Prealbumin Correlates with C-reactive Protein in Rheumatic Musculoskeletal Diseases

Prealbumin is a blood component tested for nutrition monitoring, which could be affected during inflammation. This study aimed to investigate the relationships between prealbumin and C-reactive protein (CRP) in inflammatory rheumatic musculoskeletal diseases (RMDs), including Takayasu arteritis, antineutrophil cytoplasmic antibody-associated vasculitis, systemic lupus erythematosus, Behcet's disease and polymyositis/dermatomyositis.

A total of 52 healthy controls and 508 RMD patients were included. We collected 3714 clinical and laboratory records from June 2011 to August 2019, and the longest follow-up period was eleven years. The associations between prealbumin and CRP, the globulin gap, the albumin-to-globulin ratio, and IgG were evaluated.

Prealbumin had a high correlation coefficient (r=-0.497, P<0.001), consistent changes over time with CRP, and a high area under the curve [AUC=0.777 (95% CI 0.76-0.795)] for CRP. The statistical relationship between the prealbumin and CRP was not affected by sex, ethnicity or age. Among RMDs, prealbumin showed the strongest correlation with CRP in Takayasu arteritis (r=0.607, P<0.001). In addition, a moderate relationship was observed between prealbumin and IgG, the globulin gap and the albumin-to-globulin ratio.

Prealbumin is closely related to CRP in Chinese patients with five chronic inflammatory RMDs, which may be due to the influence of chronic inflammation during the course of disease.