Serum cholesterol and serum triglyceride levels in Australian adolescent males

Age- and Gender-Specific Reference Intervals for Fasting Blood Glucose and Lipid Levels in School Children Measured With Abbott Architect c8000 Chemistry Analyzer

Reference intervals for pubertal characteristics are influenced by genetic, geographic, dietary and socioeconomic factors. Therefore, the aim of this study was to establish age-specific reference intervals of glucose and lipid levels among local school children. This was cross-sectional study, conducted among Saudi school children. Fasting blood samples were collected from 2149 children, 1138 (53%) boys and 1011 (47%) girls, aged 6 to 18 years old. Samples were analyzed on the Architect c8000 Chemistry System (Abbott Diagnostics, USA) for glucose, cholesterol, triglycerides, HDL and LDL. Reference intervals were established by nonparametric methods between the 2.5th and 97.5th percentiles. Significant differences were observed between boys and girls for cholesterol and triglycerides levels in all age groups (P < 0.02). Only at age 6-7 years and at adolescents, HDL and LDL levels were found to be significant (P < 0.001). No significant differences were seen in glucose levels except at age 12 to 13 years. Saudi children have comparable serum cholesterol levels than their Western counterparts. This may reflect changing dietary habits and increasing affluence in Saudi Arabia. Increased lipid screening is anticipated, and these reference intervals will aid in the early assessment of cardiovascular and diabetes risk in Saudi pediatric populations.

Age- and gender-specific reference intervals for serum lipid levels (measured with an Advia 1650 analyzer) in school children

BACKGROUND

Due to the lack of country-specific norms in Saudi Arabia, age- and gender-specific lipid reference intervals are needed to be established for Saudi children.

METHODS

Blood samples were collected from 1168 children aged 6-16 years: 500 boys (43%) and 668 girls (57%), and were analyzed for cholesterol, high-density lipoprotein (HDL) and low-density lipoprotein (LDL). Reference intervals were established by calculating the mean and the 2.5th and 97.5th percentiles.

RESULTS

There were significant differences between boys at each Tanner stage with respect to cholesterol (P < 0.001); and HDL (P < 0.0001) but not LDL (P < 0.06) among girls. There were significant differences between boys and girls during puberty with respect to cholesterol (P < 0.0001), HDL (P < 0.0001), and LDL (P < 0.001). There was a significant positive correlation between total cholesterol levels, LDL and HDL levels at all Tanner stages in both genders. In girls, the only significant inverse correlation was at stage I (r=-0.243, P= 0.001); there was no significant correlation at other stages.

CONCLUSIONS

Unlike children in other developing countries, Saudi children do not have lower serum cholesterol than their Western counterparts. These findings reflect changing dietary habits and increasing affluence in Saudi Arabia. These reference intervals may be used to aid in the early assessment of cardiovascular risk in Saudi pediatric populations.

Coronary heart disease risk factors in male adolescents, with particular reference to smoking and blood lipids

PURPOSE

To examine coronary heart disease (CHD) risk factors, particularly blood lipids and smoking, in adolescent boys in the Sydney Metropolitan area, and to investigate possible differences between boys from English-speaking (ESB) and non-English-speaking backgrounds (NESBs).

METHODS

Male volunteers aged 15-18 years were recruited from the senior years of four secondary schools in different geographical areas of Sydney. Body mass index (BMI), waist-hip ratio (WHR), blood lipids, and percent body fat were measured. Behavioral variables were estimated by questionnaire.

RESULTS

A total of 110 boys were recruited; 74% were from an ESB. Mean WHR (0.836 +/- 0.045), waist circumference (80.6 +/- 9.4 cm), and percent body fat (21.0 +/- 6.3) were similar across age groups. Atherogenicity of the lipid profile, as measured by the ratio of total cholesterol to high-density lipoprotein cholesterol (TC:HDL-C), was lower in boys aged 15 years than in any other age group (p < .05). TC:HDL-C was strongly associated with BMI (r = .57; p < .0001) and WHR (r = .35; p < .01). Smokers had higher BMI, were less active and had lower HDL-C (p < .001) and higher TC:HDL-C (p < .0001) than nonsmokers. Smoking, even of short duration, and quite moderate consumption of cigarettes (6/day) were associated with a deterioration of the lipid profile. Boys from NESBs had a higher degree of risk in all of the factors examined.

CONCLUSIONS

Regular smoking of short duration has an appreciable impact on lipid and lipoprotein concentrations in this sample of Australian adolescent boys. Boys from an NESB appear to be at greater risk of developing CHD in later life.

Plasma cholesterol and other cardiac risk factors in adolescent girls

The aim was to examine the effects of smoking, physical activity, and body mass on total cholesterol and high density lipoprotein cholesterol (HDL-C) in adolescent schoolgirls in Sydney, Australia. Body mass index (BMI) and waist to hip ratio (WHR) were determined in 144 girls aged 15 to 18 years. Total cholesterol (TC) and HDL-C were estimated on fingerprick blood and behavioural variables assessed by questionnaire. Prevalence of overweight (> 90th centile for BMI) was less in Australian adolescents than reported from the USA. Smokers had lower total cholesterol than non-smokers; this was partly explained by a lower HDL-C in the smokers. Physical activity was associated with a less atherogenic TC/HDL-C ratio. Girls with BMI > 90th centile had higher mean TC/HDL-C and apoprotein B than the group as a whole but those > 90th centile for WHR did not.

Reflotron cholesterol measurements in 1112 Australian children aged 10-12 years

OBJECTIVE

To study the distribution of blood cholesterol concentration in a sample of Western Australian schoolchildren.

DESIGN

The Reflotron dry-chemistry system (Boehringer Mannheim, Germany) was used to measure cholesterol in finger-prick blood samples obtained from Year 6 children aged 10-12 years attending government schools in metropolitan Perth. Recruitment methods ensured that children from different socioeconomic strata were represented.

PARTICIPANTS

For the 1239 children enrolled in Year 6 in 30 government schools, parental consent to participate was obtained for 1144; of these cholesterol concentration was measured in 1112.

RESULTS

The measurement method proved practicable and was generally well accepted. Cholesterol levels were somewhat lower than those obtained using a laboratory reference method and a bias, relative to national quality assurance standards, was estimated to be -0.32 mmol/L. Mean cholesterol level in boys (4.28 mmol/L, SD 0.69) was not significantly different from that in girls (4.35 mmol/L, SD 0.72). Allowing for measurement bias, 52% of boys and 57% of girls had cholesterol levels exceeding the National Heart Foundation's designated "desirable" level of 4.5 mmol/L for children.

CONCLUSIONS

The distribution of cholesterol levels in Australian children compares unfavourably with distributions in children in countries with low rates of cardiovascular disease and indicates a need for widespread, appropriate diet and lifestyle changes.

Risk factors for coronary heart disease among Jerusalem schoolchildren: preliminary findings

The presence of risk factors for cardiovascular diseases were investigated in 7- and 11-year-old schoolchildren (808 subjects). Data analysis was performed according to sex, age, and country of origin of the father. The following variables were investigated: weight, height, total plasma cholesterol (TCH), high density lipoprotein cholesterol (HDL), plasma triglycerides, and systolic and diastolic blood pressure. Significant differences were found between sex, age, and origin groups for most variables. The prevalence of hypercholesterolemia (greater than 180 mg/dl) varied between 9.6 and 14.1%, in the different sex and age groups, and that of low HDL cholesterol (less than 40 mg/dl), 6.8-12.1%. Elevated systolic blood pressure (greater than 130 mm Hg) was found in 4.4-6.7% of the 7-year-old children, and in 13,4-18.6% of the 11 year-olds. Elevated diastolic blood pressure (greater than 85 mm Hg) was found predominantly in the 11-year-old children, 6.2-9.1%. These findings demonstrate the necessity to initiate health programs related to prevention of cardiovascular diseases in childhood.

Sex, social status and ethnic origin in relation to coronary heart disease risk factors in Adelaide schoolchildren

The relationship of several Coronary Heart Disease risk factors to sex, social status and ethnic background was studied in a sample of 539 grade-5 students (10-year-olds) in eight volunteer primary schools in Adelaide. The risk factors examined were: obesity (sum of four skinfolds); blood pressure; fitness (physical work capacity (PWC) 170/kg); and plasma cholesterol, triglyceride, and high density lipoprotein cholesterol levels. Social status differences were negligible for all risk factors. However, differences between the sexes, and between ethnic groups, were marked, particularly in relation to fitness and obesity. Girls carried significantly more body fat than boys, although their height and weight were similar; they were less fit. Their plasma lipid levels and blood pressure, on the other hand, were very similar to those for boys. Values for children whose parents were born in Australia and the United Kingdom were similar for all risk factors. However, children of both sexes whose parents were born in Italy and Greece were fatter and less fit.U

The 1977 Busselton children's survey

A health survey of 551 high school students in the coastal town of Busselton, Western Australia, was undertaken in November, 1977. Physical measurements showed that approximately 17% of the boys and 24% of the girls were overweight (115% or more of their standard weight for height and age). Blood pressures ranged from 108/64 mmHg at 13 years to 129/70 mmHg at 17 years for boys, and 109/63 mmHg to 116/66 mmHg for girls of the same age group. Fasting plasma glucose, cholesterol and triglyceride values were also obtained. Twenty-seven per cent of the girls and 17% of the boys were regular smokers, a habit often acquired by the age of 12 years. Most of the children watched television from two to four hours daily during the week, and for longer periods at weekends. Although most had satisfactory levels of physical fitness, there was a trend towards poor performance in overweight children, and there was a significant decrease in participation in regular sports by the older teenagers.

Nutrient consumption patterns of families in Busselton, Western Australia

Nutrient consumption data were obtained from 211 members of 41 families living in the coastal town of Busselton, Western Australia. It was found that food consumption patterns were similar in boys and girls up to the age of 11 years. After that, as expected, males consumed more food than females. There was a general tendency for daily kilojoule intakes to be considerably less than the Australian Dietary Allowances for all age groups with the exception of males aged from 35 to 55 years. There was a significant prevalence of obesity in the subjects who were studied, particularly in the older groups of both sexes. The results suggest that, in the older adult groups, failure to make concessions to decreased levels of physical activity by modifying appetite and customary eating practices is a major factor which contributes to obesity.

Serum cholesterol and triglyceride levels in Norwegian adolescent school children

The frequency distribution of serum cholesterol and triglycerides in 172 boys and 232 girls, 13--16 years, from four elementary schools in Oslo has been determined. The cholesterol values were significantly higher for girls 15--16 years than for boys of the same age group. In the case of triglycerides boys 15--16 years had significantly higher values than boys 13--14 years. Otherwise no statistically significant differences with regard to sex and age were observed. The 85th percentiles have been suggested as appropriate upper normal limits. In all groups the 85th percentile for plasma cholesterol was slightly below 6 mmol/l. The corresponding plasma triglyceride value was below 2 mmol/l.

Serum cholesterol and triglyceride levels in 3,446 children from a biracial community: the Bogalusa Heart Study

Serum lipid profiles of 3,446 (91% of population) children, ages 5-14 years, were determined in a biracial community (Bogalusa, Louisiana) as part of a program investigating the early natural history of atherosclerosis. Black children had significantly higher mean levels of serum cholesterol than white children (170 mg/dl vs 162 mg/dl, P less than 0.0001). On the other hand, significantly lower levels of triglycerides were found in blacks than in whites (61 mg/dl vs 73 mg/dl, P less than 0.0001). Girls had higher levels of triglycerides than boys in both races (blacks, 64 mg/dl vs 59 mg/dl, P less than 0.001; whites, 77 mg/dl vs 69 mg/dl, P less than 0.001). The racial differences in serum cholesterol and triglyceride levels were even more apparent at the 95th percentile. The serum cholesterol level remained relatively constant in all children until ages 11 and 12 years, after which a slight reduction occurred. This reduction was more pronounced in boys than in girls. In contrast, a significant increase in the level of triglycerides with age was observed in all children except black girls, the increasing slope being most pronounced in white girls.