High Serum Apolipoprotein E Determines Hypertriglyceridemic Dyslipidemias, Coronary Disease and ApoA‐I Dysfunctionality

AbstractThe relevance of serum apolipoprotein E (apoE) levels to two hypertriglyceridemic dyslipidemias has not been clarified. We explored, in a cross‐sectional (and short‐term prospective) evaluation, the independent relationship of serum apoE to the atherogenic dyslipidemia, hypertriglyceridemia with elevated apoB (HtgB) and to apoA‐I dysfunctionality, previously shown in Turkish adults to be independent of apoE genotype. Serum apoE concentrations were measured by immunonephelometry in 1,127 middle‐aged adults. In multivariable regression analysis, apoE concentrations showed log‐linear associations with apoB and apoA‐I levels, waist circumference, independent of C‐reactive protein (CRP), homeostatic model assessment (HOMA) index and other confounders. The likelihood of atherogenic dyslipidemia and of HtgB roughly tripled per 1‐SD increment in apoE concentrations, additively to apoE genotype, HOMA, apoA‐I, CRP concentrations and waist circumference; yet apoA‐I, protective against atherogenic dyslipidemia, appeared to promote HtgB, a finding consistent with apoA‐I dysfunctionality in this setting. Each 1‐SD increment in the apoE level was moreover, associated in both genders with MetS (at OR 1.5), after adjustment for sex, age, apoB, apoA‐I and CRP, or for apoE genotypes. Circulating apoE predicted in both genders age‐adjusted prevalent and incident coronary heart disease (CHD), independent of apoE genotype and CRP (OR 1.32 [95 % CI 1.11; 1.58]). To conclude, in a general population prone to MetS, elevated apoE concentrations are strongly linked to HtgB and atherogenic dyslipidemia, irrespective of apoE genotype, are associated with MetS and CHD. Excess apoE reflects pro‐inflammatory state and likely autoimmune activation.