum homocysteine and decreased vitamin B12 levels, and these levels are associated with disease activity level, according to results published in the Journal of the American Academy of Dermatology.
The investigators performed a systematic review and meta-analysis of studies evaluating serum homocysteine, folate, and vitamin B12 concentrations in patients with vitiligo to help elucidate the pathogenesis of the disease. They searched online databases from April 30, 2018, to May 15, 2018, to identify those studies in which levels of serum homocysteine, folate, and vitamin B12 were compared between patients with vitiligo and controls. A random effects model was used for all the studies assessed.
A total of 22 studies that comprised 1448 patients with vitiligo were included in the analysis. Individuals with vitiligo had significantly higher serum homocysteine levels (standardized mean difference [SMD], 0.550; 95% CI, 0.262-0.838; I2, 87.3%) and lower vitamin B12 levels (SMD, –0.240; 95% CI, –0.592 to 0.111; I2, 85.3%) compared with controls. In contrast, serum folate concentrations did not differ significantly between those with and without vitiligo (SMD, –0.240; 95% CI, –0.592 to 0.111; I2, 85.5%).
A subgroup analysis demonstrated that higher levels of homocysteine correlated with patients’ disease activity. In addition, vitamin B12 levels were significantly lower regardless of disease activity, and levels were similar in patients with progressive and stable vitiligo.
Major limitations of this analysis are that the studies included were heterogeneous in design and that serum homocysteine levels may be affected by a number of different factors.
The investigators concluded that additional research on vitiligo is warranted to reveal the underlying mechanisms of hyperhomocysteinemia and vitamin B12 deficiency and to examine the therapeutic potential of homocysteine-lowering strategies.
Tsai T-Y, Kuo C-Y, Huang Y-C. Serum homocysteine, folate, and vitamin B12 levels in patients with vitiligo and their potential roles as disease activity biomarkers: A systematic review and meta-analysis [published online August 27, 2018]. J Am Acad Dermatol. doi: 10.1016/j.jaad.2018.08.029