Takayasu's arteritis ( TAK ) is a chronic, large-vessel vasculitis. Vitamin D, as a steroidal hormone, has recently been shown to have immunoregulatory and immunosuppressive effects.
Low vitamin D levels are demonstrated in various autoimmune disorders.
The aim of this study is to investigate vitamin D levels in patients with Takayasu's arteritis. A comprehensive review of vitamin D levels in systemic vasculitides ( SVs ) is also performed.
The study included 36 patients with Takayasu's arteritis, 28 patients with Behçet's disease as disease control and 30 sex-matched healthy controls.
Plasma 25-hydroxy vitamin D [ 25(OH)vitamin D ] levels were measured with high-performance liquid chromatography. Deficiency was defined as 25(OH)vitamin D levels below 25 nmol/l and insufficiency as below 50 nmol/l.
Plasma 25(OH)vitamin D levels were significantly lower in patients with Takayasu's arteritis ( 16.93 ± 10.62 nmol/l ) than healthy controls ( 64.63 ± 21.82 nmol/l ).
Vitamin D level in patients with Behçet's disease ( 38.8 ± 20.9 nmol/l ) is lower than healthy controls but higher than patients with Takayasu's arteritis.
The frequency of vitamin D deficiency was 83.3% in patients with Takayasu's arteritis compared to 3.3% in healthy controls.
Plasma 25(OH)vitamin D levels were same between clinically active and inactive patients.
In literature review, very few studies were found to investigate vitamin D in systemic vasculitides.
In conclusion, researchers observed a high prevalence of vitamin D deficiency in patients with systemic vasculitides.
As various immune effects of vitamin D on mononuclear cells and arterial endothelium is shown, vitamin D deficiency can be a predisposing factor for immune activation in systemic vasculitis.
Researchers therefore suggest monitorization and replacement of vitamin D status in all Takayasu's arteritis and other systemic vasculitis patients. ( Xagena )
Alibaz-Oner F et al, J Clin Lab Anal 2015; Epub ahead of print