IMPACT OF GENDER, APOLIPOPROTEIN-E PHENOTYPES, AND DIET ON SERUM-LIPIDS AND LIPOPROTEINS IN INFANCY

Objective: To determine the influence of gender, apolipoprotein E phen otypes, and diet on the interindividual variances in serum lipid and l ipoprotein concentrations in children at 7 and 13 months of age. Study design: Prospective randomized intervention trial. Half of 1062 famil ies with 7-month-old infants received dietary and lifestyle counseling aimed at partially replacing saturated fat with mono-and polyunsatura ted fat and reducing exposure to other known atherosclerosis risk fact ors, This study comprises all trial children who at 8 months of age re ceived, in addition to solid food, only breast milk or only formula (N = 553). Forward stepwise multiple regression analysis was used in the evaluation of the contributions of gender, apolipoprotein E phenotype , and diet. Results: Apolipoprotein E phenotypes, gender, and milk typ e provided independent information concerning serum lipid values at 7 and 13 months of age (three-way ANOVA, p < 0.01). At 7 months, milk ty pe was the most significant predictor of total, non-high-density lipop rotein and high-density lipoprotein cholesterol and apolipoprotein B a nd Al concentrations. At 13 months when the effects of gender (5%) and apolipoprotein E type (5%) were excluded, diet predicted only 2% of t he variance in serum cholesterol concentration. The apolipoprotein E t ype predicted 8% of the variance in non-high-density lipoprotein chole sterol concentration and 7% of the variance in apolipoprotein B concen tration (p < 0.001), together explaining only 3% of the variance in se rum high-density lipoprotein cholesterol and apolipoprotein Al concent rations. Conclusions: At 7 months of age diet is an important predicto r of serum lipid and lipoprotein concentrations. At the age of 13 mont hs the apolipoprotein E phenotype significantly predicts the concentra tions of serum non-high-density lipoprotein cholesterol and apolipopro tein B. However, at both ages apolipoprotein E phenotype, gender, and diet together explain only from 1.4% to 15.5% of the variance in serum lipids and apolipoproteins, suggesting that other, presumably genetic , factors are major determinants.