Apo B and Lp(a): A clinician's perspective

Disorders of lipoprotein metabolism are common and are thought to account for at least 50% of all cardiac risk, Significant advances have been made in the dietary and pharmacologic treatment of dyslipidemic states. Outcome studies have shown that medications, especially hydroxymethylglutaryl-CoA reductase inhibitors, substantially lower cardiac risk. Yet a majority of patients do not appear to benefit from medication that adds expense and potential morbidity and generally is prescribed on an indefinite basis. On the other hand, some patients with dyslipidemias would theoretically benefit from drug therapy, but do not qualify for treatment on the basis of national guidelines. Fractionation of HDL and LDL cholesterol, begun two decades ago, has improved clinicians' understanding of an individual patient's risk, Now it is time to extend this understanding by measuring apolipoprotein B and lipoprotein(a) in patients whose risk is unclear from standard lipoprotein values.