NEW YORK (Reuters Health) – In a small study of rheumatoid arthritis patients, treatment with the anti-tumor necrosis factor (anti-TNF) agent infliximab appeared to increase the antioxidative capacity of HDL cholesterol.

This finding may help explain prior reports suggesting a cardioprotective effect for anti-TNF therapy in rheumatoid arthritis patients, Dr. C. Popa, from Radboud University Nijmege Medical Centre, the Netherlands, and colleagues conclude.

As reported in the June issue of the Annals of the Rheumatic Diseases, the researchers measured plasma lipids and paraoxonase activity in 45 rheumatoid arthritis patients before, during, and after 6 months of infliximab therapy. The team also examined the ability of HDL cholesterol to block copper-induced oxidation of LDL cholesterol in vitro.

Although plasma HDL cholesterol levels did not change during the study period, paraoxonase activity increased significantly, the report indicates (p < 0.03). Moreover, at 6 months, a significant improvement in HDL total antioxidative capacity was noted (p = 0.015). The increase in paraoxonase was concurrent to the decline in inflammatory status, the authors note. The improvement in HDL antioxidative capacity at 6 months, by contrast, appeared to be a specific effect of TNF blockade. “Our results underline the importance of evaluating HDL antioxidative properties in addition to HDL concentrations, especially in those populations in which the predictive value of traditional cardiovascular risk factors is limited,” Dr. Popa’s team concludes. Reference:
Ann Rheum Dis 2009;68:868-872.