Lipid profile and risks of cardiovascular diseases in conditions of rheumatoid arthritis.

Cardiovascular diseases (CVD) belong to the leading causes of mortality worldwide. Elevated levels of total cholesterol and LDL cholesterol are associated with increased incidence of CVD in the population. Reversely, reduction of lipoprotein levels in plasma results in a positive impact on CVD prevention. Patients with rheumatoid arthritis (RA), a chronic inflammatory disease, have markedly increased mortality risk due to CVD, despite lower lipoprotein levels in comparison with common population. This is known as the “lipid paradox”. RA itself represents an independent CVD risk factor acting as an inflammatory component. Inflammation, manifested by systemic elevated concentrations of pro-inflammatory cytokines, mainly interleukin 6 (IL-6), interleukin 1β (IL-1β) and the tumour necrosis factor α (TNF-α) in RA, is considered to be the main contributor of atherogenesis via its impact on lipoprotein metabolism and on the biology of the arterial wall. Atherosclerosis, a complex process including a number of mechanisms, is not only regarded as dysregulation of lipid metabolism, but also as a chronic inflammatory disease. This review summarizes the newest findings about the qualitative and quantitative alterations of lipids and lipoproteins affected by low-grade inflammation triggered by RA and their consequences on atherosclerosis.