Serum calcidiol level associated with axial spondyloarthritis disease activity.

Background: Vitamin D deficiency is frequent among axial spondyloarthritis (SpA) patients. However, the association between vitamin D level and axial SpA disease activity is still in debate. This study aimed to determine the correlation between serum calcidiol level and axial SpA disease activity. Methods: A cross-sectional study involving thirty axial SpA patients was conducted. All patients were diagnosed by rheumatologists according to the ASAS 2010 criteria. Axial SpA disease activities were measured using ASDASCRP score, and calcidiol level was examined using the ECLIA method. Results: The calcidiol levels had median value of 16.56 ng/ml (7.68-52 ng/ml). Calcidiol deficiency (<20 ng/ml) was found in 66.7% patients, calcidiol insufficiency (20-29.9 ng/ml) found in 16.7% patients, and normal level (≥30 ng/ml) found in16.7% patients. Mean of ASDAS-CRP score was 3.36±0.96. Low disease activity was in 10% patients, high disease activity in 56.7% patients, and very high disease activity in 33.3% patients. There was significant correlation between calcidiol level and ASDAS-CRP score (r = -0.464, P = 0.01). Conclusion: Serum calcidiol level was significant negative correlated with axial SpA disease activity. [ABSTRACT FROM AUTHOR]