Disease activity in patients with rheumatoid arthritis increases serum levels of apolipoprotein C-III.

Rheumatoid arthritis (RA) has been unequivocally associated with an increased burden of accelerated atherosclerosis, which, at least in part, is a consequence of the inflammation present in the disease. Apolipoprotein C-III (ApoC3) is a key molecule in triglycerides metabolism that has been linked to cardiovascular (CV) disease. Our objective was to study how ApoC3 is related to the characteristics of RA, paying special attention to its relationship with the inflammatory activity of the disease. Cross-sectional study that included 430 patients with RA. In these patients, data related to the disease, classic CV risk factors, complete lipid profile, and serum ApoC3 levels were evaluated. A multivariable regression analysis was performed to study the relationship of the characteristics of RA with ApoC3. Abdominal circumference, obesity, type 2 diabetes, and circulating triglycerides were significantly associated with higher ApoC3 serum levels. Furthermore, C-reactive protein and erythrocyte sedimentation rate, as well as the disease activity score -DAS28- were significantly related to a higher circulating ApoC3 after multivariable analysis. Patients included in the moderate or high disease activity groups had higher ApoC3 serum levels compared to those in remission (beta coefficient 1.28 [95% confidence interval 0.16-2.39] mg/dl, p=0.025) when adjusting for confounders. The use of prednisone, disease-modifying anti-rheumatic drugs and anti-tumour necrosis factor therapies was associated with lower values of ApoC3. The activity of the disease in patients with RA is independently associated with higher serum levels of ApoC3.