Recommendations for dietary intervention in the prevention and treatment of hyperlipidaemia in childhood. The Dietitians' Association of Australia and the Australian College of Paediatrics

Relevance of body weight to apolipoprotein levels in Australian children

OBJECTIVES

To assess weight and apolipoprotein profiles in a representative sample of primary school children.

PARTICIPANTS AND SETTING

1543 children (936 girls and 607 boys) aged 6-11 years from schools in the Eastern Sydney Area Health Service region in 1994.

METHODS

We measured body mass index (BMI) and capillary blood apolipoprotein (apo) B and A-I levels (the carrier proteins for low and high density lipoprotein cholesterol, respectively) as well as lipoprotein (Lp) (a). We related BMI levels to those documented in the 1985 Australian Council on Health, Physical Education and Recreation (ACHPER) survey of school children.

RESULTS

Compared with the ACHPER distribution, BMI was increased in the boys but not in the girls; 16.8% of boys were above the 90th percentile of the ACHPER distribution (P = 0.003) and only 6.5% were below the 10th percentile (P = 0.046). There were 45 boys (7.4%) and 53 girls (5.7%) with BMIs above the 95th percentile who were, by definition, obese. They had highly significant increases in apo B (P = 0.003) and apo B: apo A-I ratio (P = 0.0001) compared with children in the normal BMI range (10th-90th percentiles); and 20% of the population, including the obese group, also had Lp(a) levels greater than 300 mg/L. The results in children aged 10 and 11 years were not different from those of the whole group, consistent with an absence of possible confounding effects due to early puberty or smoking.

CONCLUSIONS

There was an increase in weight relative to height in boys aged 6-11 years in eastern Sydney, compared with the 1985 ACHPER survey. In both boys and girls with the highest BMI category, levels of apo B and the apo B: apo A-I ratio were significantly increased. As these apolipoprotein changes are correlated closely with early onset atherogenesis and are correctable, their identification offers prospects for prevention.

Serum lipids and apolipoproteins from 1 to 15 years: changes with age and puberty, and relationships with diet, parental cholesterol and family history of ischaemic heart disease

We describe the pattern of change for serum lipids and apolipoproteins from 1 to 15 years of age in a cohort of 128 children, supplemented with 215 children from 11 years of age and 243 at 13 years of age. Total cholesterol (TC) decreased after infancy, increased in early puberty and then decreased to 15 years of age. Reciprocal changes in high (HDLC) and low (LDLC) density lipoprotein cholesterol occurred during each interval, with HDLC increasing from 13 to 15 years in both sexes. The correlation for TC between children of both sexes and mothers and fathers varied from 0.1 to 0.28 at 2-13 years. At 15 years of age the correlation between mothers: daughters increased to 0.31, decreased to 0.19 for fathers: daughters, but no association was present between either parent and their sons. There were no differences in mean lipid values for the sample grouped according to the extent of family history of early ischaemic heart disease (before 60 years of age). There were few significant associations between serum lipids, energy and nutrients. At 15 years of age inverse associations were present between TC and energy, protein, sugar, starch and fibre intakes, and a positive association with total fat intake.