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Genetic inhibition of CETP, ischemic vascular disease and mortality, and possible adverse effects

Trine Holm Johannsen1, Ruth Frikke-Schmidt, Jesper Schou

  • 1Department of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark.

Abstract

Insights

Genetic cholesteryl ester transfer protein (CETP) inhibition is linked to reduced risk of ischemic events and mortality. This protective effect occurs without the adverse effects seen with torcetrapib.

Area of Science:

  • Cardiovascular Genetics
  • Pharmacogenomics
  • Lipid Metabolism

Background:

  • Torcetrapib, a cholesteryl ester transfer protein (CETP) inhibitor, increased mortality and ischemic cardiovascular disease risk despite lipid profile improvements.
  • Adverse effects of torcetrapib necessitate investigation into alternative CETP inhibition strategies.

Purpose of the Study:

  • To investigate the association between genetic variation in the CETP gene and the risk of ischemic events and total mortality.
  • To determine if genetic CETP inhibition confers a protective effect without the adverse effects observed with torcetrapib.

Main Methods:

  • Prospective cohort study (Copenhagen City Heart Study) of 10,261 individuals followed for up to 34 years.
  • Analysis of two common genetic variants in CETP associated with reduced CETP activity, mimicking pharmacological inhibition.
  • Assessment of ischemic vascular events, myocardial infarction, ischemic cerebrovascular disease, ischemic stroke, and total mortality.

Main Results:

  • Individuals with 4 high-density lipoprotein cholesterol-increasing alleles showed a 14% increase in HDL-C and decreases in triglycerides and LDL-C.
  • Significant reductions in hazard ratios were observed for ischemic vascular events (0.76), ischemic heart disease (0.74), myocardial infarction (0.65), ischemic cerebrovascular disease (0.77), and ischemic stroke (0.71).
  • Total mortality was reduced (hazard ratio 0.88), and CETP genotypes did not associate with markers of torcetrapib's adverse effects.

Conclusions:

  • Genetic CETP inhibition is associated with reduced risk of major ischemic vascular diseases and increased longevity.
  • The observed antiatherogenic lipid profile supports a protective role for CETP inhibition.
  • Genetic CETP inhibition offers a potential therapeutic strategy without the adverse effects linked to torcetrapib.

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