CRP and major depressive disorder: AS-related factors with independent associations with depression included disease activity as measured with the Bath AS Disease Activity Index (BASDAI; OR 2.48; 95 CI 1.06 to 5.78) and AS Disease Activity Score-C-reactive protein (ASDAS-CRP; OR 2.48; 95% CI 1.06 to 5.78), and quality of life as measured by the AS Quality of Life questionnaire (ASQoL; OR 1.22; 95% CI 1.12 to 1.33) [22].