Secular Trends of Obesity Prevalence in Urban Chinese Children from 1985 to 2010: Gender Disparity

Based on the data from six Chinese National Surveys on Students Constitution and Health (CNSSCH) from 1985 to 2010, we explored the secular trend in the prevalence of obesity in urban Chinese children over a period of 25 years. The aim of this study was to examine the gender disparities in the prevalence of childhood obesity over time. The standardized prevalence of obesity in Chinese children increased rapidly during the past 25 years from 0.2% in 1985 to 8.1% in 2010. The increasing trend was significant in all age subgroups (p<0.01). Although the prevalence of obesity continuously increased in both boys and girls, the changing pace in boys was faster than that in girls. Age-specific prevalence odds ratios (PORs) of boys versus girls for obesity increased over time during the 25 year period. The prevalence of obesity in boys was significantly higher than in girls in all age-specific subgroups from 1991 and after. The gradually expanding gender disparity suggests the prevalence of obesity in boys contribute to a large and growing proportion of obese children. Therefore, it is critical for developing and implementing gender-specific preventive guidelines and public health policies in China.     

Thyroid autoimmunity in children and adolescents with type 1 diabetes mellitus. Effect of age, gender and HLA type

Type 1 diabetes is often associated with additional autoimmune phenomena. However, data reported on the frequency of thyroid autoimmunity differ vastly. Therefore, the prevalence of thyroid autoantibodies was evaluated at a large pediatric diabetes center in Southern Germany. 2,305 determinations (TPO and TG, ELISA) were performed in 495 patients with type 1 diabetes (234 boys, 261 girls; age at last measurement: 15.4 +/- 0.3 years, duration of diabetes 7. 5 +/- 0.2 years). The prevalence of elevated thyroid antibodies increased dramatically with age: from 3.7% in patients less than 5 years of age up to 25.3% in the age group 15-20 years (p < 0.0001). For children older than 10 years, girls were significantly more affected than boys (p < 0.0001). Thyroid autoimmunity tended to be more prevalent in the subgroup of patients with the HLA type DR3/DR4 compared to patients with other HLA types (p = 0.08). In children older than 10 years, basal TSH concentrations were significantly elevated in antibody-positive patients (p < 0.05). In conclusion, thyroid autoimmunity is prevalent in children and adolescents with type 1 diabetes. Adolescent girls and young women are especially affected. Yearly routine determinations of thyroid antibodies are therefore recommended.     

The relationship of lean limb volume to performance in the handgrip and standing long jump tests in boys and girls, aged 11.6–13.2 years

Twenty-three girls and 19 boys performed the handgrip and standing long jump (SLJ) tests. Their total forearm and leg volumes were calculated from circumference and length measurements and the lean volumes (bone + muscle) were calculated by making allowance for skinfold thickness. Although the boys were older than the girls (12.8 and 12.4 years), there was no significant difference in their heights or body masses. The absolute performances of the boys were superior to those of the girls in both tests (handgrip 234 and 205 N and SLJ 1.53 and 1.34 m), but when jumping performance was expressed as distance x body mass, there was no significant difference. In both tests, performance in terms of unit lean limb volume showed no significant gender difference. When performance was related to lean limb volume, both boys and girls showed a linear relationship in the two tests, with no significant difference between them. This absence of a gender difference contrasts with the results of a previous study on young adults and comparison shows that the relationships between lean limb volume and performance in the two tests for both boys and girls lie just below those of the young, adult females. The difference between the girls and the young adult females was just significant in the handgrip (p less than 0.05), but not significant in the SLJ (p greater than 0.25), whereas the differences between the boys and young adult males were significant (p less than 0.01) in both tests. Thus it would appear that a gender difference in the performance of skeletal muscle develops during adolescence and possible contributory factors are discussed.     

Socioeconomic status, sex, age, and ethnicity as determinants of body fat distribution for Guatemalan children

The distribution of subcutaneous fat at the triceps and subscapular skinfold sites is described for four groups of children living in Guatemala. These groups are high socioeconomic status (SES) children of Ladino (mixed Spanish and Indian) ancestry, high SES children of European ancestry, low SES Ladino children, and very low SES Indian children. The method of Healy and Tanner (1981) is used, employing regression and principal components analysis of log transformed skinfold values to divide "fatness" into two uncorrelated variables: size (amount of fat) and shape (fat pattern). Significant differences exist between groups in size, with lower SES groups having less fat than higher SES groups. No significant difference in fat pattern exists between the high SES Ladino and high SES European children. Significant differences do exist between the high SES groups and the low SES groups. The relative amount of subscapular fat increases from the high SES Ladinos and high SES Europeans, to the low SES Ladinos, to the very low SES Indians. In the high SES European and high SES Ladino samples, girls have significantly more arm fat than boys. There is no significant difference in fat patterning between boys and girls in the two low SES samples. Finally, the relative amount of subscapular fat tends to increase with age in all four samples. These results indicate that fatness and fat patterning are independent anatomical characteristics, SES influences fat patterning; low SES children of both Ladino and Indian ancestry show greater reductions in arm fat than in trunk fat compared to high SES children, sexual dimorphism in fat patterning is SES dependent.(ABSTRACT TRUNCATED AT 250 WORDS)     

Lower Serum Adiponectin Levels in African‐American Boys

Objective: To examine adiponectin, an adipocyte‐secreted hormone with anti‐inflammatory and insulin‐sensitizing effects, in relation to race or gender in younger subjects. Research Methods and Procedures: The relationship of adiponectin, quantitated by radioimmunoassay, to anthropometric and metabolic factors (fasting insulin, glucose, and leptin) and reproductive hormones was examined in 46 healthy African Americans (25 girls/21 boys) and 40 whites (20 girls/20 boys) ranging in age from 12 to 21 years. Results: There was no statistical difference in BMI or in BMI percentile among the four groups. Sums of skinfolds, but not skinfold percentile, were significantly lower in boys than girls (p = 0.001 and p = 0.896, respectively), whereas there was no difference between racial groups. Leptin was significantly greater in girls (p = 0.0002). There was no difference in fasting serum glucose, insulin, or homeostasis model assessment score among any of the groups. There was a significant negative univariate relationship between serum adiponectin and both BMI and BMI percentile for the entire group (p = 0.006 and p = 0.005). In a multivariate model, BMI percentile (p = 0.005) and the interaction between race and gender (p = 0.026) were significant predictors of serum adiponectin. In this model, African‐American boys had the lowest serum adiponectin level, 37% less than white boys, who had the highest adiponectin levels. Discussion: Serum adiponectin levels are reduced in young obese subjects (African Americans and whites) and are lower in African‐American boys than white boys. A lower adiponectin level in African‐American boys may predispose this group to a greater risk of diabetes and cardiovascular disease.     

Parental education and living environmental influence on physical development, nutritional habits as well as level of physical activity in Polish children and adolescents

The aim of this work was to evaluate the physical development and nutritional status, the nutrition habits as well as level of physical activity of boys and girls in relation to the socio-economic status of their families. The study was conducted on a group of 529 boys and 535 girls aged 7-16 years from Swietokrzyskie Province in Poland. Boys and girls from high SES families had the greatest body height, BMI, upper arm muscle area, as well as upper arm fat tissue area, while the lowest values of these features occurred among those studied coming from families of a low SES. The higher the family SES, the higher habitual frequency of consuming vegetables and fruit as well as fish. The diet of children coming from higher SES families was also linked with a higher total protein content as well as animal protein, all analysed minerals and some vitamins, but there were no significant differences of energetic value in daily food rations as well as fat content. The longer time spent on some sedentary activities was connected with a higher family SES. The girls coming from a high status families also declared a higher level of physical activity, whereas such relationship was not observed among boys. A more rational set of nutritional habits observed among children from a higher SES families can be the basic reason for their higher advancement in development. A shorter time devoted to sedentary activities is assumed to be the main cause of a smaller relative body mass and less obesity among girls and boys from low SES families.     

Sex-Based Differences in Asthma among Preschool and School-Aged Children in Korea

The purpose of this study was to explore risk factors related to asthma prevalence among preschool and school-aged children using a representative national dataset from the Korea National Health and Nutrition Examination Survey (KNHANES) conducted from 2009–2011. We evaluated the demographic information, health status, household environment, socioeconomic status, and parents’ health status of 3,542 children aged 4–12 years. A sex-stratified multivariate logistic regression was used to obtain adjusted prevalence odds ratios (ORs) and 95% confidence intervals after accounting for primary sample units, stratification, and sample weights. The sex-specific asthma prevalence in the 4- to 12-year-old children was 7.39% in boys and 6.27% in girls. Boys and girls with comorbid atopic dermatitis were more likely to have asthma than those without atopic dermatitis (boys: OR = 2.20, p = 0.0071; girls: OR = 2.33, p = 0.0031). Boys and girls with ≥1 asthmatic parent were more likely to have asthma than those without asthmatic parents (boys: OR = 3.90, p = 0.0006; girls: OR = 3.65, p = 0.0138). As girls got older, the prevalence of asthma decreased (OR = 0.90, p = 0.0408). Girls residing in rural areas were 60% less likely to have asthma than those residing in urban areas (p = 0.0309). Boys with ≥5 family members were more likely to have asthma than those with ≤3 family members (OR = 2.45, p = 0.0323). The factors related to asthma prevalence may differ depending on sex in preschool and school-aged children. By understanding the characteristics of sex-based differences in asthma, individualized asthma management plans may be established clinically.     

Differences in physical activity between non-overweight, overweight and obese children

The purpose of the study was to find out differences in moderate to vigorous physical activity among non-overweight, overweight and obese children, and between boys and girls. The sample included 364 children (179 boys and 185 girls), aged 6.4 years (+/- 0.3 SD). Physical activity was assessed by 7-day questionnaire. Age adapted BMI was used as overweight and obesity indicator. The children were divided into non-overweight, overweight and obese groups. It was found out, that there are significant differences in non-overweight, overweight and obese children (p < 0.05). Boys were significantly (p < 0.05) less moderate to vigorous physical active than girls, especially in indoor activities. There were also significant differences (p < 0.05) in moderate to vigorous physical activity among non-overweight and obese boys and among overweight and obese boys in weekends and total weekly activity. In girls there are significant differences (p < 0.05) in non-overweight, overweight and groups in weekends and total weekly activity. It is possible to conclude, that obese boys and overweight and obese girls, are prone to less physical activity.     

Temporal patterns of medications dispensed to children and adolescents in a national insured population

This study aimed to comprehensively describe prevalence and temporal dispensing patterns for medications prescribed to children and adolescents in the United States. Participants were 1.6 million children (49% female) under 18 years old enrolled in a nation-wide, employer-provided insurance plan. All medication claims from 1999–2006 were reviewed retrospectively. Drugs were assigned to 16 broad therapeutic categories. Effects of trend over time, seasonality, age and gender on overall and within category prevalence were examined. Results: Mean monthly prevalence for dispensed medications was 23.5% (range 19.4–27.5), with highest rates in winter and lowest in July. The age group with the highest prevalence was one-year-old children. On average each month, 17.1% of all children were dispensed a single drug and 6.4% were dispensed two or more. Over time, prevalence for two or more drugs did not change, but the proportion of children dispensed a single drug decreased (slope -.02%, p = .001). Overall, boys had higher monthly rates than girls (average difference 0.9%, p = .002). However, differences by gender were greatest during middle childhood, especially for respiratory and central nervous system agents. Contraceptives accounted for a large proportion of dispensed medication to older teenage girls. Rates for the drugs with the highest prevalence in this study were moderately correlated (average Pearson r.66) with those from a previously published national survey. Conclusion: On average, nearly one quarter of a population of insured children in the United States was dispensed medication each month. This rate decreased somewhat over time, primarily because proportionally fewer children were dispensed a single medication. The rate for two or more drugs dispensed simultaneously remained steady.     

Race and gender differences in the relationships between anthropometrics and abdominal fat in youth

Objective: We examined the influence of race and gender on abdominal adipose tissue (AT) distribution for a given anthropometric measure including waist circumference (WC), waist‐to‐hip ratio (WHR) and waist‐to‐height (W/Ht) in youth. Methods and Procedures: Subjects included healthy 62 black and 98 white youth. A single transverse image of the abdomen (L4–L5) was obtained using computed tomography. Results: For a given BMI, there was a significant (P < 0.05) main effect of race and sex on the relationship between BMI and WC, such that boys and whites had a higher WC than girls and blacks. There was a significant (P < 0.05) main effect and interaction effect of gender on the relationship between WC and visceral AT, such that boys had a higher visceral AT than girls, and the difference was magnified with increasing WC. For a given WC, black boys and girls had higher abdominal subcutaneous AT (SAT) than white peers, wherein the magnitude of the difference is increased with increasing WC. For a given W/Ht, black boys had significantly (P < 0.05) lower visceral AT than white boys, but with no difference in girls. Black boys and girls had higher SAT than white peers, wherein the magnitude of the difference is increased with increasing W/Ht. Discussion: Our findings demonstrate a significant race and gender differential in the abdominal AT distribution for a given BMI, WC, WHR, and W/Ht. Future studies should take these differences into consideration when developing race‐ and gender‐specific anthropometric cut‐offs for obesity and obesity‐related health risks in youth.     

The Association between Disturbed Eating Behavior and Socioeconomic Status: The Online Korean Adolescent Panel Survey (OnKAPS)

Background

A limited amount of research, primarily conducted in Western countries, has suggested that higher socioeconomic status (SES) is associated with higher risk of eating disorders (EDs). However, little is known about this association in Asian countries. We examined the association of SES with disturbed eating behavior (DEB) and related factors in Korean adolescents.

Subjects

A nationwide online panel survey was conducted in a sample of adolescents (n = 6,943, 49.9% girls). DEB was measured with the 26-item Eating Attitudes Test (EAT-26). Participants who scored ≥20 on the EAT-26 were considered to have DEB. Participants’ SES was determined based on self-reported household economic status.

Results

The prevalence of DEB was 12.7%: 10.5% among boys and 14.8% among girls. Both boys and girls with DEB were more likely to perceive themselves as obese, experience higher levels of stress, and have lower academic achievement. The risk for DEB was significantly higher in boys of higher SES than in those of middle SES (OR = 1.45, 95%CI = 1.05–1.99 for high SES; OR = 5.16, 95%CI: 3.50–7.61 for highest SES). Among girls, higher risk of DEB was associated with the highest and lowest SES (OR = 1.52, 95%CI: 1.13–2.06 for lowest SES; OR = 2.22, 95%CI: 1.34–3.68 for highest SES).

Conclusions

Despite the lower prevalence of obesity in Korea compared with Western countries, the prevalence of DEB in Korean adolescents was high, especially among girls. Moreover, the association between SES and DEB followed a U-shaped curve for girls and a J-shaped curve for boys.     

Age and gender differences in the physical activity patterns of urban schoolchildren in Korea and China

Physical activity in childhood is important as it may establish adult behavior. However, few studies on physical activity in children have been conducted, especially in Asian children.We performed anthropometric measurements of 159 school children in two grades (grade 5: 10-11 years old and grade 8: 13-14 years old) from urban areas of Korea (n=79) and China (n=80). The total daily energy expenditure (TEE) was estimated for 7 consecutive days using an accelerometer.The mean height, weight, and body mass index (BMI) for boys and girls in both countries exceeded the US national reference median (CDC, 2000). Physical activity levels (PALs) were significantly higher in the grade 5 group (10-11 years old) and in girls than in boys for both grades. No significant difference in PALs or daily step-counts (STPs) was observed between 'normal' and 'overweight' subgroups based on BMI, although negative correlations were found between weight, BMI, or %body fat vs. PAL or STP among Korean girls and Chinese boys (r=0.32-0.38, all p<0.05). Daily variation in physical activity was observed in Korean children. In the Koreans (boys and girls, both grades pooled), TEE and STP were significantly lower than the 7-day average on Sundays, whereas for the Chinese population, STP did not clearly differ between the weekends and the week averages.In summary, PALs were higher in the fifth grade boys and girls than in the eighth grade children; interestingly, girls tended to have higher PALs than boys. Daily variation in physical activity was observed in Korea; children were less active on Sundays.     

Serum zinc,copper, zinc-to-copper ratio,and other essential elements and minerals in children with attention deficit/hyperactivity disorder (ADHD)

BackgroundEssential trace elements and minerals play a significant role in neurodevelopment. Although certain studies demonstrated impaired essential trace element and mineral status in children with ADHD, the existing data are insufficient. The objective of the present study was to assess serum trace element and mineral levels in children with ADHD.MethodsSerum trace element and mineral levels in 68 children with ADHD and 68 neurotypical controls were assessed using ICP-MS at NexION 300D (PerkinElmer Inc., USA) equipped with ESI SC-2 DX4 autosampler (Elemental Scientific Inc., USA).ResultsSerum Cr, Mg, and Zn levels in children with ADHD were 21 % (p = 0.010), 4 % (p = 0.005), and 7 % (p = 0. 001) lower as compared to the healthy controls, respectively. In turn, serum Cu/Zn values were 11 % higher than those in the control group. Age and gender had a significant impact on serum element levels in ADHD. Particularly, preschool children were characterized by significantly increased Cu (+8 %; p = 0.034), and Cu/Zn (+19 %; p < 0.001) values, whereas serum Zn (-9 %; p = 0.004) level was decreased. In primary school-aged children only 6 % (p = 0.007) lower Mg levels were observed. Both boys and girls with ADHD were characterized by 8 % (p = 0.016) lower serum Zn levels and 10 % (p = 0.049) higher Cu/Zn values when compared to neurotypical girls. Boys with ADHD also had significantly higher Cu/Zn, exceeding the respective control values by 12 % (p = 0.021), predominantly due to a 7 % (p = 0.035) decrease in serum Zn. Serum Mg levels were also found to be significantly lower than those in neurotypical children by 5 % (p = 0.007). In adjusted regression models serum Cr (β=-0.234; p = 0.009) and Cu/Zn (β = 0.245; p = 0.029) values were significantly associated with ADHD, respectively. Two-way ANOVA revealed a significant impact of ADHD on Cr, Mg, Zn, and Cu/Zn, whereas age was associated with Cu, I, Mg, Mo, and Cu/Zn, whereas gender accounted only for variability in serum Mn levels. Principal component analysis (PCA) also revealed significant contributions of Mg, Zn, and Cu/Zn values to ADHD variability.ConclusionsHypothetically, the observed decrease of essential trace elements, namely Mg and Zn, and elevation of Cu/Zn may significantly contribute to the risk of ADHD or its severity and/or comorbidity.     

Epidemiological study of wheeze,doctor diagnosed asthma,and cough in preschool children in Leicestershire.

OBJECTIVE--To determine the cumulative prevalences of wheeze and doctor diagnosed asthma and the point prevalences of recurrent cough and wheeze in children aged 5 years and under. DESIGN--Questionnaire survey of population based random sample of children registered on regional authority''s child health index for immunisation; questionnaire completed by parents. SETTING--Leicestershire. SUBJECTS--1650 white children born in 1985-9 who were surveyed in 1990. MAIN OUTCOME MEASURES--Cumulative prevalences of wheeze and doctor diagnosed asthma and point prevalences of recurrent cough and wheeze by age and sex. RESULTS--There were 1422 replies (86.2%; 726 for boys, 696 for girls). Overall, 11.0% (95% confidence interval 9.4% to 12.6%) of children had formally been diagnosed as having asthma, the cumulative prevalence in boys (12.7%) being somewhat higher than in girls (9.2%) (age adjusted odds ratio 1.47, p = 0.03). As expected, the cumulative prevalence of asthma increased significantly with age (7.5% (13/173) in children under 1 year, 15.9% (61/383) in children of 4 years and over; p < 0.001). The cumulative prevalence of wheeze overall was 15.6% (13.7% to 17.5%), being higher in boys (17.6%) than in girls (13.5%) (odds ratio 1.38, p = 0.03). The overall prevalence of recurrent cough without colds was 21.8% (19.6% to 23.9%), with a non-significant excess in boys (23.1% v 20.4%). The overall prevalence of wheezing attacks during the previous 12 months was 13.0% (11.3% to 14.8%) with a non-significant excess in boys (14.5% v 11.5%). CONCLUSIONS--These findings are baseline results and emphasise the importance of studying the age group of interest rather than relying on the recall of parents of school age children.     

Impact of Objective and Subjective Social Status on Obesity in a Biracial Cohort of Adolescents

Objective: To characterize the associations between socioeconomic status (SES), two levels of subjective social status (SSS), and adolescent obesity. Research Methods and Procedures: Cross‐sectional study of 1491 black and white adolescents attending public school in a suburban school district in Greater Cincinnati, Ohio. BMI ≥95th percentile derived from measured height and weight defined overweight. Students rated SSS on separate 10‐point scales for society and school. A parent provided information on parent education and household income for SES. Results: Although there were no sex differences in SES, black students were more likely to come from families with less well‐educated parents and lower incomes (p < 0.001). Black girls had the lowest societal SSS (p = 0.003), lowest school SSS (p = 0.046), and highest BMI (p < 0.001). Prevalence of overweight was highest among black girls (26.0%) and boys (26.2%), intermediate for white boys (17.2%), and least for white girls (11.6%). Logistic regression modeling revealed that parent education, household income, and school SSS were each associated with overweight. In a fully adjusted model, school SSS retained its association to overweight (odds ratio, 1.16; 95% CI, 1.06, 1.26) independent of SES. The association of school SSS was strongest among white girls, intermediate for white and black boys, and absent for black girls. Discussion: Perceptions of social stratification are independently associated with overweight. There were important racial and sex differences in the social status‐overweight association. SSS in the more immediate, local reference group, the school, had the strongest association to overweight.     

A Significant Increase in the Incidence of Central Precocious Puberty among Korean Girls from 2004 to 2010

Background

Few studies have explored the trends in central precocious puberty (CPP) in Asian populations. This study assessed the prevalence and annual incidence of CPP among Korean children.

Methods

Using data from the Korean Health Insurance Review Agency from 2004 to 2010, we reviewed the records of 21,351 children, including those registered with a diagnosis of CPP for the first time and those diagnosed with CPP who were treated with gonadotropin-releasing hormone analogs.

Results

The prevalence of CPP was 55.9 per 100,000 girls and 1.7 per 100,000 boys, respectively. The overall incidence of CPP was 15.3 per 100,000 girls, and 0.6 per 100,000 boys. The annual incidence of CPP in girls significantly increased from 3.3 to 50.4 per 100,000 girls; whereas in boys, it gradually increased from 0.3 to 1.2 per 100,000 boys. The annual incidence of CPP in girls consistently increased at all ages year by year, with greater increases at older ages (≥6 years of age), and smaller increases in girls aged < 6 years. In contrast, the annual incidence remained relatively constant in boys aged < 8 years, while a small increase was observed only in boys aged 8 years. The increase of annual incidence showed significant differences depending on age and gender (P <0.0001).

Conclusions

The annual incidence of CPP has substantially increased among Korean girls over the past 7 years. Continued monitoring of CPP trends among Korean children will be informative.     

Estimating height from arm span measurement in Malawian children

Arm span and standing height were measured in 289 boys and 337 girls aged 6-15 years who were free from physical deformities which can affect stature or arm span. The arm span exceeded height in all age groups of boys and in older girls. At the age of 7, 11 and 12 years girls were significantly taller than the boys and had longer arm span while at the age of 15 years, the trend was opposite. The mean difference between the two anthropometric parameters for boys was 5.45 +/- 4.21 cm (t = 3.556, p < 0.001) and for girls was 4.94 +/- 4.96 cm (t = 3.542, p < 0.001). Correlation coefficient between height and arm span measurements for Malawian boys was 0.983 and for girls was 0.986. Height, arm span and height-arm span difference increased with age of children while height to arm span ratio decreased. The gender difference in height-arm span differences was only significant at the age of 15 years. Multiple regression and cross validation were performed. Height of Malawian children of both sexes can be estimated from equation: Height (cm) = 15.756 + (0.168 x age) + (0.839 x arm span) (SEE = 0.760, R2 = 0.988).     

Adiposity is not equal in a multi-race/ethnic adolescent population: NHANES 1999-2004

BMI is the preferred measure of adiposity in adolescents. Recent evidence suggests that in adults the relationship between BMI and adiposity can vary by age and race/ethnicity. We investigated the relationship between BMI and percent body fat (%BF) in a large multi-ethnic, nationally representative sample of US adolescents (National Health and Nutrition Examination Survey, NHANES, 1999-2004). BMI was calculated; %BF was derived from dual-energy X-ray absorptiometry data and compared to BMI among adolescents from three groups: non-Hispanic white (NHW), non-Hispanic black (NHB), and Mexican-American (MA). Fractional polynomials were used to model a new equation to estimate %BF from a given BMI. MA boys weighed significantly less than either NHW or NHB boys, while only NHB girls weighed significantly more than the other girls. Among the boys there were no differences in mean BMI, whereas %BF differed significantly between all three groups. For the girls, both BMI and %BF differed significantly the groups with MA girls having the highest %BF. The significant correlates for modeling %BF from BMI included gender, age, race/ethnicity, weight, [formula in text]: the final model explained 79% of the variance in %BF. NHB adolescents had significantly lower %BF for BMI and MA had higher than NHW. Our results indicate that BMI may not be an equivalent measure of %BF in a multi-ethnic population of US adolescents.     

Assessment of type A behavior in preschoolers

Teachers and mothers of 219 four-year-old preschoolers assessed their children for Type A behavior pattern using the Matthews Youth Test for Health (MYTH). The sample was derived from five day care centers with Black, White, and Hispanic teachers and students from middle and lower class families. This study indicates that Type A behavior can be identified in four-year-old preschoolers on the basis of ratings by their teachers. A statistically significant difference was found between the ratings of Type A/B characteristics by teachers and those by mothers; however, these were not related to the sex or ethnicity of the children. Repeated measurements of Type A ratings in a subsample of the children at age five showed no significant change among boys or girls. However, repeated measurements at age six on a second subsample showed that boys had lower mean scores, i.e. were more Type B at age six than at age four.     

Age, gender and circadian or circasemidian blood pressure and heart rate variation of children.

Systolic (S) and diastolic (D) blood pressure (BP) and heart rate (HR) of clinically healthy children (24 boys and 15 girls) 3 to 7 years of age were measured with a standard mercury sphygmomanometer at 3-hour intervals for 24 hours in April 1991. The children slept and/or rested from 2100 to 0700 and napped from 1230 to 1530; they had meals at 0730, 1200 and 1800. A statistically significant circadian and about 12-hour (circasemidian) component of variation is documented for SBP and DBP of boys and girls and for HR of boys. No gender difference was found for the circadian and circasemidian components. A positive correlation with age is found for the MESOR and circadian amplitude of SBP and DBP (p < 0.05); a negative correlation with age is found for the MESOR of HR (p < 0.001).