Increased lipid levels but unchanged atherogenic index in rheumatoid arthritis patients treated with biologic disease modifying antirheumatic drugs: published experience

Background Cardiovascular disease (CVD) is a major cause of increased mortality ill rheumatoid arthritis (RA) patients, and it is recommended to treat risk factors for CVD in RA patients aggressively, including increased lipid levels. However, the effect of biological disease modifying antirheumatic drugs (DMARD) on the lipid profile of RA patients remains under-researched, and what data exist are often contradictory. Objectives To review available data published to date on lipid profile changes in RA patients treated with biologic DMARDs. Methods We searched the PubMed database without time limits until January 31, 2008 for original clinical trials regarding the effect of biological DMARDs on the lipid profiles of RA patients, tabulating total cholesterol, LDL HDL and atherogenic index (ratio of total cholesterol to HDL) data for RA patients treated with biologic DMARDs. Percent change values from baseline to end of study were calculated. Results Eighteen studies fulfilled our inclusion criteria. The total cholesterol levels of patients treated with biological DMARDs was reported to increase in eleven studies (mean change 14.8%). One study reported a decrease (change 4.07%), and six reported no significant change. In HDL levels, nine studies reported increases (mean change 13.1%), two reported decreases (mean change 8.69%) and six reported no significant changes. Five studies reported an increase in LDL levels (mean change 11.2%), no studies reported a decrease, and six studies reported no significant change. The atherogenic index was reported to increase in two studies (mean change 4.27%), decrease in two studies (mean change 7.26%), and not significantly change in nine studies. Only a third of the reviewed articles reported on the LDL/HDL ratio, but of those that did, two reported an increase (mean change 4.55%), one reported a decrease (change 8.03%), and three reported no significant changes. Discussion Our data suggest increases in lipid levels between baseline and end of study in clinical trials of RA patients treated with biologic DMARDs. However, the clinical implications of this finding with regard to cardiovascular outcomes are not clear in part due to the fact that in most of the studies the atherogenic index was not significantly changed from baseline to end of study. Those studies that do provide data on effects on cholesterol rarely provide information on the complete lipid profile.