A PROSPECTIVE INVESTIGATION OF ELEVATED LIPOPROTEIN(A) DETECTED BY ELECTROPHORESIS AND CARDIOVASCULAR-DISEASE IN WOMEN - THE FRAMINGHAM HEART-STUDY

Background Sinking prebeta lipoprotein is a putative marker for elevat ed levels of lipoprotein (a). Although prospective data suggest that i ncreased plasma lipoprotein (a) is an independent risk factor for coro nary heart disease in men, no prospective studies are available in wom en. Methods and Results From 1968 through 1975, sinking prebeta lipopr otein was determined by paper electrophoresis in 3103 women Framingham Heart Study participants who were free of prevalent cardiovascular di sease. A sinking prebeta lipoprotein band was detectable in 434 of the women (14%) studied. The median follow-up interval was approximately 12 years. Incident cardiovascular disease was associated with band pre sence using a proportional hazards model that included age, smoking, b ody mass index, systolic blood pressure, glucose intolerance, low- and high-density lipoprotein cholesterol, and ECG left ventricular hypert rophy. Multivariable adjusted relative risk estimates (with 95% confid ence intervals) for outcomes in the band present versus absent groups were as follows: myocardial infarction (82 events), 2.37 (1.48 to 3.81 ); intermittent claudication (62 events), 1.94 (1.07 to 3.50); cerebro vascular disease (83 events), 1.88 (1.12 to 3.15); total coronary hear t disease (174 events), 1.61 (1.13 to 2.29); and total cardiovascular disease (305 events), 1.44 (1.09 to 1.91). A subset analysis indicated that band presence was 50.9% sensitive and 95.4% specific for detecti ng plasma lipoprotein (a) levels of > 30 mg/dL, the threshold value li nked to increased cardiovascular disease risk in men. Conclusions Sink ing prebeta lipoprotein was a valid surrogate for elevated lipoprotein (a) levels in Framingham Heart Study women. Band presence and, equiva lently, elevated plasma lipoprotein (a), was a strong, independent pre dictor of myocardial infarction, intermittent claudication, and cerebr ovascular disease. Confirmation of these findings in other longitudina l studies of women is needed.