Anthropometric risk factors for elevated blood pressure in adolescents in Turkey aged 11-17

Associations between Neck Circumference, Mid-Upper Arm Circumference, Wrist Circumference, and High Blood Pressure among Lithuanian Children and Adolescents: A Cross-Sectional Study

(1) Background: High blood pressure (HBP) and obesity are significant and growing public health issues worldwide. Our study aimed to evaluate the associations of neck circumference (NC), mid-upper arm circumference (MUAC), and wrist circumference (WrC) with HBP among Lithuanian children and adolescents aged 7-17 years. (2) Methods: In this cross-sectional study, data on BP and anthropometric measurements were analysed in 3688 children and adolescents aged 7-17 years. Multivariate logistic regression analysis was used to estimate the associations between anthropometric indices and HBP. (3) Results: Overall, the prevalence rates of elevated BP and hypertension were 13.7% and 12.9%, respectively. After adjustment for age, BMI, and WC, statistically significant elevated aORs were observed for associations between greater NC, MUAC, WrC, and HBP in boys (aORs: 2.13, 2.46, and 2.48, respectively) and in girls (aORs: 2.01, 2.36, and 2.09, respectively). Moreover, per-unit increase in NC, MUAC, and WrC was also associated with greater odds of HBP in boys (aORs: 1.20, 1.21, and 1.37, respectively) and in girls (aORs: 1.10, 1.10, and 1.21, respectively). The analysed anthropometric indices presented higher area under the curve values for predicting HBP in boys than in girls. (4) Conclusions: This study suggests that higher NC, MUAC, and WrC are associated with increased odds of HBP in Lithuanian children and adolescents.

Physical fitness mediates and predicts for high blood pressure among children in relation to weight status

Background

Pediatric hypertension contributes to adulthood hypertension and target organ damage. Obesity is a well-known predictor for pediatric hypertension; however, the relationship between physical fitness and blood pressure (BP) is unclear among children. This study aimed to compare the differences in demographics, anthropometrics, and physical fitness across BP subgroups and investigate whether physical fitness was related to pediatric hypertension independent of weight status.

Methods

This quantitative, cross-sectional study investigated demographic, anthropometric, physical fitness, and BP measures among 360 healthy school-aged children. Continuous variables were compared across BP subgroups with the one-way analysis of variance. Mediation and moderation analyses were used to explore the mechanism. Multivariable regression models were used to assess independent associations for hypertension.

Results

There were 177 (49.2%), 37 (10.3%), and 146 (40.6%) children in the normotensive, elevated BP, and hypertensive subgroups, respectively. The hypertensive subgroup had higher body mass index (BMI) and waist/height ratio percentiles and performed worse in 800-m run, standing long jump (SLJ), and 1-min sit-ups than the normotensive subgroup. Furthermore, the 800-m run percentile (total effect: β = 0.308, standard error = 0.044, p < 0.001) and sit and reach percentile (total effect: β = 0.308, standard error = 0.044, p < 0.001) mediated the relationship between the BMI percentile and systolic BP percentile; the SLJ percentile was directly associated with the diastolic BP percentile (β,-0.197, 95% confidence interval,-0.298-0.097; p < 0.001). The parsimonious model of multivariable regression models revealed that the SLJ percentile (adjusted exp (β), 0.992, 95% confidence interval, 0.985-0.999; p = 0.042) and BMI percentile (adjusted exp (β), 1.024, 95% confidence interval, 1.016-1.032; p < 0.001) were two independent predictors for pediatric hypertension.

Conclusion

Physical fitness mediates the relationship between anthropometric and BP measures. The SLJ percentile is associated with pediatric hypertension independent of the BMI percentile. Proactive screening and health promotion for not only healthy weight status but also good physical fitness may be beneficial for BP control among school-aged students.

Accuracy of anthropometric indicators of obesity to identify high blood pressure in adolescents-systematic review

Background

Anthropometric indicators of obesity have been associated with blood pressure in adolescents. However, the accuracy of anthropometric indicators of obesity for screening for high blood pressure (HBP) in adolescents is not known. Thus, the aim of the present study was to summarize the set of evidence regarding the predictive ability of anthropometric indicators of obesity to identify HBP in adolescents.

Methods

Searches were performed in five databases: MEDLINE, Web of Knowledge, Scopus, Scientific Electronic online (SciELO) and SportDiscus. The inclusion criteria for studies were: adolescents aged 10-19 years or mean age included in this range, observational and intervention studies, studies that proposed cutoff points for anthropometric indicators of obesity, and studies in English, Portuguese and Spanish. The methodological quality of studies was assessed using the QUADAS-2 instrument.

Results

Ten studies met the inclusion criteria and had their information summarized. Based on the information described in these studies, the anthropometric indicators body mass index (BMI), waist circumference (WC), waist-to-height-ratio (WHtR), triceps skinfold thickness, body adiposity index, C index, body mass, waist-to-arm span ratio, arm fat area, average arm perimeter, fat percentage and arm span were likely to be used in high blood pressure (HBP) screening among adolescents. However, only one study showed acceptable values (moderate to high precision) in relation to the accuracy measurements of described cutoffs.

Conclusion

Caution is suggested in the use of anthropometric indicators of obesity for HBP screening in adolescents, in which a greater number of studies with accurate diagnostic tools are necessary.

Proposition of Cutoff Points for Anthropometric Indicators to Identify High Blood Pressure in Adolescents

Aim

To propose cutoff points for anthropometric indicators for high blood pressure (HBP) screening in adolescents and to identify, among these indicators, those more accurately for boys and girls.

Methods

This cross-sectional study was carried out in the city of São José, SC, Brazil with 634 adolescents aged 14 to 19 years. Blood pressure levels were measured using a digital oscillometric sphygmomanometer and adolescents were classified as having HBP or not. Anthropometric indicators were calculated based on anthropometric measurements such as body mass (BM), height, waist circumference (WC), hip circumference (HC) and triceps, subscapularis, suprailiac, and midcalf skinfold thickness (SF). The Receiver Operating Characteristic Curve (ROC) was used to analyze the predictive capacity of anthropometric indicators in the identification of HBP.

Results

Higher values of Area Under the Curve (AUC) were for the anthropometric indicators BM (0.67; 95%CI: 0.62-0.72), body mass index (BMI) (0.67; 95%CI: 0.62-0.72), and WC (0.67; 95%CI: 0.62-0.71) for males. For females, no anthropometric indicator had discriminatory power for HBP screening. The cutoff points for the anthropometric indicators with discriminatory power for HBP screening in males were BM > 64.80 Kg, BMI > 21.76 Kg/m2, fat percentage (FP) > 15.75, waist height to ratio (WHtR) > 0.41, WC > 73.00 cm, and HC > 92.25 cm.

Conclusion

Anthropometric indicators of body adiposity had greater discriminatory power of HBP screening in males. For females, caution is suggested because the anthropometric indicators showed AUC values (95%CI) below 0.60.

The Relationship between Under-Nutrition and Hypertension among Ellisras Children and Adolescents Aged 9 to 17 Years

Background: Globally, under-nutrition and hypertension in children has been associated with the risk of developing cardiovascular disease (CVD) in adulthood. The main objective of this study was to investigate the relationship between under-nutrition and hypertension, furthermore, to determine the risk of developing hypertension due to under-nutrition. Methods: The study comprised of 1701 participants (874 boys and 827 girls) between the ages of 9 and 17 years old. All anthropometric and blood pressure measurements were taken according to standard procedures. Mid-upper arm circumference (MUAC), body mass index (BMI), upper arm fat area (UFA), total upper arm area (TUAA) and upper arm muscle area (UMA) of Ellisras children were compared with the National Health and Nutrition Examination Survey III reference population. The linear regression models were used to determine the relationship between under-nutrition with hypertension for unadjusted and then adjusted for age and gender. The logistic regression model was used to determine the risk of under-nutrition on developing hypertension for unadjusted and adjusted for age and gender. Results: There was a positive significant (p < 0.0001) association between all under-nutrition variables (MUAC, BMI, UFA, TUAA and UMA) and systolic blood pressure (SBP; beta ranges between 0.84 and 2.78), and diastolic blood pressure (DBP; beta ranges between 0.3 and 1.08 before adjusting and after adjusting for age and gender (SBP, beta ranges between 0.59 and 2.00 and DBP (beta ranges between 0.24 and 0.80. Conclusion: The prevalence of under-nutrition was high while the prevalence of hypertension was low in this study. The mean under-nutrition variables (BMI, UFA, UMA and MUAC) of Ellisras children were far lower compared to the NHANES III reference population. Hypertension was significantly associated with under-nutrition in this study.

Are Body Composition Parameters Better than Conventional Anthropometric Measures in Predicting Pediatric Hypertension?

Body composition (BC) parameters are associated with cardiometabolic diseases in children; however, the importance of BC parameters for predicting pediatric hypertension is inconclusive. This cross-sectional study aimed to compare the difference in predictive values of BC parameters and conventional anthropometric measures for pediatric hypertension in school-aged children. A total of 340 children (177 girls and 163 boys) with a mean age of 8.8 ± 1.7 years and mean body mass index (BMI) z-score of 0.50 ± 1.24 were enrolled (102 hypertensive children and 238 normotensive children). Significantly higher values of anthropometric measures (BMI, BMI z-score, BMI percentile, waist-to-height ratio) and BC parameters (body-fat percentage, muscle weight, fat mass, fat-free mass) were observed among the hypertensive subgroup compared to their normotensive counterparts. A prediction model combining fat mass ≥ 3.65 kg and fat-free mass ≥ 34.65 kg (area under the receiver operating characteristic curve = 0.688; sensitivity = 66.7%; specificity = 89.9%) performed better than BMI alone (area under the receiver operating characteristic curve = 0.649; sensitivity = 55.9%; specificity = 73.9%) in predicting hypertension. In conclusion, BC parameters are better than anthropometric measures in predicting pediatric hypertension. BC measuring is a reasonable approach for risk stratification in pediatric hypertension.

Cardiorespiratory fitness, adiposity, and ambulatory blood pressure in adolescents

BACKGROUND

This study examined the association of cardiorespiratory fitness (fitness) and adiposity (Body Mass Index [BMI] and waist circumference [WC]) with ambulatory blood pressure (ABP) and tested the moderating effect of adiposity on the association between fitness and ABP.

METHODS

A cross-sectional study was conducted with 370 adolescents aged 11-16 years. Fitness was assessed by a height-adjusted step test and estimated by heart rate recovery, defined as the difference between peak heart rate during exercise and heart rate two minutes postexercise. Adiposity was measured using dichotomized values for percentiles of BMI (≥85th) and WC (≥50th). ABP was measured every 30-60 minutes over 24 hours on a school day. Mixed-effects regression analysis was used.

RESULTS

Each unit increase in fitness was associated with a decrease of systolic blood pressure (SBP) [-0.058 mmHg, P=0.001] and diastolic blood pressure (DBP) [-0.043 mmHg, P<0.001] after adjustment for WC and covariates. Each unit increase in fitness was associated with a decrease in SBP [-0.058 mmHg, P=0.001] and DBP [-0.045 mmHg, P<0.001] after adjustment for BMI and covariates. Fitness and BMI≥85th percentile (or WC ≥ 50th percentile) interactions were not associated with ABP after adjustment for covariates.

CONCLUSIONS

Our findings indicate a small but statistically significant inverse effect of fitness on ABP in adolescents. No evidence of a modifying effect of adiposity on this association suggesting that fitness and weight management have essential roles for maintaining lower ABP in adolescents.

Análisis de la condición física según sexo, edad, índice de masa corporal y nivel de actividad física en estudiantes de primaria en España

Introducción. La evidencia científica sugiere que la calidad de vida de los escolares se relaciona de forma directa con el estado de su condición física (CF).Objetivo. Analizar la CF según edad, sexo, índice de masa corporal (IMC) y nivel de actividad física en estudiantes de primaria.Materiales y métodos. Se realizó un estudio descriptivo transversal con 103 escolares entre 8 y 12 años de España. La CF se midió mediante la batería ALPHA-Fitness y la actividad física, con el cuestionario Physician-based Assessment and Counseling for Exercise. Los participantes se categorizaron según su nivel de actividad física (no activos versus activos) y su IMC (normo-peso versus sobrepeso-obesidad). Para el análisis se aplicó estadística paramétrica.Resultados. Los varones tuvieron un mejor nivel de CF, pero en ambos sexos se observó un leve incremento de esta a medida que aumentaba la edad. Los escolares con normopeso o activos físicamente tuvieron una mejor capacidad aeróbica y una composición corporal más saludable.Conclusión. Mantener niveles óptimos de CF a lo largo de la vida requiere de la adopción de un estilo de vida saludable desde la infancia, por tanto, es necesario promover la práctica autónoma de actividad física en los escolares.

The validity of mid-upper arm circumference as an indicator of low BMI in population screening for undernutrition: a study among adult slum dwellers in eastern India

OBJECTIVE

To explore the possibility for a statistically appropriate value of mid-upper arm circumference (MUAC) to identify the state of severe undernutrition, based on very low BMI, among adult Indian slum dwellers.

DESIGN

Cross-sectional study on adults. Height and MUAC were recorded and BMI was computed. Chronic energy deficiency (CED) was determined using the WHO international guidelines as BMI<18·5 kg/m2 and normal as BMI≥18·5 kg/m2. Besides calculating mean, sd and 25th, 50th and 75th percentile values, multiple linear regression analysis was undertaken to assess the associations between age, MUAC and BMI. Receiver-operating characteristic curve analysis was performed to determine the best MUAC cut-off to identify CED status. The χ 2 test was used to assess significance of the difference in CED prevalence across MUAC categories.

SETTING

An urban slum in Midnapore town, West Bengal State, India.

SUBJECTS

Male (n 467) and female (n 488) Indian slum dwellers.

RESULTS

MUAC of 22·7 and 21·9 cm, respectively, in males and females were the best cut-off points to differentiate CED from non-CED.

CONCLUSIONS

Results supported the validity of the WHO-recommended MUAC cut-offs for adults. There is still a need to establish statistically appropriate MUAC cut-offs to predict undernutrition and morbidity.

The Relationship Between Blood Pressure and Sleep Duration in Turkish Children: A Cross-Sectional Study

OBJECTIVE

As in adults, hypertension is also an important risk factor for cardiovascular disease in children. We aimed to evaluate the effect of sleep duration on blood pressure in normal weight Turkish children aged between 11-17 years.

METHODS

This cross-sectional study was conducted in the primary and secondary schools of the two central and ten outlying districts of Kayseri, Turkey. Subjects were 2860 children and adolescents (1385 boys, 1475 girls). Systolic and diastolic blood pressures were measured according to the recommendations of the Fourth Report of the National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents. Sleep duration was classified as follows: ≤8 hours, 8.1-8.9 hours, 9.0-9.9 hours or ≥10 hours.

RESULTS

For short sleeper boys and girls (participants with a sleep duration ≤8 h) the prevalence of prehypertension and hypertension was 35.0% and 30.8%, respectively. In univariate binary logistic regression analyses (age-adjusted), each unit increment in sleep duration (hours) in boys and girls, decreased the prehypertension and hypertension risk by 0.89 [odds ratio (OR)] [confidance interval (CI); 0.82-0.98] and 0.88 (OR) (CI; 0.81-0.97), respectively (p<0.05). In multiple binary logistic regression analyses [age- and body mass index (BMI)-adjusted] the location of the school and sleep duration categories were shown to be the most important factors for prehypertension and hypertension in both genders, while household income was the most important factor, only in boys.

CONCLUSIONS

A sleep duration ≤8 h is an independent risk factor for prehypertension and hypertension in Turkish children aged 11-17 years.

Prevalence of hypertension determined by ambulatory blood pressure monitoring (ABPM) and body composition in long-term survivors of childhood cancer

AIM

In recent years, survival rates of childhood cancers have significantly increased, and occurrence of long-term adverse late effects (eg, insulin resistance, diabetes mellitus, metabolic syndrome, hypertension) has become increasingly important. Early diagnosis of obesity/hypertension in childhood is essential to avoid morbidity in the adulthood. Therefore, this study was aimed to determine the blood pressure (BP) profile by ambulatory BP monitoring (ABPM) method, and prevalence of hypertension, obesity, abdominal obesity among childhood cancer survivors.

MATERIAL AND METHOD

The study was carried out with 52 cancer survivors. The ABPM measurement was performed during 24 hours. The anthropometric measurements of patients were performed using standardized protocols. The body composition analysis was performed with bioelectrical impedance analysis (BIA) method. Statistical significance was considered at p < 0.05.

RESULTS

The mean age of patients was 12.84 ± 3.88 years. Time off therapy ranged 24-125 month. The prevalence of prehypertension and hypertension were 57.7% and 9.6%, respectively. There was no statistically significant relationship between diagnosis and BP status (p = 0.59). The prevalence of obesity, and abdominal obesity were 1.9% and 30.4%, respectively. There was a positive correlation between waist circumference (WC) and time off therapy (p = 0.046). The WC was found to be higher in patients who received cranial irradiation (p = 0.048). Weight/WC were higher in patients who used corticosteroids in the treatment (p = 0.019).

CONCLUSION

Careful follow up of BP, weight and WC is necessary for long-term cancer survivors to prevent complications. Especially patients who receive cranial radiotherapy and use corticosteroid are at increased risk of abdominal obesity.

Is high waist circumference and body weight associated with high blood pressure in Iranian primary school children?

INTRODUCTION AND OBJECTIVES

The prevalence of overweight, abdominal obesity and hypertension among children has increased worldwide including Iran over several decades. We carried out a study to provide current estimates of the prevalence and trends of hypertension, overweight and obesity along with the relationship between weight status and hypertension in Iranian school-children.

METHOD

This study was carried out among 1184 fifth-grade students, whose ages ranged from 11 to 14 years. Body weight, body mass index (BMI), height and waist circumference (WC), systolic (SBP) and diastolic blood pressure (DBP) were measured.

RESULTS

22.04 and 5.32 % of students were overweight and obese, respectively. The prevalence of overweight and obesity was significantly higher among girls than boys (all p = 0.02), whereas the prevalence of hypertension was significantly higher in boys than girls (p = 0.001). Although 27 % of boys and 24.32 % of girls had abdominal obesity, no significant associations were reported between abdominal obesity and sex (p = 0.12). The prevalence of hypertension in children with normal weight, overweight and obesity, was 3, 9.7 and 17.8 %, respectively (p < 0.01). We have obtained that the mean values of weight and WC were significantly higher in boys than girls. Based on linear regression, every 1 cm increase in abdominal circumference leads to an estimated DBP and SBP increase of 0.173 and 0.164 mmHg, respectively (p < 0.05).

CONCLUSIONS

This study showed a high prevalence of hypertension and obesity in a school-based population in Tehran, Iran, in which the prevalence of hypertension was significantly and positively correlated with weight and WC.

Waist-to-height ratio, body mass index and waist circumference for screening paediatric cardio-metabolic risk factors: a meta-analysis

Waist-to-height ratio (WHtR) is superior to body mass index and waist circumference for measuring adult cardio-metabolic risk factors. However, there is no meta-analysis to evaluate its discriminatory power in children and adolescents. A meta-analysis was conducted using multiple databases, including Embase and Medline. Studies were included that utilized receiver-operating characteristics curve analysis and published area under the receiver-operating characteristics curves (AUC) for adiposity indicators with hyperglycaemia, elevated blood pressure, dyslipidemia, metabolic syndrome and other cardio-metabolic outcomes. Thirty-four studies met the inclusion criteria. AUC values were extracted and pooled using a random-effects model and were weighted using the inverse variance method. The mean AUC values for each index were greater than 0.6 for most outcomes including hypertension. The values were the highest when screening for metabolic syndrome (AUC > 0.8). WHtR did not have significantly better screening power than other two indexes in most outcomes, except for elevated triglycerides when compared with body mass index and high metabolic risk score when compared with waist circumference. Although not being superior in discriminatory power, WHtR is convenient in terms of measurement and interpretation, which is advantageous in practice and allows for the quick identification of children with cardio-metabolic risk factors at an early age.

[Accuracy of body fat and waist circumference in predicting metabolic abnormalities indicating cardiovascular risk in adolescents]

OBJECTIVE

To evaluate the performance of percent body fat (%BF) and waist circumference (WC) in predicting metabolic abnormalities indicating cardiovascular risk in adolescents.

SUBJECTS AND METHODS

Cross-sectional study with a probabilistic sample of 573 adolescents aged 12 to 19 years from state public schools in Niterói, RJ. The Receiver Operating Characteristic Curve was used to evaluate the accuracy of WC and %BF in predicting alterations in blood pressure, lipid profile, and blood glucose.

RESULTS

The best %BF cutoff points were 21% for boys, and 23% for girls, with sensitivity (SE) and specificity (SP) of approximately 60%. The best WC cutoff points were 71 cm for boys, and 66 cm for girls (SE: 55% to 70%; SP: 55% to 78%).

CONCLUSION

Even the best cutoff points misidentified high proportions of adolescents with metabolic abnormalities. Caution is recommended in the use of these indicators for cardiovascular risk screening in this age group.

Associations between body mass index, waist circumference and body shape index with resting blood pressure in Portuguese adolescents

BACKGROUND

Elevated blood pressure (BP) in childhood and adolescence is associated with overweight and obesity. Recently a body shape index (ABSI) has been suggested as superior to body mass index (BMI, kg/m(2)) and waist circumference (WC) as a measure of disease risk.

OBJECTIVE

To examine the association between ABSI, BMI, WC and BP in Portuguese adolescents and to consider the role of ABSI, BMI and WC when examining this issue in adolescents.

METHODS AND PROCEDURES

Height, body mass, WC and resting blood pressure were assessed in 445 Portuguese adolescents (252 girls and 193 boys) aged 10-17 years.

RESULTS

ABSI, BMI and WC were all significantly related to both SBP and DBP (all p = 0.001 or better). ABSI, BMI and WC were all significant predictors of SBP and DBP for the whole sample and when analysed in separate gender groups (p = 0.001 or better in all cases). However, in all cases ABSI was a better predictor of BP than BMI or WC.

CONCLUSIONS

Although BMI and WC significantly predict resting BP in adolescents, the use of ABSI explained a greater amount of the variance in BP in this population. When examining the effect of weight status on BP, researchers should consider use of ABSI alongside BMI.

Current status of childhood obesity and its associated morbidities in Turkey

As a transitional society, rapid changes have occurred in the social, economic, nutritional and lifestyle aspects of the Turkish population over the last three decades. As a result, the prevalence of overweight and obesity has shown a dramatic increase in the adult Turkish population, reaching figures as high as 30-40%. Although there is no nationwide figure regarding the prevalence of overweight and obesity in Turkish children and adolescents, several local studies performed between 2000 and 2010 in different regions of the country have demonstrated varying prevalence rates of 10.3%-17.6% and 1.9%-7.8% for overweight and obesity, respectively, in children aged 6-16 years. The differences in the figures obtained in these regions are thought to be due to variations in the subject sampling. The figures appear to vary depending on residential (urban vs. rural) and economic conditions. Belonging to a high-income family, living in a large city, having obese parents, being of high birth weight, consuming sugar-sweetened beverages (soft drinks, juice drinks, etc.), and spending time in front of TV and PC were identified as the most common risk factors. Complications and co-morbidities of obesity have also started to appear in our pediatric population. Metabolic syndrome, diagnosed according to the International Diabetes Federation criteria, was found in 2.3% of Turkish schoolchildren aged 10-19 years. This rate was 28% in obese children. Preventive public measures have started to be implemented by the State and other bodies to control the rising trends in obesity.

Prehypertension in children and adolescents: association with body weight and neck circumference

OBJECTIVE

The present study was undertaken to investigate the role of neck circumference (NC) in predicting prehypertension in children and adolescents.

METHODS

We conducted a cross-sectional study including 6,802 children and adolescents (3,631 boys and 3,171 girls) aged 5-18 years. Main anthropometric data and related information were collected.

RESULTS

The prevalence of prehypertension was 14.4%, 16.4% and 17.1% in normal weight, overweight and obese group respectively. Among the participants with normal body mass index (BMI), higher NC was significantly associated with increased odds of prehypertension (OR: 1.439; 95% CI: 1.118 to 1.853) after adjustment for age, gender, BMI and WC. Significant associations between NC and either systolic blood pressure (SBP) (β=0.581 mmHg) or diastolic blood pressure (DBP) (β=0.236 mmHg) were found in the linear regression. No significant ORs were observed either in overweight or in obese categories.

CONCLUSION

We concluded that additional measure of NC might expand the ability of BMI for the identification of prehypertension in normal weight children and adolescents.

Intensified effect of adiposity on blood pressure in overweight and obese children

In children, blood pressure (BP) and risk for hypertension are proportional to degree of adiposity. Whether the relationship to BP is similar over the full range of adiposity is less clear. Subjects from a cohort study (n=1111; 50% male and 42% black) contributed 9102 semiannual BP and height/weight assessments. The mean enrollment age was 10.2 years, and mean follow-up was 4.5 years. Adiposity was expressed as body mass index percentile, which accounted for effects of age and sex. The following observations were made. The effect of relative adiposity on BP was minimal until the body mass index percentile reached 85, beginning of the overweight category, at which point the effect of adiposity on BP increased by 4-fold. Similarly intensified adiposity effects on BP were observed in children aged ≤10, 11 to 14 years, and ≥15 years. Serum levels of the adipose tissue-derived hormone, leptin, together with heart rate, showed an almost identically patterned relation to BP to that of body mass index percentile and BP, thus implicating a possible mediating role for leptin. In conclusion, there is a marked intensification of the influence of adiposity on BP when children reach the categories of overweight and obese. Among the possible pathways, leptin may be a potentially important mediator acting through the sympathetic nervous system (reflected in heart rate). The findings have relevance to interventions designed to prevent or treat adiposity-related increases in BP and to the analytic approaches used in epidemiological studies.