Relationship Between Vitamin D Status and Brain Perfusion in Neuropsychiatric Lupus.

Abstract

Neuropsychiatric manifestation of lupus (NPSLE) is related with vitamin D (vit-D) deficiency which is possibly amenable to supplementation. This study was done to explore link of serum vit-D level and clinical mini-mental state examination (MMSE) with brain perfusion SPECT (BS) in patients with NPSLE. Patients who underwent BS with the diagnosis of NPSLE and had serum levels of vit-D and MMSE within a span of 1 month were retrospectively included. The BS DICOM data were used to generate 3D surface images of brain for visual identification of regional hypoperfusion, and the z-scores from eZIS software and then to perform voxel-based regression analysis in order to explore association between serum vit-D level and cerebral perfusion deficit using SPM8. Distribution of serum vit-D level was checked across MMSE and BS z-score using R. A total 19 patients with means ± SD age of 28.4 ± 9.2 years, having mean levels of serum vit-D of 18.7 ± 9.8 ng/ml and mean MMSE scores 24.2 ± 1.6, had undergone BS. The eZIS-derived z-score fall in the category of normal in six (31.6%), mild perfusion deficit (PD) in 10 (52.6%) and moderate PD in three (15.8%) with the means ± SD of z-score being 0.52 ± 0.2, 1.72 ± 0.2, and 2.33 ± 0.2. Voxel-based analysis revealed significant positive correlation between vit-D level and hypoperfusion in brain regions related to cognitive function (p<0.05). Serum vit-D levels were significantly lower in NPSLE patients with lower MMSE scores as well as in higher eZIS z-score (p < 0.01). Our results may support the utility of vit-D supplementation in NPSLE and applicability of BS as a clinical adjunct for monitoring response to vit-D supplementation.