Serum active 1,25(OH)2D, but not inactive 25(OH)D vitamin D levels are associated with cardiometabolic and cardiovascular disease risk in psoriasis

Abstract

Background and aims: Vitamin D exists as an inactive 25-hydroxyvitamin D (25(OH)D) in the bloodstream, which is converted to active 1,25-dihydroxyvitaminD (1,25(OH)₂D) in target tissues. Cohort studies reporting cardiovascular disease among individuals with low vitamin D are inconsistent and solely measure 25(OH)D. Psoriasis, a chronic inflammatory disease, is a vitamin D deficient state and is associated with increased cardiovascular disease risk. While serum 25(OH)D is routinely measured, we hypothesized that measurement of 1,25(OH)₂D in psoriasis may perform better than 25(OH)D in capturing cardiovascular risk.

Methods: Consecutive psoriasis patients (N = 122) at baseline underwent FDG PET/CT and CCTA scans to measure visceral adipose volume, aortic vascular uptake of FDG, and coronary plaque burden respectively. Blood levels of both 1,25(OH)₂D and 25(OH)D were measured by chemiluminescence (LIAISON XL DIaSorin, Stillwater, MN).

Results: The psoriasis cohort was middle-aged (mean ± SD: 49.6 ± 13.0), predominantly male (n = 71, 58%), in majority Caucasians (n = 98, 80%), and had moderate-to-severe skin disease [psoriasis area severity index score, PASI score, med.

(iqr): 5.5 (3.2-10.7)], with almost one-fourth of the cohort on biologic psoriasis therapy for skin disease management (n = 32, 27%) at baseline. Interestingly, serum levels of 1,25(OH)₂D but not 25(OH)D were found to be inversely associated with visceral adipose, a marker of cardiometabolic risk in fully adjusted models (β = - 0.43, p = 0.026 and β = -0.26 p = 0.13). Similarly, we found an inverse relationship between 1,25(OH)₂D, but not 25(OH)D, and aortic vascular uptake of FDG independent of traditional risk factors (β = -0.19, p = 0.01). Finally, we found that serum 1,25(OH)₂D, but not 25(OH)D, was inversely associated with non-calcified coronary plaque burden, as measured by CCTA independent of traditional risk factors (β = -0.18, p = 0.03).

Conclusions: In conclusion, we demonstrate that low 1,25(OH)₂D levels were associated with visceral adipose volume, vascular uptake of FDG and coronary plaque burden independent of traditional risk factors, suggesting that 1,25(OH)₂D may better capture the cardiometabolic risk associated with vitamin D deficient states.

Keywords: Coronary artery disease; Imaging; Inflammation; Psoriasis; Vitamin D.