Relationship between Vitamin D levels and pain and disease activity in patients with newly diagnosed axial spondyloarthritis

Abstract

ObjectivesTo explore the relationship between Vitamin D levels and pain and disease activity in patients with newly diagnosed axial spondyloarthritis (axSpA). MethodsA convenience sample of 131 newly diagnosed axSpA patients and 60 healthy controls was recruited from July 2016 to December 2018. Serum 25-hydroxyvitamin D [25(OH)D] was measured to assess vitamin D levels. Disease activity was assessed by objective indicators [Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), the Bath Ankylosing Spondylitis Metrology Index (BASMI)], patient-reported questionnaires [the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), and the Bath Ankylosing Spondylitis Functional Index (BASFI)]. Pain intensity and interference were also assessed. ResultsVitamin D insufficiency [serum 25(OH) D levels<50 nmol/L]was found in 46 (35.1%) and 25 (43.3%) of the axSpA patients and the healthy controls, respectively. Female patients had higher risk (OR:4.928; 95% CI: 1.921–12.642) for vitamin D insufficiency than male patients. Vitamin D was positively correlated with CRP, ESR level, the BASFI, and the BASMI. Logistic regression showed that vitamin D levels were not associated with pain, or disease activity in the newly diagnosed axSpA patients. Gender was the only predictive variable for vitamin D levels. ConclusionsVitamin D insufficiency was prevalent in both newly diagnosed axSpA patients and healthy controls. There was no association between vitamin D and pain and disease activity in the newly diagnosed axSpA patients. Monitoring vitamin D levels is important and early intervention for vitamin D insufficiency is needed, especially in female patients.