Link between lipoprotein(a), CVD identified
MedWire News: Genetic study results indicate that lipoprotein (Lp)(a) may raise cardiovascular disease (CVD) risk by encouraging atherosclerotic stenosis rather than venous thrombosis.
Numerous general population studies have shown a link between elevated Lp(a) levels and an increased CVD risk, but the underlying mechanism has remained unclear, explain Børge Nordestgaard, from Copenhagen University Hospital in Denmark, and co-authors.
The findings from the current study therefore "represent important new knowledge, imperative for defining optimal future preventive treatment strategies targeting elevated Lp(a) levels," they say.
As reported in the journal Atherosclerosis, Thrombosis, and Vascular Biology, the team measured plasma Lp(a) and genetically elevated Lp(a) levels in 48,512 individuals of Danish origin..
Of these, 38,753 were recruited from two general population studies that assessed the rates of both venous thrombosis and combined thrombosis and atherosclerosis in coronary arteries. The remaining 9759 participants were obtained from three case-control studies designed to investigate atherosclerotic stenosis rates.
After analysis of participant Lp(a) levels and Lp(a)-specific genotypes, no significant association was identified between venous thrombosis risk and Lp(a) levels or genotypes among participants from the general population studies.
However, when the risk for coronary, carotid, and femoral atherosclerotic stenosis was analysed among participants in the case-control studies, Lp(a) level and genotype showed significant association with these three types of atherosclerotic stenosis.
Indeed, coronary, carotid, and femoral atherosclerotic stenosis risks rose by 12%, 17%, and 16%, respectively, when plasma Lp(a) levels doubled.
A two-fold increase in plasma Lp(a) levels was also associated with 17% and 21% increases in the risk for myocardial infarction (MI) among the general population and case-control groups, respectively.
This association was seen among both groups because MI is an event arising from the combined effect of thrombosis and atherosclerosis in coronary arteries, say the authors.
Nordestgaard and team conclude that the study findings "are compatible with elevated Lp(a) levels primarily promoting atherosclerotic stenosis."
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2012
By Lauretta Ihonor