Effect of TNF inhibitors on lipid profile in rheumatoid arthritis: a systematic review with meta-analysis

Background Patients with rheumatoid arthritis (RA) are at increased risk of cardiovascular disease. Lipid changes related to inflammation have been described in RA. Tumour necrosis factor alpha (TNF alpha) inhibitor (TNFi) treatment is effective in controlling inflammation and decreasing the number of cardiovascular events. Objective To assess the change in lipid levels with TNFi treatment in patients with RA by systematic review and meta-analysis. Methods A Medline search was performed for articles published up to March 2011. Reports describing values for total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TGs), atherogenic index (AI) and apolipoprotein B/A (apoB/A) collected before and after TNFi initiation were included. Data were analysed according to short-, mid- and long-term treatment. Statistical analysis of pre-post data was performed by comprehensive meta-analysis. A random effects model was used when there was evidence of heterogeneity. Results The search retrieved 32 articles, of which 13 prospective before/after studies were analysed. Longterm TNFi treatment was associated with increased levels of HDL (+0.27 mmol/l, p<0.0001) and TC (+0.27 mmol/l, p=0.03), whereas LDL levels and AI remained unchanged. After long-term treatment, TG levels increased (+0.28 mmol/l, p<0.001) and apoB/A decreased (-0.3, p<0.0001). Conclusion The presumed cardioprotective effects of TNFi in RA do not seem to be explained by quantitative lipid changes since long-term treatment has no effect on LDL levels or on AI. Increased HDL levels could have some beneficial effects, but this needs to be confirmed by prospective studies with long-term follow-up.