Biomedical consequences of elevated cholesterol-containing lipoproteins and apolipoproteins

AimsTo provide a comprehensive evaluation of the biomedical effects of circulating concentrations of cholesterol-containing lipoproteins and apolipoproteins. Methods and ResultsNuclear magnetic resonance (NMR) spectroscopy was used to measure the cholesterol content of high density (HDL-C), very low-density (VLDL-C), intermediate-density (IDL-C), and low-density (LDL-C) lipoprotein fractions; apolipoproteins Apo-A1 and Apo-B; as well as total triglycerides (TG), remnant-cholesterol (Rem-chol) and total cholesterol (TC). The causal effects of these exposures were assessed against 33 cardiovascular as well as non-cardiovascular outcomes using two-sample univariable and multivariable Mendelian randomization. We observed that most cholesterol containing lipoproteins and apolipoproteins affected coronary heart disease (CHD), cIMT, carotid plaque, CRP and blood pressure. Through MVMR we showed that many of these exposures acted independently of the more commonly measured blood lipids: HDL-C, LDL-C and TG. We furthermore found that HF risk was increased by higher concentrations of TG, VLDL-C, Rem-Chol and Apo-B, often independently of LDL-C, HDL-C or TG. Finally, a smaller subset of these exposures could be robustly mapped to non-CVD traits such as Alzheimers disease (HDL-C, LDL-C, IDL-C, Apo-B), type 2 diabetes (VLDL-C, IDL-C, LDL-C), and inflammatory bowel disease (LDL-C, IDL-C). ConclusionThe cholesterol content of a wide range of lipoprotein and apolipoproteins affected measures of atherosclerosis and CHD, implicating subfractions beyond LDL-C. Many of the observed effects acted independently of LDL-C, HDL-C, and TG, supporting the potential for additional, non-LDL-C, avenues to disease prevention.