Apolipoprotein E4 phenotype increases non-fasting serum triglyceride concentration in infants — the STRIP study

As genetically determined apolipoprotein E (apo E) phenotypes influence serum cholesterol concentration, we analysed whether serum triglyceride values are also affected by the apo E phenotypes in infants. Non-fasting serum triglyceride values were measured in 7- and 13-month-old participants in the STRIP project, a randomised, prospective trial aimed at reducing childrenʹs exposure to known atherosclerosis risk factors (n=1062). The mean±S.D. non-fasting serum triglyceride concentrations in 7-month-old infants with apo E4/4 (n=36), E3/4 (n=209), E3/3 (n=412), and E2/3 (n=66) were 2.05±1.24, 1.81±0.90, 1.63±0.90, and 1.71±0.83 mmol/l, respectively. Triglyceride concentrations were higher in infants with apo E4/4 or 3/4 than in those with apo E3/3 (P-value for difference 0.01 and 0.009, respectively). The apo E phenotype similarly influenced non-fasting serum triglyceride concentrations at the age of 13 months. The differences in serum triglyceride values in apo E4+ infants (apo E3/4 and 4/4 infants combined) and apo E4− infants (apo E2/3 and 3/3 infants combined) occurred independently of the relative weight of the infant, milk type used at 7 months of age (breast milk or formula), and time elapsed from the previous meal. To conclude, apo E phenotypes regulate non-fasting serum triglyceride values in healthy infants. Apo E3/4 and apo E4/4 predispose infants to higher values than apo E3/3 phenotype, suggesting that the 4 allele may increase atherosclerosis risk also via itʹs effect on postprandial triglyceride metabolism.