Abstract 386: Sex Differences in Vitamin D Alter Inflammation During Heart Disease

An estimated 1 billion people worldwide have deficient or insufficient levels of vitamin D (VitD). Considerable evidence indicates that VitD deficiency is associated with an increased risk of autoimmune and cardiovascular disease (CVD), yet it remains unclear whether low VitD is simply a biomarker or has a true pathologic role. In this study we examined how sex differences in VitD influences various CVDs. We found that patients with CVD had significantly lower VitD than healthy controls (no ICD9/10 codes). In myocarditis patients low VitD correlated to poor ejection fraction (EF) in women with myocarditis (p=0.02), but high VitD correlated with low EF in men (p=0.04). In VDR knockout mice we found that VDR decreased myocarditis in females (p=2E-8) but increased inflammation in males (p=0.03) with an increase in total immune cells (p=0.02), CD3, CD4 and CD8 T cells (p=0.04), and the inflammasome in females. VDR altered Treg (p=0.04), mast cells (p=0.04) and cytokine profiles in males. Additionally, sera VitD levels were significantly higher in WT male mice with myocarditis compared to females. Our findings in VDR mice indicate that VitD/VDR reduces myocarditis in females, but increases disease in males. These data suggest that VitD sufficiency may increase inflammation in men, while VitD deficiency may make disease worse in women. These findings suggest that Vitamin D may have a role in the pathogenesis of inflammatory and cardiovascular disease.