Background Rheumatoid arthritis (RA) is a chronic inflammatory disease that is strongly associated with cardiovascular (CV) disease. In early active arthritis, an unfavourable lipid profile has been found. A strong association exists between the development of arthritis and auto-antibodies, such as Rheumatoid Factor (RF) and anti-cyclic citrullinated protein (aCCP).
Objectives Considering the relation between inflammation and lipid profiles, we sought to investigate whether differences in lipid profile were also associated with the development of arthritis.
Methods Total cholesterol (TC), high-density lipoprotein cholesterol (HDLc), low-density lipoprotein cholesterol (LDLc), triglycerides (TG), apolipoprotein (apo) A1 and apoB were determined at baseline in sera of 348 arthralgia patients positive for RF and/or aCCP. Statin use and cardiovascular co-morbidities were recorded at baseline. Development of arthritis was followed over a median (IQR) of 24 (14-49) months. Differences in lipid profiles between patients who developed arthritis and patients who did not, and differences between aCCP positive and aCCP negative patients were analysed with Student’s T test or Mann Whitney U tests as appropriate. Predictive properties of lipid profiles for the development of arthritis were analysed with Cox proportional hazard analyses.
Results One hundred sixteen patients developed arthritis after a median (IQR) follow-up of 12 (6-23) months, of whom 91% were diagnosed with RA according to the 2010 ACR/EULAR criteria. Lower lipid levels were observed in patients who developed arthritis than in patients who did not, although the difference did not reach statistical significance for all lipids. HDL levels and ApoA1 levels were significantly lower in the arthritis group. Total Cholesterol and ApoA1 were predictive for arthritis development as continuous variables (hazard ratios (HR); 95%CI: 0.84; 0.71-1.00; and 0.44; 0.26-0.79, respectively). HDL was predictive for arthritis development only when analysed as categorical variable (HR; 95%CI: 0.64; 0.43-0.94). aCCP status was a confounder for all lipids. No other confounders were found. aCCP positive patients had significantly lower total cholesterol levels. For the other lipids, trends were seen towards lower lipid levels in aCCP positive patients. After adjustment for aCCP status, only ApoA1 was significantly predictive for arthritis development (HR; 95%CI: 0.52; 0.29-0.92) whereas for HDL an obvious trend was observed (HR; 95%CI: 0.70; 0.47-1.02).
Conclusions Seropositive arthralgia patients who developed arthritis had overall lower lipid levels than those who did not develop arthritis. Lower lipid levels were also inversely associated with aCCP status. ApoA1 and HDL levels add to the predictive value of aCCP for the development of arthritis.
Disclosure of Interest None Declared