Association of Triglyceride-Lowering LPL Variants and LDL-C-Lowering LDLR Variants With Risk of Coronary Heart Disease

JAMA. 2019 Jan 29;321(4):364-373. doi: 10.1001/jama.2018.20045.

Abstract

Importance: Triglycerides and cholesterol are both carried in plasma by apolipoprotein B (ApoB)-containing lipoprotein particles. It is unknown whether lowering plasma triglyceride levels reduces the risk of cardiovascular events to the same extent as lowering low-density lipoprotein cholesterol (LDL-C) levels.

Objective: To compare the association of triglyceride-lowering variants in the lipoprotein lipase (LPL) gene and LDL-C-lowering variants in the LDL receptor gene (LDLR) with the risk of cardiovascular disease per unit change in ApoB.

Design, setting, and participants: Mendelian randomization analyses evaluating the associations of genetic scores composed of triglyceride-lowering variants in the LPL gene and LDL-C-lowering variants in the LDLR gene, respectively, with the risk of cardiovascular events among participants enrolled in 63 cohort or case-control studies conducted in North America or Europe between 1948 and 2017.

Exposures: Differences in plasma triglyceride, LDL-C, and ApoB levels associated with the LPL and LDLR genetic scores.

Main outcomes and measures: Odds ratio (OR) for coronary heart disease (CHD)-defined as coronary death, myocardial infarction, or coronary revascularization-per 10-mg/dL lower concentration of ApoB-containing lipoproteins.

Results: A total of 654 783 participants, including 91 129 cases of CHD, were included (mean age, 62.7 years; 51.4% women). For each 10-mg/dL lower level of ApoB-containing lipoproteins, the LPL score was associated with 69.9-mg/dL (95% CI, 68.1-71.6; P = 7.1 × 10-1363) lower triglyceride levels and 0.7-mg/dL (95% CI, 0.03-1.4; P = .04) higher LDL-C levels; while the LDLR score was associated with 14.2-mg/dL (95% CI, 13.6-14.8; P = 1.4 × 10-465) lower LDL-C and 1.9-mg/dL (95% CI, 0.1-3.9; P = .04) lower triglyceride levels. Despite these differences in associated lipid levels, the LPL and LDLR scores were associated with similar lower risk of CHD per 10-mg/dL lower level of ApoB-containing lipoproteins (OR, 0.771 [95% CI, 0.741-0.802], P = 3.9 × 10-38 and OR, 0.773 [95% CI, 0.747-0.801], P = 1.1 × 10-46, respectively). In multivariable mendelian randomization analyses, the associations between triglyceride and LDL-C levels with the risk of CHD became null after adjusting for differences in ApoB (triglycerides: OR, 1.014 [95% CI, 0.965-1.065], P = .19; LDL-C: OR, 1.010 [95% CI, 0.967-1.055], P = .19; ApoB: OR, 0.761 [95% CI, 0.723-0.798], P = 7.51 × 10-20).

Conclusions and relevance: Triglyceride-lowering LPL variants and LDL-C-lowering LDLR variants were associated with similar lower risk of CHD per unit difference in ApoB. Therefore, the clinical benefit of lowering triglyceride and LDL-C levels may be proportional to the absolute change in ApoB.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apolipoproteins B / blood*
  • Case-Control Studies
  • Cholesterol, LDL / blood*
  • Coronary Disease / blood
  • Coronary Disease / genetics*
  • Female
  • Genetic Predisposition to Disease*
  • Genetic Variation*
  • Humans
  • Lipoprotein Lipase / genetics*
  • Lipoprotein Lipase / metabolism
  • Loss of Function Mutation
  • Male
  • Mendelian Randomization Analysis
  • Metabolic Networks and Pathways
  • Middle Aged
  • Prospective Studies
  • Receptors, LDL / genetics*
  • Risk Factors
  • Triglycerides / blood*

Substances

  • Apolipoproteins B
  • Cholesterol, LDL
  • Receptors, LDL
  • Triglycerides
  • Lipoprotein Lipase