Serum Vitamin D Levels Mediate the Association Between Physical Activity and Blood Pressure in Adolescents.

Individuals with low levels of vitamin D are associated with cardiovascular risks, such as elevated blood pressure (BP), and are; therefore, more likely to develop hypertension. Patients with vitamin D deficiency may face an increased risk of cardiovascular events. In this study, a multicenter, cross-sectional, and school-based investigation was conducted as part of the ERICA project. The sample comprised 1152 adolescents aged 12-17 years from 4 Brazilian cities. Anthropometric variables, BP measurements, and hydroxyvitamin D concentrations were assessed. A 2-level linear regression was fitted to examine the relationship between each level of BP and independent variables. Our findings indicate that movement behaviors were not associated with BP levels, with the exception of sleep time, which demonstrated a positive association. However, after adjustment, this association was found to be nonsignificant. Our study's mediation analysis revealed that vitamin D mediates up to 12.9% of the association between physical activity and systolic BP. Vitamin D is inversely associated with BP in adolescents. In addition to mediating the physical activity and systolic BP association, engaging in physical activity, particularly outdoors, can provide a dual benefit for adolescents by increasing serum vitamin D levels and assisting in the control of BP levels.

Psychometric Properties of the Online International Physical Activity Questionnaire in College Students.

INTRODUCTION: Due to the restrictions imposed to control the COVID-19 pandemic, there has been an increase in studies based on online surveys. However, there are important concerns about the validity and generalizability of results from online surveys. Thus, we aimed to test the reliability and validity of the online version of the International Physical Activity Questionnaire short form (IPAQ-SF) among college students from low-income regions. METHODS: This was a methodological feasibility study with a random stratified sample from a college located in the state of Maranhão in the city of Imperatriz (Brazil). The sample consisted of 195 college students (at least 17 years of age) to evaluate the validity and 117 students to evaluate the reliability. All data were collected in a self-reported online format (via Google Forms) twice, with an interval of 2 weeks. We used Spearman's correlation analysis for the reliability study. Additionally, we applied exploratory and confirmatory factor analysis to evaluate the structural validity. RESULTS: The questionnaire showed acceptable (rho > 0.30) and significant (p < 0.05) reliability, except for the question about the duration of sitting time on a weekend day. When assessing the construct validity (exploratory analysis), we identified a single factor that explained 88.8% of the variance. The 1-factor model showed acceptable model fit (SRMR = 0.039; CFI = 0.96; TLI = 0.90) in confirmatory analysis. CONCLUSIONS: The online version of the IPAQ-SF has acceptable reliability among college students from low-income regions and maintains the structure of the construct regarding to physical activity.

Blood pressure measurement in pediatric population: comparison between automated oscillometric devices and mercury sphygmomanometers-a systematic review and meta-analysis.

With the progressive elimination of mercury column devices for blood pressure (BP) measurement in children and adolescents, valid alternatives are needed. Oscillometric devices provide a replacement without mercury, are fully automated, and have excellent reliability among evaluators. Here, the goal was to test the accuracy of automatic blood pressure monitor devices compared to the mercury sphygmomanometer for BP measurement in children and adolescents. Electronic databases are EMBASE, MEDLINE (PubMed), SCOPUS, and Web of Science. We selected 8974 potentially eligible articles and two authors independently. We separately reviewed 370 full papers. Potentially eligible articles were selected according to the following criteria: (a) articles published in Portuguese, English, and Spanish; (b) screening of titles; (c) screening of abstracts; and (d) retrieval and screening of the full article to determine whether it met the inclusion criteria. We included 45 articles for analysis, 28 of which were selected for meta-analysis. The systolic BP measured by automatic blood pressure monitors presents 1.17 mmHg on average (95% CI 0.85; 1.48); for diastolic BP, it produced -0.08 mmHg (95% CI -0.69; 0.54) compared with a mercury sphygmomanometer. There is high heterogeneity between studies (> 90%) in the meta-analysis, partly explained by the device model, study environment, and observer training. Only articles that reported BP measurement by both methods were included.Conclusion: Automatic blood pressure monitors have strong measurement validity when compared with the mercury column. Thus, these can be safely used in blood pressure measurements of children and adolescents in clinical and epidemiological studies. What is Known: •The "gold standard" for indirect BP measurement is the mercury sphygmomanometer. •The accuracy of the automatic device is critical to any blood pressure measurement method. What is New: •Oscillometric or automatic devices can be a suitable alternative to auscultation for initial screening, consistent with current pediatric guidelines. •The automatic devices compared to the mercury column have a good validity of measurements, which can be used in blood pressure measurements of children and adolescents in clinical and epidemiological settings, provided that international protocols are followed.

Psychometric properties of 4-item questionnaire for sleep habits and time in a South American paediatric population.

OBJECTIVES: To assess the psychometric properties of 4-item questionnaire about sleep habits and time in South American children (3-10 years) and adolescents (11-18 years). MATERIAL AND METHODS: We evaluated 459 participants from seven South American cities. Two items from week and weekend days wake up time and bedtime were asked twice, with a 2-week interval. We calculated time spent in bed (subtracting wake up time from bedtime). Participants also answered the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) sleep time questionnaire. RESULTS: The questionnaire showed acceptable temporal stability in children and adolescents on total days (rho≥0.30; p<0.05). For total days, the questionnaire presented acceptable convergent validity only in children (rho from 0.48 to 0.62; p≤0.01) compared with the HELENA questionnaire. CONCLUSION: The 4-item questionnaire is a reliable and valid tool for children; however, its validity is not consistent in adolescents for sleep habits and time.

Height-based equations as screening tools for elevated blood pressure in the SAYCARE study.

This study evaluated the accuracy of four height-based equations: blood pressure to height ratio (BPHR), modified BPHR (MBPHR), new modified BPHR (NMBPHR), and height-based equations (HBE) for screening elevated BP in children and adolescents in the SAYCARE study. We measured height and BP of 829 children and adolescents from seven South American cities. Receiving operating curves were used to assess formula performance to diagnose elevated BP in comparison to the 2017 clinical guideline. Sensitivity, specificity, and positive and negative predictive values (PPV, NPV) were calculated for the four screening formulas. The diagnostic agreement was evaluated with the kappa coefficient. The HBE equation showed the maximum sensitivity (100%) in children, both for boys and girls, and showed the best performance results, with a very high NPV (>99%) and high PPV (>60%) except for female children (53.8%). In adolescents, the highest sensitivity (100%) was achieved with the NMBPHR for both sexes. Kappa coefficients indicated that HBE had the highest agreement with the gold standard diagnostic method (between 0.70 and 0.75), except for female children (0.57). Simplified methods are friendlier than the percentile gold standard tables. The HBE equation showed better performance than the other formulas in this Latin American pediatric population.

Intra-observer reliability of the anthropometric measurements in South American children and adolescents: the SAYCARE Study / Confiabilidad intraobservador de mediciones antropométricas en niños y adolescentes sudamericanos: Estudio SAYCARE

Introduction: the South American Youth/Child Cardiovascular and Environmental (SAYCARE) feasibility study aims to develop valid and reliable indicators to investigate health-related behavior and nutritional status in children and adolescents. Anthropometric measurements are one of the evaluated indicators in the study. The accuracy of the anthropometric data is very important and relies in the quality of the measurements. Objective: to describe the intra-observer reliability of ten anthropometric measurements: weight, height, circumferences (neck, arm, waist, hip) and skinfolds (triceps, subscapular, biceps and suprailiac) of children and adolescents from six South American cities: Lima, Medellin, Montevideo, Santiago, San Pablo and Teresina. Methods: prior to the study, fieldworkers from the seven centers participated in central training to ensure the application of standardized procedures in the anthropometric measurements. Intra-observer precision, technical error of measurement (TEM) and coefficient of reliability (R) were estimated for each measurement. Results: reliability of weight and height was above 99% in almost all cities. TEM for skinfold thickness was below 1.4 mm in children and 2.13 mm in adolescents, while reliability was above 95% in most of the skinfold measurements. TEM for circumferences was below 1.8 cm in children and 0.64 cm in adolescents, while reliability was above 99% in almost all circumferences. Conclusions: reliability of the anthropometric measurements in this study was high. In comparison with similar European or American studies, the reliability of the measurements taken in our study was, in most cases, similar or even higher

Introducción: el estudio piloto South American Youth/Child cARdiovascular and Environmental (SAYCARE) tiene como objetivo desarrollar indicadores válidos y confiables para investigar el estado nutricional y las conductas vinculadas a la salud en niños y adolescentes. Uno de estos indicadores son las mediciones antropométricas. La precisión de los datos antropométricos es muy importante y se basa en la calidad con que se toman las mediciones. Objetivos: describir la confiabilidad intraobservador de diez mediciones antropométricas: peso, talla, circunferencias (cuello, brazo, cintura, cadera) y pliegues (trÍceps, subscapular, bÍceps y suprailIaco) de niños y adolescentes de seis ciudades de Sudamérica: Lima, Medellín, Montevideo, Santiago, San Pablo and Teresina. Métodos: previo al estudio, los trabajadores de campo de los seis centros participaron de un entrenamiento centralizado, para asegurar la aplicación de procedimientos estandarizados en la toma de las mediciones antropométricas. Para determinar la precisión intraobservador, se estimó el error técnico de medición (TEM) y el coeficiente de confiabilidad (R) para cada medición. Resultados: la confiabilidad de las medidas de peso y la talla estuvo por encima del 99% en casi todas las ciudades. El TEM para el grosor de los pliegues estuvo debajo de 1,4 mm en los niños y de 2,13 mm en los adolescentes, mientras que la confiabilidad fue superior al 95% en la mayoría de las mediciones de los pliegues. El TEM para las circunferencias estuvo por debajo de 1,8 cm en los niños y de 0,64 cm en los adolescentes, mientras que la confiabilidad fue superior al 99% en casi todas las circunferencias. Conclusiones: la confiabilidad de las mediciones antropométricas en este estudio fue alta. Comparada con estudios similares realizados en Europa y Estados Unidos, la confiabilidad de las medidas tomadas en nuestro estudio es, en la mayoría de los casos, similar o aún más elevada

Intra-observer reliability of the anthropometric measurements in South American children and adolescents: the SAYCARE Study.

INTRODUCTION: Introduction: the South American Youth/Child Cardiovascular and Environmental (SAYCARE) feasibility study aims to develop valid and reliable indicators to investigate health-related behavior and nutritional status in children and adolescents. Anthropometric measurements are one of the evaluated indicators in the study. The accuracy of the anthropometric data is very important and relies in the quality of the measurements. Objective: to describe the intra-observer reliability of ten anthropometric measurements: weight, height, circumferences (neck, arm, waist, hip) and skinfolds (triceps, subscapular, biceps and suprailiac) of children and adolescents from six South American cities: Lima, Medellin, Montevideo, Santiago, San Pablo and Teresina. Methods: prior to the study, fieldworkers from the seven centers participated in central training to ensure the application of standardized procedures in the anthropometric measurements. Intra-observer precision, technical error of measurement (TEM) and coefficient of reliability (R) were estimated for each measurement. Results: reliability of weight and height was above 99% in almost all cities. TEM for skinfold thickness was below 1.4 mm in children and 2.13 mm in adolescents, while reliability was above 95% in most of the skinfold measurements. TEM for circumferences was below 1.8 cm in children and 0.64 cm in adolescents, while reliability was above 99% in almost all circumferences. Conclusions: reliability of the anthropometric measurements in this study was high. In comparison with similar European or American studies, the reliability of the measurements taken in our study was, in most cases, similar or even higher.

INTRODUCCIÓN: Introducción: el estudio piloto South American Youth/Child cARdiovascular and Environmental (SAYCARE) tiene como objetivo desarrollar indicadores válidos y confiables para investigar el estado nutricional y las conductas vinculadas a la salud en niños y adolescentes. Uno de estos indicadores son las mediciones antropométricas. La precisión de los datos antropométricos es muy importante y se basa en la calidad con que se toman las mediciones. Objetivos: describir la confiabilidad intraobservador de diez mediciones antropométricas: peso, talla, circunferencias (cuello, brazo, cintura, cadera) y pliegues (trÍceps, subscapular, bÍceps y suprailIaco) de niños y adolescentes de seis ciudades de Sudamérica: Lima, Medellín, Montevideo, Santiago, San Pablo and Teresina. Métodos: previo al estudio, los trabajadores de campo de los seis centros participaron de un entrenamiento centralizado, para asegurar la aplicación de procedimientos estandarizados en la toma de las mediciones antropométricas. Para determinar la precisión intraobservador, se estimó el error técnico de medición (TEM) y el coeficiente de confiabilidad (R) para cada medición. Resultados: la confiabilidad de las medidas de peso y la talla estuvo por encima del 99% en casi todas las ciudades. El TEM para el grosor de los pliegues estuvo debajo de 1,4 mm en los niños y de 2,13 mm en los adolescentes, mientras que la confiabilidad fue superior al 95% en la mayoría de las mediciones de los pliegues. El TEM para las circunferencias estuvo por debajo de 1,8 cm en los niños y de 0,64 cm en los adolescentes, mientras que la confiabilidad fue superior al 99% en casi todas las circunferencias. Conclusiones: la confiabilidad de las mediciones antropométricas en este estudio fue alta. Comparada con estudios similares realizados en Europa y Estados Unidos, la confiabilidad de las medidas tomadas en nuestro estudio es, en la mayoría de los casos, similar o aún más elevada.

Is the Measurement of Blood Pressure by Automatic Monitor in the South American Pediatric Population Accurate? SAYCARE Study.

OBJECTIVE: This study aimed to test the validity of an automatic oscillometric device to measure the blood pressure (BP) in children (n = 191) and adolescents (n = 127) aged 3 to 18 years. METHODS: Systolic BP (SBP) and diastolic BP (DBP) levels were measured simultaneous by automatic device and mercury column with Y-connection. To verify the validity, Bland-Altman plots and limits of agreement of 95% (95% LOA), specificity and sensitivity of the device, and the grade of British Hypertension Society (BHS) criteria were used. RESULTS: The monitor measurements demonstrated lower measurement bias (mean difference [95% LOA]): 1.4 (-9.9 to 12.8) mmHg in children and 4.3 (-7.8 to 16.5) mmHg in adolescents for SBP. For DBP, it was 2.2 (-7.4 to 11.7) mmHg in children and 1.4 (-8.4 to 11.1) mmHg in adolescents. The sensitivity in children was 21.4 (95% CI = 16.3-26.6), and in adolescents, it was 20.0 (95% CI = 13.2-26.8); the specificity was 95.9 (95% CI = 93.4-98.4) in children and 100.0 (95% CI = 100.0-100.0) in adolescents. The monitor-tested ratings are Grade B for SBP in children and SBP and DBP in adolescents and Grade C for DBP in children. CONCLUSIONS: The automatic monitor presented high values of specificity and lower values of sensitivity to the diagnosis of HBP; however, it can be considered accurate (lower measurement bias) and valid for epidemiological and clinical practice in accordance with BHS criteria.