The effect of diet on blood lipids has been under intensive study during recent decades. However, diet in the context of the hyperapobetalipoproteinemia (hyperapoB) phenotype has received less attention. The hyperapoB phenotype is commonly encountered in patients with premature coronary heart disease. It is defined as a combination of an increased concentration of apolipoprotein B (apo B), a normal concentration of LDL cholesterol (LDL-C), and as a result, a low LDL-C/apo B ratio. We studied the associations between diet and blood lipids in a cohort of 534 children and young adults 9 to 24 years old. The ratio of polyunsaturated to saturated fats (P/S ratio) correlated (r=-0.19, P
Association of serum lipids with metabolic control and diet were studied in 72 young subjects with insulin-dependent diabetes mellitus (IDDM). Data on food consumption were collected by the 48-h recall method. Glycosylated haemoglobin (Hb) A1 was used as a measure of metabolic control. There were no differences between males and females in the mean values for serum total cholesterol (TC, 4.5 and 4.9 mmol/l, respectively), low density lipoprotein cholesterol (LDL-C, 2.7 and 3.0 mmol/l), high density lipoprotein cholesterol (HDL-C, 1.3 and 1.4 mmol/l), or serum triglycerides (TG, 1.1 and 1.0 mmol/l). Diabetic subjects who were in better metabolic control (HbA1 or = 10.5%) had lower TC and TG values and a higher HDL-C/TC ratio. HbA1 level and intake of saturated fatty acids were positively associated with serum TC and LDL-C values and explained 14% and 15% of the variation in TC and LDL-C, respectively. HbA1 level and insulin dose per kg of body weight were positively associated with serum TG values and explained 30% of the variation in TG. Serum TC and LDL-C levels of young subjects with IDDM could be lowered by improving their metabolic control and decreasing their saturated fatty acid intake.
The concentrations of apolipoproteins A-I and B were determined in 1,341 3- to 18-year-old children and adolescents from five urban and 12 rural communities. The analyses were made with radial immunodiffusion. The mean concentrations (+/- S.D.) of apo A-I and apo B were 152 +/- 25 and 94 +/- 22 mg/100 ml, respectively. 3-year-old children had the highest apo B levels which then decreased with advancing age in both sexes. Boys tended to have lower levels of apo B than girls. Apo A-I concentration was significantly higher in the 9- and 12-year-old boys than in the other age groups but showed no age-bound trend in girls. The apo A-I to apo B ratio increased with age in both sexes. The concentration of apo A-I was significantly lower, and that of apo B higher, in children living in eastern Finland in comparison with those from the western part of the country. This difference and a higher HDL-cholesterol to apo A-I ratio in both sexes in eastern Finland may be associated with the regional differences in the prevalence of coronary heart disease in this country.
The effect of physical activity on serum total and low-density lipoprotein cholesterol concentrations varies with apolipoprotein E phenotype in male children and young adults: The Cardiovascular Risk in Young Finns Study.
Apolipoprotein E (apo E) determines serum total (TC) and low-density lipoprotein (LDL-C) cholesterol concentrations and is thus associated with coronary heart disease (CHD) risk. We studied if the effect of physical activity (PA) on serum TC and LDL-C concentrations varies with apo E phenotype in a population-based sample of children and young adults with regular PA. The study cohort consisted of subjects aged 9, 12, 15, 18, 21, and 24 years in 1986 (N = 1,498) participating in a large multicenter study of cardiovascular risk factors in children and young adults. Serum lipid concentrations were determined enzymatically, and apo E phenotypes by isoelectric focusing and immunoblotting. The composition of the diet was determined by a 48-hour recall method, and a PA index was calculated on the basis of frequency, intensity, and duration of activity assessed by a questionnaire. LDL-C (P = .0082), TC (P = .014), and the high-density lipoprotein cholesterol (HDL-C)/TC ratio (P = .0004) responses to exercise varied with apo E phenotype. The effect of PA on LDL-C, TC, or HDL/TC was not found in apo E phenotype E4/4. A moderate inverse effect of PA on TC and LDL-C and a positive effect on HDL/TC was found in subjects with E4/3 and E3/3 phenotypes. Similar but stronger associations were found between these variables within the group of E3/2 males. The effect of PA on serum lipid levels was strongest within the phenotype E3/2. These associations were not explained by dietary habits. Apo E phenotype partly determines the effect of PA on serum TC and LDL-C in Finnish male children and young adults with regular PA.
Children in the eastern part of Finland have higher serum total and low-density lipoprotein (LDL) cholesterol levels than children in the western part of the country. This is consonant with the high mortality rate for coronary heart disease in eastern Finland. Eastern and western Finns are assumed to have different geographic origins; because of this we divided into groups 630 newborns and 3554 children and adolescents according to their grandparents' birthplace, which, in Finland, reflect the origins of the children. No differences in serum lipid levels were found in the newborns but in the 3- to 18-year-old children the differences in mean serum total and LDL cholesterol levels were accentuated by this division. Boys with grandparents from the extreme eastern part and those with grandparents from the western part of the country showed the greatest differences. Prepubescent boys 3 to 12 years old living in the west but with grandparents from the east had total and LDL cholesterol levels similar to those of boys living in and descended of grandparents from the east, despite their diet being of the western type. Thus, although diet is known to be a major determinant of serum cholesterol level, genetic factors also seem to play a role.