Pressão arterial em crianças e adolescentes : tendências longitudinais e sua associação com fatores de risco cardiometabólico.

Abstract

Introduction: Several risk factors are associated with pediatric hypertension, among the most cited are overweight and obesity. Like cardiovascular diseases, obesity can begin early in life and is widely recognized as a risk factor for the development of cardiometabolic comorbidities in adulthood. The expansion of adipose tissue in obesity is accompanied by the accumulation of immune cells that contribute to a state of chronic low-grade inflammation and dysregulated metabolism. The causes of cardiometabolic problems are not yet well understood, therefore, the importance of longitudinal investigation of risk factors that may influence these problems is noted. Paper I is a literature review in which the objective was to verify the factors associated with the development of systemic arterial hypertension in children and adolescents. The review was carried out in the Medline/Pubmed and Scielo databases, including studies published from 2013 to March 2022. The descriptors used were in accordance with MeSH (Medical SubjectHeadings) ― Hypertension AND Child AND Adolescent. From the results, it can be observed that factors related to the development of hypertension were varied, but it was possible to verify that obesity and also, waist circumference, fat percentage, waist-to-height ratio, lipid profile and history familial hypertension were the most related factors. Paper II is a longitudinal trend study with a total sample of 10,883 subjects, which aimed to analyze the trend in blood pressure collected in children and adolescents between 2004 and 2017 in a municipality in southern Brazil. Children and adolescents were randomly selected and their blood pressure data were collected in the years 2004/05, 2008/09, 2011/2012, 2014/2015 and 2016/2017. An upward trend was found in mean diastolic blood pressure (DBP) values from 2004 to 2017, for the total sample and for boys and girls separately (all p<0.001). Specifically, each year after the first assessment was associated with an increase of 0.265 mmHg in DBP for the entire sample. In boys there was a tendency for DBP to increase by 0.249 mmHg each year, while in girls there was a tendency for DBP to increase by 0.278 mmHg each year. No associations were observed for systolic blood pressure (SBP). Furthermore, there was an increasing trend in the relative frequencies of altered PAD only from 2004 to 2017. The odds ratio for the occurrence of altered DBP each year was 1.05 (95% CI: 1.03; 1.07), 1.03 (95% CI: 1.01; 1.05), 1.04 (95% CI: 1.03; 1.05) for boys, girls and total sample, respectively. Additionally, while in 2004 13.2% of the sample was classified as having altered DBP, in 2016-17 this percentage increased to 21.6%. Paper III is a cross-sectional study that included 1,038 schoolchildren, aged between 13 and 18 years, from a municipality in the southern region of Brazil that aimed to verify the multiplicative interaction between waist circumference (WC) and cardiorespiratory fitness (CRF) in the association with SBP and DBP in a sample of adolescents. The results show that there was a significant interaction between CRF and WC Z-scores in women in the SBP (B = 0.117, p = 0.004) and DBP (B = 0.127, p = 0.004) prediction models, indicating that both the association between CRF and SBP and the association between CRF and DBP in females are moderated by WC. However, it was demonstrated that higher blood pressure levels were observed among adolescents in the 84th WC percentile, regardless of CRF. Finally, Paper IV aimed to investigate the longitudinal relationship between the Systemic Immuno-Inflammation Index (SIII), adiposity, glycemic and lipid profile, and blood pressure after two years, in children and adolescents through Structural Equation Modeling. The models included two factors (latent variables) composed of the following variables: 1) Adiposity: BMI and WC; 2) A glycemic/lipid index (GLY+LIP): total cholesterol, glucose and triglycerides; and two variables observed: A systemic immuno-inflammation index (SIII), calculated from the count of neutrophils, lymphocytes and platelets) and blood pressure (SBP and DBP). All variables were collected at baseline (2014/2015) except blood pressure, which was the variable collected at follow-up (2016/2017). The first model tested the association between SIII, adiposity, GLY+LIP and SBP, and the second model used the same variables, but related to DBP. In the model that included SBP, the results demonstrate a statistically significant association between the Adiposity factor and the GLY+LIP factor (B=0.133, CI=0.032; 0.234), between the Adiposity factor and SIII (B=0.209, CI=0.065; 0.354), and between the adiposity factor and SBP at follow-up (B=0.483; CI=0.347; 0.620). In the second model, this one using DBP as an outcome, between the Adiposity factor and the GLY+LIP factor (B=0.134, CI=0.032; 0.235), between the Adiposity factor and SIII (B=0.24, CI=0.063; 0.345), and between the adiposity factor and the PAD outcome at follow-up (B=0.469, CI=0.342; 0.596). Thus, we can conclude that only adiposity was directly associated with SBP and DBP, demonstrating an influence on higher blood pressure levels. Furthermore, adiposity was also associated with higher values of SIII and the GLY+LIP.