ESR1 and rheumatoid arthritis: In this regard, a study of 145 RA patients showed that baseline calprotectin levels were independently associated with the van der Heijde modified Sharp score (SvH) and the Rheumatoid Arthritis Articular Damage Score (RAAD score), even when adjusted for CRP, ESR, rheumatoid factor, DAS28, sex and age (123).