Longitudinal changes of serum lipid and apoB levels in a newborn-infant cohort

Abstract

Longitudinal changes in serum apoB levels in relation to serum lipid levels were determined in a subset ( n = 30) of a newborn-infant cohort selected from infants ( n = 440) of Bogalusa, Louisiana who were born between January 1, 1974 and June 30, 1975. Serum total cholesterol, triglycerides, β + pre-β-lipoprotein cholesterol and apoB levels were measured at birth, 6 mo, 1 yr, 2 yr, and 3 yr of age. The mean ± SD, mg/dl, levels of these variables increased dramatically ( p < 0.0005) from birth to 6 mo (Total cholesterol: 65.0 ± 15.7 versus 136.3 ± 27.4; triglycerides: 32.9 ± 18.9 versus 82.3 ± 28.9; β + pre-β-lipoprotein cholesterol: 31.8 ± 9.1 versus 87.3 ± 25.7; apoB: 20.8 ± 5.3 versus 49.0 ± 13.5). On the other hand, the ratio of apoB to β + pre-β-lipoprotein cholesterol at birth was significantly higher than at 6 months of age (0.69 ± 0.24 versus 0.58 ± 0.12, p < 0.0005). None of the variables changed significantly between 6 mo and 3 yr of age except the increase in serum total cholesterol level from yr 2 to yr 3 (142.6 ± 26.6 versus 156.4 ± 23.0, p < 0.01). A tigh intra-child year to year correlation for serum apoB was noted beginning at 6 mo of age ( r = 0.67, p < 0.0001); while the apoB levels were proportional to β + pre-β-lipoprotein cholesterol levels in some children, others had varied levels of apoB in relation to cholesterol carried by this apoprotein. The fact that apoB levels persist beginning at 6 mo of age and that we are beginning to observe interindividual differences in levels of cholesterol carried by this apoprotein may have clinical implications for coronary artery disease.