The relationship of serum vitamin D receptor levels with disease activity and clinical parameters in patients with ankylosing spondylitis

Özet

Objectives: The aim of this study was to investigate the relationship between serum vitamin D receptor (SVDR) levels and disease activity parameters in patients with ankylosing spondylitis (AS).Patients and methods: Between July 2016 and January 2017, a total of 62 patients (51 males, 11 females; mean age 36.5±12.8 years;range, 23 to 49 years) with AS and 32 healthy volunteers (25 males, 7 females; mean age 41.57±13.6 years; range, 26 to 48 years) were includedin the study. The SVDR levels were measured using the enzyme-linked immunosorbent assay. Erythrocyte sedimentation rate (ESR) andserum C-reactive protein (CRP) levels were recorded. The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) scores were usedto assess disease activity.Results: Although there was no significant difference between the patient and control groups (p=0.66), SVDR levels were significantlyelevated in patients with active AS (BASDAI score ≥4) (p=0.01). The SVDR levels significantly increased in AS patients with peripheral jointinvolvement and enthesitis (p=0.01, p=0.05, respectively). The SVDR levels significantly elevated in patients treated with non-steroidal antiinflammatorydrugs, compared to those treated with biological agents and control group (p=0.01, p=0.03, respectively). The SVDR levelswere positively correlated with the BASDAI, CRP and ESR in the patient group (p=0.01, r=0.751; p=0.01, r=0.75; p=0.01, r=0.81, respectively).Conclusion: Our study results suggest that serum SVDR levels are associated with the disease activity and clinical parameters in patientswith AS. Based on these findings, SVDR level may be used as a marker of disease activity in AS.