Abstract 47: Genetically Elevated Low-Density Lipoprotein Cholesterol is Associated with Aortic Valve Calcification and Incident Aortic Stenosis
Background: Although plasma low density lipoprotein cholesterol (LDL-C) appears to be a causative factor in animal models of aortic valve (AV) disease, randomized trials with cholesterol lowering therapies in established disease have failed to reduce progression. We sought to evaluate whether life-long genetic elevations in LDL-C, high density lipoprotein cholesterol (HDL-C) and triglycerides (TG) are associated with AV disease.
Methods: Using 144 single nucleotide polymorphisms associated with LDL-C, HDL-C or TG in genomewide association studies (GWAS), we constructed three separate genetic risk scores (GRS). We estimated the association between each GRS and (1) the presence of AV calcium determined by computed tomography in 6942 participants of white European ancestry from the Cohorts for Heart and Aging Research in Genetic Epidemiology (CHARGE) consortium using summary level GWAS data and; (2) incidence of aortic stenosis in 28,585 participants from the Malmo Diet and Cancer Study (MDCS) over a mean follow-up time of 15.8 years.
Results: The LDL-C GRS, but not the HDL-C or the TG GRS, was associated with presence of AV calcium (OR per predicted mmol/L LDL-C, 1.38 95% CI 1.09-1.74; p=0.007). The LDL-C GRS was also associated with incident aortic stenosis (HR per mmol/L LDL-C, 3.04 (1.34-6.91, p=0.008). In sensitivity analyses excluding SNPs also associated with HDL-C or TG to reduce pleiotropy, the LDL-C GRS remained associated with AV calcium (OR per predicted mmol/L LDL-C 1.39 95% CI 1.04-1.90; p=0.03) and aortic stenosis (HR per mmol/L LDL-C 3.85, 95% CI 1.37-10.79, p=0.01). Further analyses to exclude residual pleiotropic effects of HDL-C and TG, did not materially change these findings.
Conclusions: Genetic predisposition to increased LDL-C is associated with presence of AV calcium and incidence of aortic stenosis, providing novel supportive evidence that LDL-C is a causal factor for the development of AV disease. Earlier intervention to reduce LDL-C merits further investigation to prevent AV disease.
Author Disclosures: G. Thanassoulis: None. K. Luk: None. C.A. Schulz: None. J. Engert: None. D. Owens: None. R. Do: None. G. Hindy: None. G. Rukh: None. L. Dufresne: None. S.S. Rich: None. S. Kathiresan: None. M. Orho-Melander: None. V. Gudnason: None. C.J. O'Donnell: None. W.S. Post: None. J.G. Smith: None.
- © 2014 by American Heart Association, Inc.