Vitamin D status in patients with autoimmune bullous dermatoses: a meta-analysis

Background The association between autoimmune bullous dermatoses (AIBD) and serum vitamin D levels has been revealed by some studies, however, inconsistent.Objectives We aimed to evaluate the difference in vitamin D status between AIBD patients and controls.Methods We searched the studies about the vitamin D status of AIBD patients in electronic databases published before January 2020. Mean difference (MD) and 95% confidence intervals (CI) of eligible studies were calculated in meta-analyses of 25(OH)D levels. Pooled odds ratio (OR) and 95%CI were used in analyses of the prevalence of hypovitaminosis D. Different subgroup analyses, sensitivity analyses and publication bias assessment were conducted.Results We included nine case-control studies in the meta-analysis. Vitamin D level was significantly lower in both pemphigus (MD: −7.02, 95%CI: −10.30 to −3.74) and bullous pemphigoid (BP) (MD: −6.37, 95%CI: −12.15 to −0.58) patients than that in controls. Active pemphigus patients were at higher risk of presenting hypovitaminosis D (OR: 6.95, 95%CI: 1.37–35.25).Conclusions Abnormal vitamin D status are more common in AIBD patients than that in general population. Therefore, regular monitoring of vitamin D levels and vitamin D supplementation should be considered as part of the management strategy for AIBD.