Relevance of body weight to apolipoprotein levels in Australian children

Parental obesity as a predictor of childhood overweight/obesity in Australian migrant children

SUMMARY

Obesity levels are increasing disproportionately in immigrant children worldwide. We investigated predictors of immigrant children's obesity status in a well-documented 3-year follow-up study of children at 9 years (n = 1232) and 12 years (n = 628) of age living in inner city areas of Sydney (Australia). The major immigrant groups in this sample were from Europe, the Middle East and SE Asia. Having an obese parent and having either parent or child not being born in Australia and not playing organised sport were predictors of childhood obesity. If either parent was obese compared to non-obese, then the odds ratio for a 9-year-old child of being obese compared to normal weight was 4.9 (95% CI: 3.0-8.0); for 12-year olds the odds ratio was 8.0 (95% CI: 3.6-18). For the survey of 9-years old, a parent born outside Australia or if the child himself was born outside Australia was associated with an almost twofold chance of being obese (OR = 1.8, 95% CI: 1.1-3.0), and not participating in organised sports was significantly associated with childhood obesity. Nine-year olds who did not participate in organised sports outside of school hours were almost twice as likely to be obese (OR = 1.9, 95% CI: 1.2-2.9). When stratified by ethnicity, participation in sports was not related to lower obesity status in children of SE Asian origin. One reason for this could be because SE Asian had very limited participation in sports compared to their counterparts. Accordingly, we believe that health promotion messages to avoid obesity need to be targeted ethnic-specifically.:

Morbidity at elementary school entry differs by sex and level of residence urbanization: a comparative cross-sectional study

Background

Health is vital to a child's learning in school and success in life. Therefore, early physical examination, and follow-up if necessary, would bring parents' attention to their child's health and would likely improve outcomes. The purposes of this study are twofold: to assess the health status of first-graders and to examine the health status differences between sexes, levels of residence urbanization, and quantity of available medical resources.

Methods

This is a comparative descriptive study. Data from the 2002 Student Entry Physical Examination (SEPE) and Student Medical History Inventory (SMHI) were obtained from 203 public and private elementary schools in northern Taiwan where a population of 53,053 students was included. Frequencies, independent sample t test, one-way ANOVA along with Scheff's post hoc test, and Pearson's correlation were conducted using SPSS.

Results

This study showed that 13.7% of students had at least one diagnosed disease from the SMHI reported by parents. Moreover, the SEPE indicated that 79.5% students had at least one health concern. Dental caries, myopia, and obesity were the most prevalent health problems among the first-graders (69.6%, 27.1%, and 9.5%, respectively). Research results show that there were significant differences in the prevalence of dental caries, myopia, and obesity between different sexes and among levels of urbanization. However, the quantity of available medical resources made no significant difference.

Conclusion

Elementary school entry physical examination is an important way to detect students' health problems. It is suggested that school health interventions consider students' health profiles along with their sex and level of urbanization in planning. More research is needed to find the risk factors of the health problems. Additionally, the creation of a school health committee is suggested to implement and evaluate the entry health examination program.

Changes in body composition between 1997 and 2002 among South Australian children: influences of socio-economic status and location of residence

OBJECTIVE

To compare rates of change in South Australian children's body composition between 1997 and 2002 in subsamples based on location of residence and socioeconomic status.

METHODS

Year 6 children from randomly selected South Australian schools in 1997 (32 schools, n=1,423) and 2002 (29 schools, n=992) were compared on: body mass index (BMI), sum of triceps and abdominal skinfolds (skinfold sum) and waist girth. Samples were partitioned into urban (population >20,000) and rural (<10,000) subsamples, and low, medium and high SES. ANCOVA, controlling for boys' decimal age and girls' predicted menarcheal age, was conducted for the whole sample, and where interactions were significant, separately in socio-demographic strata.

RESULTS

Between surveys, there were significant increases in boys' waist girth (p=0.004) and skinfold sum (p=0.007), and girls' BMI (p=0.0005) and skinfold sum (p<0.0001). There were significant interactions of survey year and sociodemographic variables among girls only. While there were no significant changes in anthropometric variables among rural and high SES girls, urban girls increased in skinfold sum (p<0.0001), waist girth (p=0.033) and BMI (p=0.0007). Low (p<0.0001) and medium (p=0.001) SES girls' skinfold sum increased between surveys.

CONCLUSIONS

Secular trends in Australian children's body fatness are continuing. Further, the rates of change in girls are affected by the socio-demographic milieu.

IMPLICATIONS

The development of targeted interventions to combat child obesity will depend on a clearer understanding of how environmental influences on weight status are distributed across the sociodemographic landscape.

New atherosclerosis risk factors in obese, hypertensive and diabetic children and adolescents

In the last few years it has been proved that risk factors for atherosclerosis are present in children and adolescents, and that already at this early age they are connected with anatomic, atheromatous changes in vessels. These changes can not be fully explained as occurring in young people exhibiting traditional risk factors for the disease. The aim of the study was to evaluate levels of several new atherosclerosis risk factors (lipoprotein (a) (Lp(a)), apolipoprotein A-I (Apo A-I), apolipoprotein B (Apo B), homocysteine (Hcy), fibrinogen (FB), tissue plasminogen activator (t-PA) and tissue plasminogen activator inhibitor type 1 (PAI-1)) in children and adolescents with traditional risk factors (obesity, hypertension, diabetes).

MATERIALS AND METHODS

The study group consisted of 285 children and adolescents aged 14.3 years. Children were divided according to their main disease into groups: group A, children with obesity (n=49); group B, children with obesity and coexisting hypertension (n=56); group C, children with hypertension (n=58) and group D, children with diabetes (n=122). Control group consisted of 79 healthy children and adolescents aged 14.1 years. Lp(a), Apo A-I and Apo B levels were estimated by use of immunoturbidimetric methods; total Hcy, FB, t-PA and PAI-1 were estimated by use of immunoenzymatic methods.

RESULTS

Lp(a) level in the total study group was 30 mg/dl and was over twice higher than in control group, 14 mg/dl. Apo A-I level was significantly lower in group A (127.6 mg/dl) and in group B (125.8 mg/dl) versus 135.6 mg/dl in controls. The level of Apo B was significantly higher in total study group (86.2 mg/dl) and in groups A, B and D versus 73.5 mg/dl in controls. Hcy was higher in group B (8 micromol/l) and in group C (9.4 micromol/l) versus 6.2 micromol/l in the control group. The FB level was higher in the total study group (276.7 mg/dl) and in groups A (318.8 mg/dl) and B (322.6 mg/dl) versus 252.8 mg/dl in controls. Significantly higher t-PA level was found in groups A (9 ng/ml) and B (9.7 ng/ml) versus 7.3 ng/ml in controls, and PAI-1 level was significantly higher in the total study group (62.3 ng/ml) and in groups A (73.8 ng/ml), B (78 ng/ml) and C (73 ng/ml) versus 42.4 ng/ml in the control group. Correlation analysis showed significant relationship between body mass index (BMI) and Apo B, Hcy, FB, t-PA and PAI-1. Blood pressure values correlated positively with Hcy. Correlations were verified in multiple regression analysis models: FB and t-PA levels depended on BMI, and Hcy depended on systolic blood pressure.

CONCLUSIONS

(1) Young obese, hypertensive and diabetic patients present significant disturbances in lipid metabolism, regarding mainly total cholesterol, LDL, triglycerides, as well as Lp(a), Apo A-I and Apo B levels. Unfavourable lipid profile is characteristic mainly for children with obesity and accompanying hypertension. (2) Elevated Hcy levels are found in children with hypertension. (3) Elevated FB level and diminished fibrinolytic activity are characteristic of obese children.

Lp(a) and conventional risk profiles predict the severity of coronary stenosis in high-risk hospital-based patients

AIMS

To explore predictive power of Lp(a), of conventional lipoprotein profiles and their carrier proteins, and of biometric measurements, for the presence and severity of angiographically documented coronary disease in high-risk patients, and to compare risk profiles in men and women.

METHODS

We determined coronary artery disease (CAD) risk factors in 1308 Australian Caucasian patients (313 women and 995 men) aged < or =65 years who consecutively underwent coronary angiography.

RESULTS

In univariate analyses of the risk factors, lipid profiles, Lp(a), cigarette smoking, diabetes, hypertension and obesity were all higher in men and women with CAD and changed significantly with the number of significantly diseased vessels (> or =50% luminal obstruction). When stepwise logistic regression analysis was applied, age (OR 1.06, 95% CI: 1.04-1.09), TC/HDL-C (OR 1.29, 95% CI: 1.15-1.45), male gender (OR 2.64, 95% CI: 1.67-4.16), hyperLp(a) (> or =300 mg/L) (OR 2.09, 95% CI: 1.42-3.07), lifetime smoking dose (OR 1.02, 95% CI: 1.01-1.03), diabetes (OR 2.19, 95% CI: 1.14-4.18) and waist/hip ratio (OR 14.53, 95% CI: 1.21-174.90) were predictive of the disease. Both Lp(a) levels and percentage of hyperLp(a) increased linearly with the number of significantly diseased vessels. When the analyses were conducted in men and women separately, hyperLp(a), TC/HDL-C, lifetime smoking dose and age remained as significant predictors in both groups but the waist/hip ratio was only predictive in women.

CONCLUSIONS

As Lp(a) is an independent predictor of the occurrence and extent of coronary stenosis and relevant to treatment options, we suggest that it should be measured routinely in the coronary risk profile assessment of high-risk patients.

The 'price' of Olympic Gold

In 1981 the Commonwealth Government established the Australian Institute of Sport (AIS). The Australian Sports Commission (ASC) which administers the AIS has 2 objectives: (1) excellence in sports performances; and (2) increased participation in sports and sports activities. State-based institutes of sport have also been established with the same or very similar objectives. Federal policy directs the bulk of the ASC budget to elite athlete programs. A smaller proportion goes towards community participation. The official reason is based on the notion of the 'trickle-down' or 'demonstration' effect. That is, a flow-on of benefits to the broader community in the form of increased participation as a direct result of elite sports success. The aims of this study were to determine the (1) spending pattern to elite sports programs for the 5 Olympics 1976/77 to 1995/96, (2) evidence for the two ASC objectives having been met, and (3) expected medal tally at the 2000 Olympic Games. Results show funding (in 1998 dollars), has accelerated from about $1.2 million (1976/77) to $106 million in (1997/98), particularly since the Games were awarded to Sydney. The total amount spent on elite athletes was $0.918 billion. In the period 1980-96 Australia won 25 gold and 115 total Olympic medals. This equates to approximately $37 million per gold and $8 million per medal in general. There was a significant linear relationship between money spent and total medals won. This was also found when all medal types were analysed independently. The predicted medal tally in 2000 (based on the cost per medal and the expenditure towards Sydney) indicates the medal count will be about 14+/-1 gold, 15+/-2 silver and 33+/-4 bronze. Based on our nation's record of international sporting achievement, there is little doubt we have fulfilled the ASC's first objective. Current data on physical activity patterns of Australians suggest the second objective has not been met. Focusing attention on and achieving the first objective does not appear to have any bearing on the second objective. It is time to revisit the notion that elite sporting success leads to greater mass participation as a result of the so-called 'trickle-down' effect.

Does obesity influence foot structure in prepubescent children?

OBJECTIVE

This study examines the relationship between obesity and foot structure in prepubescent children.

DESIGN

Field-based, experimental data on BMI (body mass index) and foot structure were collected for 431 consenting children from 18 randomly selected primary schools.

SUBJECTS

Of the 431 participants, 62 obese (BMI>95th percentile) and 62 non-obese (10th percentile<BMI>90th percentile) children (age = 8.5+/-0.5 y) were selected.

MEASUREMENTS

Height and weight were measured to calculate BMI. Static weight-bearing footprints for the right and left foot of each subject were then taken using a pedograph to calculate the Footprint Angle and the Chippaux-Smirak Index as representative measures of the surface area of the foot in contact with the ground.

RESULTS

A significant difference was found between the Footprint Angle of the obese and non-obese subjects for both the left (t = 3.663; P<0.001) and right (t = 3.742; P<0.001) feet whereby obese subjects displayed a reduced angle. Chippaux-Smirak Index scores were also significantly different for both the left (t = -6.362; P<0.001) and right (t=-5.675; P<0.001) feet between the two subject groups where a greater score for the obese subjects was evident. A decreased footprint angle and an increased Chippaux-Smirak Index are characteristic of structural foot changes that have been associated with compromised foot function.

CONCLUSIONS

Excess body mass appears to have a significant effect on the foot structure of prepubescent children whereby young obese children display structural foot characteristics which may develop into problematic symptoms if excessive weight gain continues. Further investigation into possible consequences, particularly any effects on foot function, is warranted.

Secular trend in body height and weight of Australian children and adolescents

Secular changes in growth and maturation have been well documented in various world populations, with secular increase especially noticeable in the developed countries. To assess the trend in both adult size and tempo of growth we compared the data on stature and body weight obtained in 1992-1993 from 1,804 Melbourne school students aged 5 to 17 with historical data collected from white Australians during the last 100 years. We illustrate the age-dependent trend in stature and body weight by means of regression surfaces. These were constructed by fitting local regression models to historical data and by simple plots showing the overall, and per decade, secular increase in both these measures at peripubertal and adult ages. Because of limited information on sample sizes and variability provided by the historical data, statistical comparisons have been performed only between the present 1992-1993 survey and two earlier independent surveys conducted in 1985 and 1970. The results have shown secular increase in adult stature over the last century, with the rate of increase varying between 0.4 and 2.1 cm/decade in males and 0.01 and 1.6 cm/decade in females. While secular increase in stature has significantly slowed down during the last two decades, the increase in body weight is still continuing at a high rate, and this increase is more pronounced in females. The period of strong secular increase, especially in the tempo of growth, coincided both with the shift toward earlier menarche and the improvement of socioeconomic conditions of the Australian population. The need for further studies to identify factors determining the continuing increase in body weight is emphasized, and caution in using the existing national growth standards for stature and weight is recommended.

Factors associated with obesity in Kuwaiti children

The prevalence of adult obesity in Kuwait is among the highest in the Arab peninsula, and cardiovascular disease, for which obesity is a risk factor, is the leading cause of death. This study reports familial and environmental factors associated with childhood obesity; in addition to adverse effects of obesity on children's serum lipids, lipoproteins, apolipoproteins, insulin, and blood pressure profiles. The authors carried out a pair-matched case-control study including 460 obese (body mass index >90th percentile of the age/sex specific reference value of the National Center for Health Statistics), school children 6 to 13 years old matched by age and gender to 460 normal weight controls. We ascertained obese children in a cross-sectional survey of a representative sample of 2400 school children selected from 20 schools by multistage stratified random sampling. Biochemical variables and blood pressure were adversely affected in obese children. The conditional logistic regression analysis showed that family history of obesity, and diabetes mellitus, respiratory and bone diseases in child were significant associated factors with obesity after adjusting for social and behavioural factors. Physical activity and parental social class were not significant. We recommend early preventive measures with emphasis on families in which one or both parents are overweight.

Apolipoprotein screening in Australian children: feasibility and the effect of age, sex, and ethnicity

OBJECTIVE

(i) To evaluate the feasibility of detecting adverse lipid profiles in schoolchildren by measuring capillary dried blood spot apolipoprotein levels, and (ii) to assess the effect of age, sex and ethnicity on apolipoprotein levels.

DESIGN

We measured capillary dried blood spot apolipoproteins B and A-I (apo B and apo A-I); assessed levels in relation to age, sex and ethnicity; and recalled children with elevated levels for a full lipid profile measurement.

PARTICIPANTS AND SETTING

6992 children (3501 boys and 3491 girls), aged 5-13 years, from schools in eastern Sydney, 1991-1995.

MAIN OUTCOME MEASURES

Capillary blood levels of apolipoproteins B and A-I, and serum total cholesterol level.

RESULTS

Of the 6951 children who provided an adequate fingerprick blood sample, we recalled 1465 children (21.1%) (640 boys [43.7%] and 825 girls [56.3%]) with elevated apo B levels and/or apo B:apo A-I ratios for further testing, either by us or by their family doctor (overall estimated compliance rate up to 70%). Among the 458 children who returned to us, there was a 90% positive predictive value for a total cholesterol level of over 4.5 mmol/L in those with both elevated apo B levels and high apo B:apo A-I ratios. Girls had higher apo B levels and apo B:apo A-I ratios than boys (P < 0.00001 for both), and in both sexes there was a trend downwards for apo B and upwards for apo B:apo A-I ratio over the age range tested, but levels were relatively stable between the ages of 6 and 10 years. Indian children (1.5% of the screened population) had the highest apo B levels, followed by white children (71.1%); Asian children (9.2%) had the lowest (P < 0.00001 compared with Indian and white children).

CONCLUSIONS

The high positive predictive value of capillary blood apolipoprotein levels for an adverse lipid profile in children suggests that measuring apolipoprotein levels by this method is a useful initial approach to cardiovascular risk assessment.

Determinants of the kinetics of very low-density lipoprotein apolipoprotein B-100 in non-obese men

1. Apolipoprotein B-100 (ApoB) is the principal structural and functional protein of the pro-atherogenic lipoproteins. Elevated plasma apoB is an independent risk factor for coronary artery disease. In the present study we aimed to assess the factors that determine the kinetics of apoB in the very low-density lipoprotein (VLDL) in healthy men. 2. We studied 17 non-obese men who were consuming an ad libitum diet and had the following characteristics: mean (+/-SD) age 45.5 +/- 9.7 years, body mass index (BMI) 25.1 +/- 1.4 kg/m2, waist:hip ratio 0.91 +/- 0.04, serum cholesterol 5.2 +/- 0.6 mmol/L, triglycerides 1.08 +/- 0.53 mmol/L and high-density lipoprotein-cholesterol 1.24 +/- 0.31 mmol/L. Daily dietary intake was as follows: total fat 76 +/- 26 g, carbohydrate 238 +/- 67 g, protein 103 +/- 33 g and alcohol 20 +/- 16 g. 3. The kinetics of VLDL ApoB were studied using a primed, constant infusion (1 mg/kg per h) of 1-[13C]-leucine over 8 h with measurement of isotopic enrichment of ApoB using gas chromatography/mass spectrometry. The fractional turnover rate of VLDL ApoB was estimated using a monoexponential function. The mean (+/-SD) absolute hepatic secretion rate (ASR) of ApoB was 8.5 +/- 4.6 mg/kg per day and the fractional catabolic rate (FCR) was 7.9 +/- 5.6 pools/day. The ASR was significantly correlated with the waist:hip ratio (r = 0.60; P = 0.04), but not with age, BMI, weight or nutrient intake. The FCR was significantly and inversely correlated with plasma triglycerides (r = -0.53; P = 0.03) and alcohol intake (r = -0.48; P = 0.05). 4. In conclusion, the hepatic secretion of VLDL ApoB in nonobese, healthy men is primarily determined by the waist:hip ratio, a measure of visceral fat. This is consistent with the hypothesis that the rate of lipid substrate supply in the liver regulates the output of ApoB. The fractional catabolism of VLDL ApoB may, however, be inversely related to alcohol intake and appears to determine the plasma concentration of triglycerides.

Prediction of obesity in children at 5 years: a cohort study

OBJECTIVE

To examine determinants of moderate and severe obesity in children at 5 years of age.

METHODOLOGY

A prospective cohort of mothers were enrolled at first antenatal visit, and interviewed shortly after delivery, at 6 months and 5 years. Detailed health, psychological and social questionnaires were completed at each phase by mothers, and child health questionnaires at 6 months and 5 years. At 5 years 4062 children were assessed physically, the Peabody Picture Vocabulary Test administered and mothers completed a modified Child Behaviour Checklist. Moderate obesity was defined as BMI between 85th and 94th percentiles inclusively, and severe obesity as a BMI greater than the 94th percentile.

RESULTS

Independent predictors of severe obesity at 5 years were birthweight, female gender, maternal BMI and paternal BMI. Moderate obesity at 5 years was predicted by birthweight, paternal BMI and sleeplessness at 6 months, while small for gestational age (SGA) status and feeding problems at 6 months were protective factors for moderate obesity. Obesity was not associated with problems of language comprehension or behaviour.

CONCLUSIONS

Findings of this study suggest that biological rather than psychosocial factors are the major determinants of obesity at 5 years.