BACKGROUND: Routine apolipoprotein (apo) measurements for cardiovascular disease 
(CVD) are restricted to apoA-I and apoB. Here, the authors measured an 
unprecedented range of apolipoproteins in a prospective, population-based study 
and relate their plasma levels to risk of CVD.
OBJECTIVES: This study sought to measure apolipoproteins directly by mass 
spectrometry and compare their associations with incident CVD and to obtain a 
system-level understanding of the correlations of apolipoproteins with the 
plasma lipidome and proteome.
METHODS: Associations of 13 apolipoproteins, 135 lipid species, and 211 other 
plasma proteins with incident CVD (91 events), defined as stroke, myocardial 
infarction, or sudden cardiac death, were assessed prospectively over a 10-year 
period in the Bruneck Study (N = 688) using multiple-reaction monitoring mass 
spectrometry. Changes in apolipoprotein and lipid levels following treatment 
with volanesorsen, a second-generation antisense drug targeting apoC-III, were 
determined in 2 human intervention trials, one of which was randomized.
RESULTS: The apolipoproteins most significantly associated with incident CVD 
were apoC-II (hazard ratio per 1 SD [HR/SD]: 1.40; 95% confidence interval [CI]: 
1.17 to 1.67), apoC-III (HR/SD: 1.38; 95% CI: 1.17 to 1.63), and apoE (HR/SD: 
1.31; 95% CI: 1.13 to 1.52). Associations were independent of high-density 
lipoprotein (HDL) and non-HDL cholesterol, and extended to stroke and myocardial 
infarction. Lipidomic and proteomic profiles implicated these 3 very-low-density 
lipoprotein (VLDL)-associated apolipoproteins in de novo lipogenesis, glucose 
metabolism, complement activation, blood coagulation, and inflammation. Notably, 
apoC-II/apoC-III/apoE correlated with a pattern of lipid species previously 
linked to CVD risk. ApoC-III inhibition by volanesorsen reduced plasma levels of 
apoC-II, apoC-III, triacylglycerols, and diacylglycerols, and increased apoA-I, 
apoA-II, and apoM (all p < 0.05 vs. placebo) without affecting apoB-100 (p = 
0.73).
CONCLUSIONS: The strong associations of VLDL-associated apolipoproteins with 
incident CVD in the general community support the concept of targeting 
triacylglycerol-rich lipoproteins to reduce risk of CVD.