Linkage of calprotectin with inflammation, activity and treatment response of rheumatoid arthritis: a meta-analysis

Abstract

Aim: This meta-analysis aimed to investigate the clinical value of calprotectin in rheumatoid arthritis (RA) patients. Methods: The data regarding blood calprotectin levels in RA patients were retrieved from PubMed, Embase, Web of Science and Cochrane databases. Results: Thirty-one eligible articles were included. Calprotectin was increased in RA patients compared with healthy controls (mean difference [MD] = 1.48, 95% CI: 1.16-1.79). Calprotectin was positively associated with C-reactive protein (correlation coefficient [CC] = 0.58, 95% CI: 0.53-0.63) and disease activity score (CC = 0.48, 95% CI: 0.38-0.58) in RA patients. Interestingly, calprotectin showed an increased trend in RA responders compared with nonresponders, but without statistical significance (MD = 0.38, 95% CI: -0.09-0.85). Conclusion: Blood calprotectin relates to disease risk, inflammation and activity in RA patients. Plain language summary This meta-analysis included published data about blood calprotectin levels in rheumatoid arthritis (RA) patients. After integrated analyses, it was observed that blood calprotectin levels were higher in RA patients compared with healthy subjects; calprotectin was positively related to systemic inflammation and disease activity in RA patients. However, blood calprotectin levels failed to predict treatment outcomes in RA patients.