Elevated serum 25-hydroxyvitamin D: a potential indicator of remission in Takayasu arteritis patients with normal ESR and CRP levels

The goal of the present study was to investigate the correlation between serum 25-hydroxyvitamin D [25(OH)D] levels and disease remission in Takayasu arteritis (TAK) patients. This retrospective study included 59 patients in the study group and 80 patients in the validation cohort with TAK. After 6 months of therapy, patients were re-evaluated, and serum 25(OH)D levels were compared before and after treatment. Correlations between changes in 25(OH)D levels and changes in disease activity scores (NIH, ITAS2010, ITAS.A) were analyzed. Additionally, a predictive cut-off value for disease remission was determined. After 6 months of therapy, serum 25(OH)D levels in TAK patients significantly increased compared to baseline [(18.33 ± 7.25)µg/L vs (11.77 ± 4.14) µg/L] (P < 0.001). Positive correlations were observed between the increasing changes in the 25(OH)D level and the decreasing changes in the reduced NIH, ITAS2010, and ITAS.A scores (r = 0.455, P < 0.001; r = 0.495, P < 0.001; and r = 0.352 P = 0.006, respectively). A change of 8.45 µg/L in 25(OH)D level was identified as the predictive cut-off value for TAK remission (sensitivity 54.1