The aims of this study were to investigate a possible relationship between the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and some acute phase reactant (APR) levels in patients with ankylosing spondylitis (AS).
Twenty outpatients who fulfilled the modified New York criteria for AS were included in the study. Laboratory activity was assessed by examining erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), haptoglobin (Hp), and beta2 microglobulin (beta2MG). Disease activity was assessed according to the BASDAI, which includes a 10-point visual analogue scale to measure pain, fatigue, morning stiffness, swelling, and areas of local tenderness.
When APR values were analyzed for the BASDAI, a positive correlation between CRP and BASDAI was observed (r = 0.556, P < 0.05). There was no clear, statistically significant correlation between BASDAI and the other APRs (ESR, r = 0.328, P > 0.05; Hp, r = 0.035, P > 0.05; and beta2MG, r = -0.190, P > 0.05).
Our data suggest that CRP is a better marker of disease activity than ESR, Hp, and beta2MG.