Introduction: Despite, various preventive efforts on conventional cardiovascular disease (CVD) risk factors, the incidence of CVD in rheumatoid arthritis (RA) patients increases continuously. To solve this conundrum one needs more investigations.
Aim: The present study was conducted to evaluate the plasma paraoxonase (PON) activity along with the markers of systemic inflammation, oxidative stress and disease activity score-28 (DAS28) in RA patients and clarify their role in determining the probability of RA patients to develop future CVD risk.
Materials and methods: Plasma PON, total antioxidant activity (TAA), C-reactive protein (CRP), synovial interleukin-6 (IL-6) and erythrocyte malondialdehyde (MDA) levels were estimated in 40 RA patients aged 40-55 years aged and 40 age-matched healthy controls. The data obtained were compared statistically by using Student's t-test and Pearson correlation test.
Results: Besides dyslipidaemia, marked reduction in plasma PON and TAA (p< 0.05) were observed in RA patients as compared with that of healthy controls. Erythrocyte MDA, plasma CRP and synovial IL-6 levels were increased significantly (p<0.05) in RA patients. PON was negatively correlated with MDA (r = - 0.672; p < 0.001), CRP (r = -0.458; p<0.05), IL-6 (r = -0.426; p<0.05) and DAS28 (r = -0.598; p < 0.001), and positively correlated with HDL cholesterol (r = 0.648; p<0.001) and TAA (r = 0.608; p< 0.001) levels in RA patients.
Conclusion: Alteration in PON activity might contribute to the progression of future CVD risk in RA patients, which may result from interplay of several confounding factors, such as inflammation, oxidative stress and dyslipidaemia. Furthermore, plasma PON activity, CRP and TAA levels could be considered as non-traditional factors to predict CVD risk. Thus, it is suggested that future drugs could be developed to target the non-traditional risk factors in RA patients.
Keywords: C-reactive protein; Interleukin-6; Malondialdehyde; Total antioxidant activity.