Body composition and blood pressures in school children 6–14 years of age

Age of onset of pubertal characteristics in boys aged 6–14 years of the Province of L’Aquila (Abruzzo, Italy)

BACKGROUND

Previous results on growth patterns of children from central-southern Italy (Abruzzo region) showed an increasing tendency to obesity and suggested that the secular trend was still in progress in this region. However, data on pubertal development was lacking.

OBJECTIVE

The objective of the study was to provide population data on pubertal development in a sample of 535 boys aged 6-14 years as a contribution to the ongoing debate on earlier onset of pubertal traits and on the slowing down of the secular trend.

METHODS

A cross-sectional survey was used. Data for genital and pubic hair development (GD and PHD) were analysed by probit analysis.

RESULTS

The boys start developing sexual characteristics at age 9: 13.3% had entered stage 2 of GD and 8.9% showed PHD. At 13 years of age, 5% and 7.4% were still in stage 1 of GD and PHD, respectively, whereas almost one-third had attained stage 5 for both sexual characteristics. The median age for attainment of stage 2 was 11.2 years for GD, 11.5 years for PHD and 11 years for one or both of them.

CONCLUSIONS

These results are in line with those for several European and industrialized countries and do not show a significantly earlier onset of sexual maturation.

Body fatness and clustering of cardiovascular disease risk factors in Portuguese children and adolescents

Modifiable cardiovascular risk factors that increase the risk for cardiovascular diseases (CVD) in adult populations have also been observed in pediatric populations. Childhood and adolescence obesity has been strongly implicated in the clustering of risk factors. The aims of the present study were 1) to examine whether clustering of CVD risk factors, either biological risk factors (high blood pressure (HBP), percentage of high fat mass (%HBF), and high total cholesterol (HTC)) and one behavioral/lifestyle risk factor (low physical activity index (LPAI)) exist, and 2) to analyze the relationship between body fatness and the clustering of other risk factors. The cluster of CVD risk factors was determined in 1,533 (8-15 years of age) children, 731 males (age 10.8 +/- 2.3 years; weight, 40.6 +/- 12.7 kg; height, 143.1 +/- 14.1 cm; BMI, 19.4 +/- 3.4 kg(-2)) and 802 females (age, 11.0 +/- 2.4; weight, 41.0 +/- 12.4; height, 142.8 +/- 13.2; BMI, 19.7 +/- 3.5). Sex- and age-specific "high risk" quartiles were formed for each of the biological risk factors and the lifestyle factor. Thus, for blood pressure (high blood pressure, HBP), cholesterol (high cholesterol, HTC), and obesity (high percent of body fat, HBF), the sex- and age-adjusted 4th quartile (4Q) was defined as the "high risk" quartile, while for physical activity the 1st quartile (1Q) was defined as the "high risk" quartile. The majority of children (62% of boys and 62% of girls) at risk of obesity are at risk of another risk factor. In our sample, estimated ORs indicated that, compared with 1Q, the "risk of obesity" children and adolescents were two times as likely (P < 0.001) to have two or three risk factors. Our results suggest that children 8-15 years old in the highest quartile of body fatness are an increased risk of having a cluster of other risk factors, namely HBP, HTC, and LPAI. These data provide further evidence that juvenile obesity warrants early intervention because the patterns of unhealthy behavior are formed in adolescence and young adulthood.

Physical activity and biological risk factors clustering in pediatric population

BACKGROUND

From a preventive point of view, it is especially important to investigate the life style risk factors connected to cardiovascular disease (CVD) biological risk factors clustering. The purposes of this study were (I) to determine in pediatric population the coexistence of biological cardiovascular disease risk factors (high blood pressure (HBP), percentage of high fat mass (%HFM), and high total cholesterol (HTC)) and (II) to study the relationship between low physical activity, a lifestyle risk factor, with those biological risk factors.

METHODS

This study comprised 1461 children (699 males and 762 females) aged between 8 and 15 years old. The following measurements were carried out: blood pressure, percentage of fat mass, total cholesterol (TC), and physical activity. The quartiles, adjusted for age and gender, were the criterion used to classify the subjects at risk. Odds ratios and confidence intervals at 95% were used to study HBP, HTC, and %HFM clustering in both genders. Multinomial logistic regression was used to investigate the relationship between clustering and physical activity index (PAI).

RESULTS

The findings of this study indicated that there is clustering for the biological risk factors, specially between HBP and %HFM for females. It can be observed that about half of the subjects had at least one biological risk factor.

CONCLUSIONS

The results of the present study suggest that children and adolescents with higher PAI have a lower number of biological risk factors for CVD.

Age at menarche and age of onset of pubertal characteristics in 6-14-year-old girls from the Province of L'Aquila (Abruzzo, Italy)

The present study is part of a research project on growth models of children in an area of central-southern Italy. It analyzes the phases of pubertal breast development (BD) in 397 girls, pubic hair development (PHD) in 399 girls, and menarche in 583 girls from 6-14 years old. The status quo method was used to evaluate the age at menarche. Probit analysis was used to analyze the data for all three variables. The onset of BD and PHD (Tanner stage 2) occurs at age 7 in 6.1% of girls. Passage to stage 3 of one or both secondary sexual characteristics occurs at age 10 in 8.5% of girls. Comparison with data from the United States shows higher percentages of American white girls in stage 2 (or greater) of both characteristics at any age. The mean (median) age of onset (Tanner stage 2) of BD or PHD or both of them is 9.96 years. The passage to stage 3 occurs at age 12.36 for BD (95% confidence interval: 1.36 years) and at age 12.10 for PHD (95% confidence interval: 0.51 years). The mean age at menarche is 12.55 years, in general agreement with other values found in Italy. Sexual maturation at any considered stage for both pubertal characteristics is generally in line with literature data concerning other Mediterranean and industrialized countries or countries in which the demographic transition is in an advanced phase. It does not show a significant earlier onset. The evidence emerging from the general project suggests that the secular trend is still in progress in this region of Italy.