Body adiposity is associated with risk of high blood pressure in Portuguese schoolchildren

Association between blood pressure and angiotensin-converting enzymes activity in prepubertal children ∗

OBJECTIVES

Angiotensin-converting enzymes' (ACEs) relationship with blood pressure (BP) during childhood has not been clearly established. We aimed to compare ACE and ACE2 activities between BMI groups in a sample of prepubertal children, and to characterize the association between these enzymes' activities and BP.

METHODS

Cross-sectional study of 313 children aged 8-9 years old, included in the birth cohort Generation XXI (Portugal). Anthropometric measurements and 24-h ambulatory BP monitoring were performed. ACE and ACE2 activities were quantified by fluorometric methods.

RESULTS

Overweight/obese children demonstrated significantly higher ACE and ACE2 activities, when compared to their normal weight counterparts [median (P25-P75), ACE: 39.48 (30.52-48.97) vs. 42.90 (35.62-47.18) vs. 43.38 (33.49-49.89) mU/ml, P for trend = 0.009; ACE2: 10.41 (7.58-15.47) vs. 21.56 (13.34-29.09) vs. 29.00 (22.91-34.32) pM/min per ml, P for trend < 0.001, in normal weight, overweight and obese children, respectively]. In girls, night-time systolic BP (SBP) and diastolic BP (DBP) increased across tertiles of ACE activity ( P < 0.001 and P  = 0.002, respectively). ACE2 activity was associated with higher night-time SBP and DBP in overweight/obese girls ( P  = 0.037 and P  = 0.048, respectively) and night-time DBP in the BMI z-score girl adjusted model ( P  = 0.018). Median ACE2 levels were significantly higher among nondipper girls (16.7 vs. 11.6 pM/min per ml, P  = 0.009).

CONCLUSIONS

Our work shows that obesity is associated with activation of the renin-angiotensin-aldosterone system, with significant increase of ACE and ACE2 activities already in childhood. Also, we report sex differences in the association of ACE and ACE2 activities with BP.

Appraisal of Clinical Care Practices for Child Obesity Treatment. Part II: Comorbidities

The objective of this technical report is to provide clinicians with actionable evidence-based information upon which to make treatment decisions. In addition, this report will provide an evidence base on which to inform clinical practice guidelines for the management and treatment of overweight and obesity in children and adolescents. To this end, the goal of this report was to identify all relevant studies to answer 2 overarching key questions: (KQ1) "What are effective clinically based treatments for obesity?" and (KQ2) "What is the risk of comorbidities among children with obesity?" See Appendix 1 for the conceptual framework and a priori Key Questions.

Predictive Ability of the Estimate of Fat Mass to Detect Early-Onset Metabolic Syndrome in Prepubertal Children with Obesity

Body mass index (BMI), usually used as a body fatness marker, does not accurately discriminate between amounts of lean and fat mass, crucial factors in determining metabolic syndrome (MS) risk. We assessed the predictive ability of the estimate of FM (eFM) calculated using the following formula: FM = weight - exp(0.3073 × height2 - 10.0155 ×d-growth-standards/standards/body-mass-index-for-age-bmi-for-age weight- 1 + 0.004571 × weight - 0.9180 × ln(age) + 0.6488 × age0.5 + 0.04723×male + 2.8055) (exp = exponential function, score 1 if child was of black (BA), south Asian (SA), other Asian (AO), or other (other) ethnic origin and score 0 if not, ln = natural logarithmic transformation, male = 1, female = 0), to detect MS in 185 prepubertal obese children compared to other adiposity parameters. The eFM, BMI, waist circumference (WC), body shape index (ABSI), tri-ponderal mass index, and conicity index (C-Index) were calculated. Patients were classified as having MS if they met ≥ 3/5 of the following criteria: WC ≥ 95th percentile; triglycerides ≥ 95th percentile; HDL-cholesterol ≤ 5th percentile; blood pressure ≥ 95th percentile; fasting blood glucose ≥ 100 mg/dL; and/or HOMA-IR ≥ 97.5th percentile. MS occurred in 18.9% of obese subjects (p < 0.001), with a higher prevalence in females vs. males (p = 0.005). The eFM was correlated with BMI, WC, ABSI, and Con-I (p < 0.001). Higher eFM values were present in the MS vs. non-MS group (p < 0.001); the eFM was higher in patients with hypertension and insulin resistance (p < 0.01). The eFM shows a good predictive ability for MS. Additional to BMI, the identification of new parameters determinable with simple anthropometric measures and with a good ability for the early detection of MS, such as the eFM, may be useful in clinical practice, particularly when instrumentation to estimate the body composition is not available.

Association between Body Fat and Elevated Blood Pressure among Children and Adolescents Aged 7-17 Years: Using Dual-Energy X-ray Absorptiometry (DEXA) and Bioelectrical Impedance Analysis (BIA) from a Cross-Sectional Study in China

To investigate the associations between body fat percentage (BF%) with childhood blood pressure (BP) levels and elevated BP (EBP) risks, and further examine the validity of bioelectrical impedance analysis (BIA), we conducted a cross-sectional study of 1426 children and adolescents aged 7–17 years in Beijing, 2020. EBP, including elevated systolic BP (ESBP) and elevated diastolic BP (EDBP), was defined based on the age- and sex-specific 90th BP reference values of children and adolescents in China. BF% was measured by dual-energy X-ray absorptiometry (DEXA) and BIA devices, and was divided into four quartiles. Log-binomial models were applied to calculate odds ratios (ORs) and 95% confidence intervals (95%CI). Girls tended to have higher BF% levels than boys (p < 0.05). There was 41.0% of girls who developed EBP. High BF% was associated with increased BP levels with ORs of 0.364 (95%CI = 0.283–0.444) for SBP, 0.112 (95%CI = 0.059–0.165) for DBP, and 1.043 (95%CI = 1.027–1.059) for EBP, while the effects were more pronounced in girls and older-aged children. BIA devices agreed well with BF% assessment obtained by DEXA. High BF% might have negative effects on childhood BP. Convenient measurements of body fat might help to assess childhood obesity and potential risks of hypertension.

The association between fat mass and subclinical atherosclerosis in healthy schoolchildren

BACKGROUND AND AIMS

Childhood obesity is associated with increased risk of cardiovascular disease (CVD) later in life. The aims of this study were to investigate the change of atherosclerosis risk factors in three fat mass percentiles and to examine the association between fat mass and atherosclerosis risk factors among a group of schoolchildren.

METHODS

A total of 125 schoolchildren (64 boys) aged 10-15 years were distributed into three groups: (i) the lower fat mass (LFM) group, for participants who reported fat mass ≤50th percentile; (ii) the middle fat mass (MFM) group, for participants who reported fat mass >50th percentile and <75th percentile; and (iii) the higher fat mass (HFM) group for participants who reported ≥ 75th percentiles. Measurements of carotid intima-media thickness (cIMT) using high-resolution B-mode ultrasound, lipemic profile, blood pressure, serum proinflammatory cytokines and soluble adhesion molecules were performed.

RESULTS

Significant differences (p ≤ 0.05) were shown between the three groups in total cholesterol (TC), triglycerides (TG), LDL, interlukien-6 (IL-6), and interlukien-1 beta (IL-1β). Using multiple linear regression analysis of fat mass as the dependent variable with the studied subclinical atherosclerosis risk, fat mass was significantly (p ≤ 0.05) associated with the variation expressed in systolic blood pressure (β = 0.490), diastolic blood pressure (β = 0.470), TC (β = 0.399), TG (β = 0.306), HDL (β = -0.281), LDL (β = 0.446), E-selectin (β = 0.314), and cIMT (β = 0.257).

CONCLUSION

Higher fat mass is associated with increased risk of atherosclerosis in schoolchildren. Atherosclerosis risk factors including biomarkers of inflammation, endothelial dysfunction, a state of dyslipidemia, increased cIMT, and high blood pressure were associated with fat mass. Studies evaluating the appropriate fat mass cut-off points in children and adolescents are needed.

Participation in Non-professional Sports and Cardiovascular Outcomes Among Adolescents: ABCD Growth Study

OBJECTIVES

Sports are an important way to improve health during adolescence. However, it is still unclear whether the association between sports, blood pressure, and metabolic profile could be affected by sex, biological maturation, and trunk fatness. The aim of this study was to analyze the association between sports participation and the cluster of cardiovascular markers among adolescents of both sexes.

METHODS

A cross-sectional study involving 285 adolescents aged from 11 to 17 years of age (202 boys and 83 girls). Cardiovascular variables were composed of systolic blood pressure (SBP), diastolic blood pressure (DBP), resting heart rate (RHR), and carotid (CIMT) and femoral (FIMT) intima-media thickness, which were used to calculate the Cardiovascular_{Z score}. Sports participation was assessed through a face-to-face interview. Age of peak height velocity (APHV) was used as a covariate.

RESULTS

Among girls, the group engaged in sports presented lower values of RHR (sport: - 0.344 [95% CI - 0.650 to - 0.037] versus non-sport: 0.540 [95% CI 0.125 to 0.954]) and Cardiovascular_{Z score} (sport: - 0.585 [95% CI - 1.329 to 0.159] versus non-sport: 0.879 [95% CI - 0.127 to 1.884]), explaining 12.2% and 6.1% of all variance, respectively. Among boys, the group engaged in sports presented lower values of DBP (sport: - 0.158 [95% CI - 0.335 to 0.018] versus non-sport: 0.160 [95% CI - 0.091 to 0.412]) and FIMT (sport: - 0.128 [95% CI - 0.300 to - 0.044] versus non-sport: 0.211 [95% CI - 0.032 to 0.454]), explaining 2.2% and 2.6% of all variance, respectively.

CONCLUSIONS FOR PRACTICE

Adolescents engaged in sports presented healthier cardiovascular parameters, and sports participation seems to affect cardiovascular health differently in boys and girls.