LIPOPROTEINS AND HOMOCYST(E)INE AS RISK-FACTORS FOR ATHEROSCLEROSIS -ASSESSMENT AND TREATMENT

Two new important independent risk factors for coronary artery disease (CAD) have been identified: lipoprotein (a) [Lp(a)] and homocyst(e)in e. Both are associated with increased frequency of cardiovascular even ts, both coronary and peripheral. Measurement of these two factors sho uld be considered in patients with symptomatic CAD, stroke, a strong f amily history (but low other conventional risk factors); in first degr ee relatives of those with very high Lp(a) or homocyst(e)ine levels; a nd in other individuals in whom the need for an aggressive treatment o f metabolic risk factors is indicated, While treatment of high serum L p(a) with drugs is difficult it appears from the epidemiological or cl inical evidence that the additional risk due to Lp(a) can be drastical ly lowered by decreasing the patient's low density lipoprotein (LDL) c holesterol levels to below 3 mmol/L. The treatment of increased homocy st(e)ine can be easily accomplished by vitamin B-6 or folic acid admin istration, Various analyses describing the value of positive tests for diagnosis of atherosclerosis indicate that overall risk evaluated by computer models from Framingham data, use of total high density lipopr otein (HDL) cholesterol ratio and/or tile National Cholesterol Educati on Program (NCEP) II guidelines are the best predictors of future card iovascular events. The stategic aim for treatment regimens should be t hreefold lower serum LDL cholesterol levels; decrease serum triglyceri des (and triglyceride-rich lipoproteins); and increase HDL chblesterol . Niacin and statin drugs are the most cost effective means to achieve the former and niacin and fibrates to achieve the latter goal, Where target LDL cholesterol levels can be achieved with less expensive stat in preparations their use may be economically advantageous.