Relationship Between Some Acute Phase Reactants and the Bath Ankylosing Spondylitis Disease Activity Index in Patients with Ankylosing Spondylitis

OBJECTIVES: 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). METHODS: 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. RESULTS: 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). CONCLUSIONS: Our data suggest that CRP is a better marker of disease activity than ESR, Hp, and beta2MG.