LIPOPROTEIN(A) - PHYSIOLOGICAL-FUNCTION, ASSOCIATION WITH ATHEROSCLEROSIS, AND EFFECTS OF LIPID-LOWERING DRUG-THERAPY

OBJECTIVE: To review the structure and physiologic function of lipopro tein(a) [Lp(a)], review the association of Lp(a) with the development of atherosclerosis, and to critically evaluate the current literature regarding the effects of lipid-lowering drug therapy on Lp(a) serum co ncentrations. DATA SOURCES: English language clinical and animal studi es, abstracts, and review articles pertaining to Lp(a). STUDY SELECTIO N AND DATA EXTRACTION: Relevant human and animal studies examining Lp( a)'s role in atherosclerosis and the effect of drug therapy on Lp(a) s erum concentrations. DATA SYNTHESIS: Possible physiologic functions an d potential atherogenic mechanisms of Lp(a) are discussed. Evidence su pporting the association of Lp(a) with atherosclerosis is presented. S tudies evaluating the effects of lipid-lowering drug therapy on Lp(a) concentrations are reviewed and critiqued. CONCLUSIONS: Lp(a) concentr ations are correlated with the risk of atherosclerotic vascular diseas e (AVD) in both animal models and human studies. Drug therapies that h ave produced a consistent reduction in Lp(a) concentration include nia cin alone or in combination with a bile acid sequestrant or neomycin. However, additional, larger studies are needed to evaluate the ability of drug therapies to specifically reduce elevated Lp(a) concentration s. Preliminary information suggests that reduction in Lp(a) concentrat ions may be associated with atherosclerotic plaque regression. Althoug h drugs are available to lower Lp(a), one cannot conclude that lowerin g of Lp(a) is warranted until clinical trials demonstrating beneficial effects have been published.