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1.
Arq. bras. cardiol ; 119(4): 553-561, Oct. 2022. tab, graf
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1403372

ABSTRACT

Resumo Fundamento Tem-se sugerido que o consumo de bebidas energéticas (BEs) possa afetar a atividade cardiovascular. Objetivos Investigar os efeitos agudos da ingestão de BE sobre a variabilidade da frequência cardíaca (VFC) recuperação cardiovascular após exercício aeróbico moderado em homens de diferentes capacidades cardiorrespiratórias. Métodos Este é um estudo randomizado, duplo cego, crossover, controlado por placebo. Vinte e oito jovens adultos foram divididos em dois grupos de acordo com o pico de consumo de oxigênio (pico de VO2): (1) pico de VO2 alto (AO) - pico de VO2 > 52,15 mL/Kg/min, e (2) pico de VO2 baixo (BO) - pico de VO2 <52,15 mL/Kg/min. Os indivíduos de ambos os grupos foram submetidos a dois protocolos de exercícios em ordem aleatória: exercício moderado aeróbico (60% de pico de VO2) após a ingestão de 250 mL de água (protocolo placebo) ou 250 mL de BE (protocolo BE). Durante os testes de exercício, foram registrados valores de parâmetros cardiorrespiratórios e de VFC. Resultados Foram observadas diferenças significativas para o índice de LF (unidades normalizadas) entre "repouso" e "Rec1" nos grupos de AO e BO durante o protocolo BE. Para a razão LF/HF, foram observadas diferenças significativas entre "repouso" e Rec1 nos grupos AO e BO nos protocolos BE. Conclusão A ingestão aguda de BE retardou a recuperação da frequência cardíaca após o exercício em indivíduos com capacidade cardiorrespiratória baixa e indivíduos com capacidade cardiorrespiratória alta.


Abstract Background It has been suggested that the consumption of energy drinks (ED) may affect cardiovascular activity. Objectives to investigate the acute effects of ED intake on heart rate variability (HRV) and cardiovascular recovery after moderate aerobic exercise in males with different cardiorespiratory capacities. Methods This is a randomized, double-blind, crossover, placebo-controlled study. Twenty-eight young adults were split into two groups according to their peak oxygen consumption (VO2peak) values: (1) High VO2 peak (HO) - VO2 peak > 52.15 mL/kg/min, and (2) low VO2 peak (LO) - peak VO2 <52.15 mL/kg/min. Subjects of both groups underwent two exercise protocols in randomized order: moderate aerobic exercise (60% of VO2peak) following the intake of 250 mL of water (placebo protocol) or 250 mL of ED (ED protocol). During the exercise tests, values of cardiorespiratory and HRV parameters were recorded. Results Significant differences were observed for the LF (normalized units) index between rest and Rec1 in HO energy and LO groups during the ED protocol. For the LF/HF ratio, significant differences were seen between rest and Rec1 in HO and LO during ED protocols. Conclusion Acute ED intake delayed heart rate recovery after exercise in subjects with low and high cardiorespiratory fitness.

2.
J. Hum. Growth Dev. (Impr.) ; 30(2): 164-169, May-Aug. 2020. ilus, tab
Article in English | LILACS, INDEXPSI | ID: biblio-1114924

ABSTRACT

Social distancing was planned as a preventive measure to control the extensive spread of COVID-19. COVID-19-related deaths in Brazil were analyzed during the period of social distancing measures. Mortality data for COVID-19 was obtained from the Worldometer website (www.worldometer.info). Deaths were estimated up to the 31st day after the occurrence of the 5th COVID-19-related death in Brazil. Social distance was measured using Google's community mobility reports (https://www.google.com/covid19/mobility/). The Brazilian epidemic curves were interconnected, and mathematical models were evaluated to fit the mortality estimation curves. The optimistic model was defined in the opening period of social distancing and, therefore, in the lower mobility (40-60%). The realistic model was calculated according to relaxed social distance measures (<40%) and the pessimistic model was calculated based on the transmission rate between 2-3. Thus, the equations of the mathematical models provided the outcomes for the date of June 9, 2020, as follows: realistic model with 40,623 deaths, pessimistic model with 64,310 deaths and the optimistic model with a projection of 31,384 deaths. As a result of these analyzes, on May 24, 2020, there were a total of 22,965 deaths related to COVID-19, and those deaths included within the proposed mathematical models were 17,452 for the optimistic model, 22,623 for the realistic model and 32,825 for the pessimistic model. Thus, it is concluded that social distancing measures promoted by the Brazilian public managers contributes to the reduction in approximately ten thousand deaths related to COVID-19 in the current pandemic scenario.


INTRODUÇÃO: O distanciamento social foi planejado como uma medida preventiva para controlar a disseminação extensiva da COVID-19. Nós analisamos as mortes relacionadas à COVID-19 no Brasil durante o período de medidas de distanciamento social. Os dados de mortalidade do COVID-19 foram obtidos no site da Worldometer (www.worldometer.info). As mortes foram estimadas até o 31º dia após a 5ª morte. O distanciamento social foi medido por meio dos relatórios de mobilidade comunitária COVID-19; Google (https://www.google.com/covid19/mobility/). As curvas epidêmicas brasileiras foram interligadas e os modelos matemáticos foram avaliados para se ajustarem às curvas de estimativa de mortalidade. O modelo otimista foi fundado no período de abertura da distância social e, portanto, na menor mobilidade (40-60%). O modelo realista foi calculado de acordo com medidas de distanciamento social relaxado (<40%) e o modelo pessimista foi calculado com base em R0 entre 2-3. Sob essa situação, o modelo matemático realista estimou 40.623 mortes em 9 de junho de 2020, enquanto o modelo pessimista antecipou 64.310 mortes e o modelo otimista projetou 31.384. Até hoje (24 de maio de 2020), um total de 22.965 foram relatadas, enquanto nosso modelo projetou 17.452 para o modelo otimista, 22.623 para o modelo realista e 32.825 para o modelo pessimista. Observamos movimento reduzido ao longo deste período. Em resumo, o modelo matemático sugere que a mobilidade reduzida da comunidade diminuiu o total estimado de mortes relacionadas à COVID-19 no Brasil. Enfatizamos que mais procedimentos metodológicos serão necessários para confirmar esta teoria


Subject(s)
Humans , Male , Female , Social Isolation , Coronavirus Infections , Centers for Disease Control and Prevention, U.S. , Death , Severe acute respiratory syndrome-related coronavirus , Betacoronavirus
4.
Clinics ; 74: e809, 2019. tab, graf
Article in English | LILACS | ID: biblio-1019703

ABSTRACT

OBJECTIVES: We aimed to evaluate the effects of cataract surgery on cardiac autonomic modulation. METHODS: A cross-sectional and analytical study was conducted at the Hospital Maria Braido in the city of São Caetano do Sul, São Paulo, between 2015 and 2016. We investigated 19 patients of both sexes who were all over 50 years old; all patients had a diagnosis of senile or bilateral cataracts and were recommended to undergo implantation of the intraocular lens. Heart rate variability (HRV) was evaluated before, during and after cataract surgery. RESULTS: There were no significant changes in the time and geometric domains of HRV before, during or after surgery. The high-frequency (HF) band in normalized units (nu) on the spectral analysis significantly increased (p=0.02, Cohen's d=0.9, large effect size). However, the low-frequency (LF) band in nu significantly decreased during surgery (p=0.02, Cohen's d=0.9, large effect size). CONCLUSION: Throughout the intraocular lens implantation cataract surgery, there was an increase in parasympathetic modulation and a decrease in the sympathetic component of the heart rate (HR). We propose that this result is attributable to the supine position of the patients during surgery and the trigeminal reflex.


Subject(s)
Humans , Male , Female , Middle Aged , Aged , Autonomic Nervous System/physiopathology , Cataract Extraction/adverse effects , Lens Implantation, Intraocular/adverse effects , Heart Rate/physiology , Reference Values , Time Factors , Trigeminal Nerve/physiopathology , Body Mass Index , Cross-Sectional Studies , Prospective Studies , Statistics, Nonparametric
5.
Rev. bras. crescimento desenvolv. hum ; 28(3): 298-306, Jan.-Mar. 2018. graf, tab
Article in English | LILACS-Express | LILACS | ID: biblio-1013505

ABSTRACT

INTRODUCTION: Heart rate variability (HRV) can be assessed from RR-intervals. These are derived from an electrocardiographic PQRST-signature and can deviate in a chaotic or irregular manner. In the past, techniques from statistical physics have allowed researchers to study such systems OBJECTIVE: This study planned to assess the heart rate dynamics in young obese subjects by nonlinear metrics to heart rate variability METHOD: 86 subjects were split equally according to status. Heart rate was recorded with the subjects resting in a dorsal (prone) position for 30 minutes. The complexity of the RR-intervals was assessed by five Entropies, Detrended Fluctuation Analysis, Higuchi and Katz's fractal dimensions Following inconclusive tests of normality we calculated the One-Way Analysis of Variance, Kruskal-Wallis, and the Effect Sizes by Cohen's d significances RESULTS: It was established that Shannon, Renyi and Tsallis Entropies and the Higuchi and Katz's fractal dimensions could significantly discriminate the two groups. The three entropies were higher in obese youths, suggesting less predictable sets of RR intervals (p<0.0001; d≈1.0). Whilst the Higuchi (p<0.003; d≈0.76) and Katz's (p≈0.02; d≈0.57) fractal dimensions were lower in obese youths CONCLUSION: As with chaotic globals an increase in response was detected by three measures of entropy in young obese. This is counter to the decreasing response detected by fractal dimensions. Chaotic globals and entropies are more dependable than fractal dimensions when assessing the responses to obesity

6.
MedicalExpress (São Paulo, Online) ; 4(6)Nov.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-894369

ABSTRACT

OBJECTIVE: Rest arterial pressure has been shown to be associated with cardiovascular mortality. Autonomic heart rate control during recovery from exercise is estimated to detect changes in cardiovascular system, which may lead to cardiovascular diseases. We assessed the involvement of rest diastolic arterial pressure (DAP) on heart rate dynamics after exercise in normotensive physically active men. METHOD: We evaluated healthy physically active men aged 18 to 22 years old divided into two unequal groups: G1- rest DAP between 80 and 90 mmHg (N=11) and G2- rest DAP < 80mmHg (N=24). Volunteers performed physical exercise on a treadmill with intensity equivalent to 60% of Vmax. Heart rate recovery in the first (HRR1) and third (HRR3) minute after exercise were measured and heart rate variability (HRV) was examined in the time and frequency domain. Additionally, we performed the quantitative analysis of the Poincaré plot. HRV was recorded in the following phases: the 10-minute period before exercise, during exercise and the 60 minute period after exercise. RESULTS: We found no significant difference between G1 and G2 concerning HRV changes during exercise. The G2 group exhibited a delayed recovery of SDNN, RMSSD, RRTri, LF, HF, LF/HF, SD1 and SD2 indices during recovery from exercise. HRR1 and HRR3 was greater in the G2 group. CONCLUSION: Normotensive physically active men with DAP between 80 and 90 mmHg presented faster heart rate recovery and an accelerated recovery of heart rate autonomic control after aerobic exercise.


INTRODUÇÃO: A pressão arterial de repouso demonstrou estar associada à mortalidade cardiovascular. O controle autonômico da frequência cardíaca durante a recuperação pós-exercício é estimado para detetar mudanças no sistema cardiovascular, porque tais mudanças podem levar a doenças cardiovasculares. Avaliamos o envolvimento da pressão arterial diastólica de repouso (PAD) na dinâmica da frequência cardíaca após o exercício em homens normalmente ativos fisicamente normotensos. MÉTODO: Avaliamos homens saudáveis e fisicamente ativos com idades compreendidas entre os 18 e os 22 anos divididos em dois grupos desiguais: PAD de relaxamento G1 entre 80 e 90 mmHg (n=11) e PAD <80mmHg (n=24). Os voluntários realizaram exercícios físicos em uma esteira com intensidade equivalente a 60% da Vmax. A recuperação da frequência cardíaca no primeiro (HRR1) e terceiro (HRR3) minuto após o exercício foi medida e a variação da frequência cardíaca (VFC) foi examinada no domínio do tempo e da frequência. Além disso, realizamos a análise quantitativa da trama de Poincaré. A VFC foi registrada nas seguintes fases: os períodos de 10 minutos antes do exercício, durante o exercício e os períodos de 60 minutos após o exercício. RESULTADOS: Não encontramos diferença significativa entre G1 e G2 em relação às alterações da VFC durante o exercício. O G2 apresentou uma recuperação tardia dos índices SDNN, RMSSD, RRTri, LF, HF, LF/HF, SD1 e SD2 durante a recuperação do exercício. HRR1 e HRR3 foi maior no G2. CONCLUSÃO: Homens normais e fisicamente ativos com PAD entre 80 e 90 mmHg apresentaram RHE mais rápida e recuperação mais acelerada do controle autonômico da freqüência cardíaca após o exercício aeróbio.


Subject(s)
Autonomic Nervous System , Cardiovascular System , Cardiovascular Physiological Phenomena , Exercise Test , Arterial Pressure , Exercise , Heart Rate
7.
MedicalExpress (São Paulo, Online) ; 4(3)May-June 2017. tab, graf
Article in English | LILACS | ID: biblio-894351

ABSTRACT

OBJECTIVE: Nonlinear techniques to assess heart rate variability (HRV) have received much recent attention. We aimed to evaluate nonlinear HRV responses during recovery from exercise through the novel algorithm Higuchi Fractal Dimension. METHOD: We examined 35 healthy male volunteers aged between 18 and 35 years old. For the training of exercise intensity we used 60% of Vmax determined through a progressive test using the Conconi threshold. HRV was analyzed 10 minutes before and 10 minutes after exercise. We analyzed the geometric indices of HRV (SD1, a measure of short-term HRV and SD2, a measure of long-term HRV) and applied the Higuchi Fractal Dimension to RR intervals. RESULTS: During recovery from exercise the Poincaré plot indices SD1 and SD1/SD2 decreased while SD2 and SD2/SD1 increased (p<0.0001) compared to control at rest. All parameters of Higuchi Fractal Dimension analysis were lowered after exercise compared to control at rest (p<0.0001). CONCLUSION: Physical exercise acutely decreased the chaotic behavior of HRV as measured through the Higuchi Fractal Dimension analysis. Physiologically, this indicates that we detected complex changes in HRV immediately after exercise.


OBJETIVO: Métodos não-lineares para avaliar a variabilidade da freqüência cardíaca (VFC) têm recebido muita atenção recente. Nosso objetivo é analisar as respostas não-lineares da VFC durante a recuperação do exercício através do novo algoritmo da análise fractal da dimensão de Higuchi. MÉTODO: Foram examinados 35 voluntários saudáveis, com idade entre 18 e 35 anos. Para o treinamento de intensidade de exercício utilizamos 60% de Vmax determinado através de um teste progressivo utilizando o limiar de Conconi. A VFC foi analisada 10 minutos antes e 10 minutos após o exercício. Analisamos os índices geométricos de VFC (SD1, uma medida de VFC em curto prazo e SD2, uma medida de VFC em longo prazo) e aplicamos a Dimensão Fractal de Higuchi aos intervalos RR. RESULTADOS: Durante a recuperação do exercício, os índices de plot de Poincaré SD1 e SD1/SD2 diminuíram, enquanto que SD2 e SD2/SD1 aumentaram (p <0,0001) em relação ao repouso. Todos os parâmetros da análise da Dimensão Fractal de Higuchi foram reduzidos após o exercício em comparação com o controle em repouso (p <0,0001). CONCLUSÃO: O exercício físico diminuiu agudamente o comportamento complexo da VFC, conforme medido pela análise da Dimensão Fractal de Higuchi. Fisiologicamente, isso indica que detectamos alterações na complexidade da VFC imediatamente após o exercício.


Subject(s)
Humans , Male , Autonomic Nervous System , Algorithms , Cardiovascular System , Exercise/physiology , Nonlinear Dynamics , Heart Rate
8.
MedicalExpress (São Paulo, Online) ; 3(5)Sept.-Oct. 2016. graf
Article in English | LILACS | ID: biblio-829159

ABSTRACT

INTRODUCTION: Exercises with a flexible pole have been applied in clinical practice for upper limb rehabilitation. Nevertheless, its acute effects on cardiac autonomic regulation are unclear. OBJECTIVE: To evaluate the acute effects of exercise with flexible pole on complex behavior of heart rate variability (HRV). METHOD: We investigated 32 healthy female volunteers aged between 18 and 25 years who performed a session of exercise with a flexible pole. HRV was analyzed 10 minutes before and 10 minutes immediately after the exercise. RESULTS: Exercises with a flexible pole did not significantly change time and frequency domain indices of HRV. Non-linear analysis of HRV through the Higuchi Fractal Dimension was not significantly changed during recovery from exercise compared to the control reading at rest. CONCLUSION: Exercises with the flexible pole were unable to acutely change chaotic behavior of heart rate dynamics. This is advantageous for assessments of levels of rehabilitative treatment required in such patients; and their susceptibility to dynamical diseases.


INTRODUÇÃO: Exercícios com uma barra flexível têm sido usados na prática clínica para a reabilitação do membro superior. No entanto, os seus efeitos agudos sobre a regulação autonômica cardíaca não estão bem esclarecidas. OBJETIVO: Avaliar os efeitos agudos do exercício com barra flexível sobre o comportamento complexo da variabilidade da frequência cardíaca (VFC). MÉTODO: Foram investigadas 32 voluntárias saudáveis com idades entre 18 e 25 anos que realizaram uma sessão de exercício com barra flexível. A VFC foi analisada 10 minutos antes e 10 minutos imediatamente depois do exercício. RESULTADOS: Os exercícios com a barra flexível não alteraram significativamente os domínios de tempo e frequência de VFC. Análise não-linear da VFC através da Dimensão Fractal Higuchi mostra que a mesma não foi significativamente alterada durante a recuperação do exercício em relação ao controle pré-exercício. CONCLUSÃO: O exercício com a barra flexível não alterou profundamente o comportamento caótico da dinâmica da frequência cardíaca. Isto é vantajoso para a avaliação de níveis de tratamento de reabilitação necessário em tais pacientes; e sua suscetibilidade a doenças dinâmicas.


Subject(s)
Humans , Adult , Physical and Rehabilitation Medicine/methods , Autonomic Nervous System , Physical Exertion , Heart Rate
9.
MedicalExpress (São Paulo, Online) ; 3(2)Mar.-Apr. 2016. tab, graf
Article in English | LILACS | ID: lil-779132

ABSTRACT

OBJECTIVE: A previous study suggested that the p-value of normality test applied to RR intervals is an index able to quantify Heart Rate Variability (HRV) through correlation of traditional time and frequency domain indices. We investigate the association between the p-value of normality test applied in RR intervals and symbolic analysis of HRV. METHOD: We evaluated 32 healthy women between 18 and 30 years old. RR intervals were used for HRV analysis and we performed symbolic analysis, where RR intervals are joined by symbols. Sets of three consecutive symbols (RR intervals) were grouped into four types of clusters, as follows: 1. Three equal symbols (zero variation); 2: two equal, one divergent symbol (one variation); 3. Three different symbols monotonically ascending or descending (two like variations); 4. Three different symbols, forming a peak or a trough (two unlike variations). Frequency of occurrence of each type of cluster was calculated. Normality tests were applied to all RR intervals and the p-value was calculated. We computed the correlations between the p-value of normality test and symbolic analysis of HRV. RESULTS: Correlation coefficients between the p-value of normality test from Kolmorogov-Smirnov test and the four types of clusters showed no correlation for any of them. Likewise, the correlation coefficient index between the p-value of normality test calculated from the Shapiro-Wilk test and symbolic analysis produced no significant results for any of the four types of clusters. CONCLUSION: There was no significant correlation between the p-value of normality test and HRV symbolic analysis. The physiological significance of this result is that the PNT is not related to chaotic behavior of HRV.


OBJETIVO: Um estudo anterior sugeriu que o valor "p" do teste de normalidade (PNT) aplicado a intervalos RR é um índice capaz de quantificar variabilidade da frequência cardíaca através da correlação tradicional dos índices de tempo e frequência. Investigamos a associação entre o teste PNT aplicado a intervalos RR e a análise simbólica da variabilidade da frequência cardíaca. MÉTODO: Foram avaliadas 32 mulheres saudáveis entre 18 e 30 anos de idade. Os intervalos RR foram utilizados para análise da variabilidade da frequência cardíaca; foi realizada uma análise simbólica, onde intervalos RR são unidos por símbolos. Grupos de três símbolos consecutivos foram agrupados em quatro tipos de aglomerados, a saber: 1: três símbolos iguais (variação zero); 2: dois símbolos iguais, um divergente (uma variação); 3: três símbolos diferentes, monotonicamente crescentes ou decrescentes (duas variações iguais); 4: três símbolos diferentes, formando um pico ou uma calha (duas variações desiguais). Foi calculada a frequência de ocorrência de cada tipo de cluster. Testes de normalidade foram aplicados a todos os intervalos RR e o valor de "p" foi calculado. Calculamos as correlações entre o PNT e análise simbólica de HRV. RESULTADOS: Os coeficientes de correlação entre PNT de teste Kolmorogov-Smirnov e os quatro tipos de clusters não mostraram correlação com qualquer um deles. Da mesma forma, o coeficiente de correlação entre o índice PNT calculado a partir do teste de Shapiro-Wilk e a análise simbólica não produziu resultados significativos para qualquer dos quatro tipos de aglomerados. CONCLUSÃO: Não houve correlação significativa entre o PNT e análise simbólica da variabilidade da frequência cardíaca. O significado fisiológico deste resultado é que o PNT não está relacionado ao comportamento caótico da VFC.


Subject(s)
Humans , Female , Adult , Autonomic Nervous System/physiology , Cardiovascular System , Cardiovascular Physiological Phenomena , Normal Distribution , Heart Rate/physiology
10.
Braz. oral res. (Online) ; 30(1): e29, 2016. tab
Article in English | LILACS | ID: biblio-951991

ABSTRACT

Abstract Dental treatment promotes psychosomatic change that can influence the procedure and compromise the general well-being of the patient. In this context, it highlights the importance of evaluating the function of the autonomic nervous system in individuals undergoing endodontic treatment. Thus, this manuscript aimed to analyse cardiac autonomic modulation, through non-linear indices of heart rate variability (HRV) during endodontic treatment. Analysis of 50 subjects of either sex aged between 18 and 40 years diagnosed with irreversible pulp necrosis of lower molars undergoing endodontic treatment was undertaken. We carried out fractal and symbolic analysis of HRV, which was recorded in the first session of the endodontic treatment at four intervals: T1: 0-10 min before the onset of the treatment session; T2: 0-10 min after the application of anaesthesia; T3: throughout the period of treatment; and T4: 0-30 min after the end of the treatment session. There was reduction of α1 in T2 compared to T1 and T4 (p < 0.0001). The α2 index also reduced in T2 compared to T3 (p = 0.0035). There was an increase in the α1/α2 ratio in T4 compared to T2 and T3 (p = 0.0003). It was found that 0V% was significantly lower in T2 (p = 0.002), while 2UV% was significantly higher (p < 0.0001) when compared to other points in time. In conclusion, HRV is reduced during endodontic treatment, and after applying local anaesthetic the parasympathetic component of HRV increases. These data indicate that endodontic treatment acutely overcharges the heart, supporting the stress involved in this situation.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Young Adult , Root Canal Therapy/psychology , Heart Rate/physiology , Autonomic Nervous System/drug effects , Autonomic Nervous System/physiology , Stress, Psychological/physiopathology , Time Factors , Analysis of Variance , Dental Anxiety/physiopathology , Fractals , Statistics, Nonparametric , Heart Rate/drug effects , Anesthesia, Local
11.
Rev. bras. crescimento desenvolv. hum ; 26(2): 147-153, 2016. graf, tab
Article in English | LILACS | ID: lil-797805

ABSTRACT

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is categorized by a lowered attention span, recklessness, and hyperactivity. Autonomic nervous system inequality has previously been studied using the same data by chaotic global techniques. We aim to compare the autonomic function of children with ADHD and controls by analyzing heart rate variability (HRV) METHODS: 28 children with ADHD (22 boys, mean age 10.0 years ± 1.9 years) and 28 controls (15 boys, mean age 9.9 years ± 1.8 years) rested in supine position with spontaneous breathing for 20 minutes. Heart rate was recorded beat by beat. HRV analysis was performed by Higuchi Fractal Dimension technique. RESULTS: ADHD promoted an increase in the Higuchi Fractal Dimension. The optimum value of Kmax was 10. CONCLUSION: ADHD significantly altered cardiac autonomic modulation as measured by the Higuchi fractal dimension of HRV. It can therefore be stated that ADHD has increased the complexity of the HRV signal through cardiac autonomic modulation.


INTRODUÇÃO: O transtorno de deficit de atenção e hiperatividade (TDAH) é caracterizado por um período reduzido de atenção, impulsividade e hiperatividade. O desequilíbrio na função do sistema nervoso autônomo (SNA) tem sido previamente estudado utilizando-se técnicas globais da teoria do caos. OBJETIVO: comparar a função autonômica de crianças com TDAH e controles por meio da análise da variabilidade da frequência cardíaca (VFC) MÉTODO: 28 crianças com TDAH (22 meninos, com média de idade de 10,0 anos ± 1,9 anos) e 28 controles (15 meninos, com média de idade de 9,9 anos ± 1,8 anos) permaneceram em decúbito dorsal, com respiração espontânea por 20 minutos. A frequência cardíaca foi registrada batimento a batimento e a análise da VFC foi realizada pela técnica de Dimensão Fractal Higuchi. RESULTADOS: TDAH promoveu um aumento na Dimensão Fractal Higuchi. O valor ideal de Kmax foi 10. CONCLUSÃO: O TDAH alterou significantemente a modulação autonômica cardíaca, como demonstrado pela Dimensão Fractal Higuchi da VFC. Assim, pode-se afirmar que crianças com TDAH apresentaram aumento das respostas caóticas neste tipo de análise da modulação autonômica cardíaca.


Subject(s)
Humans , Male , Female , Child , Adolescent , Attention Deficit Disorder with Hyperactivity , Autonomic Nervous System , Cognition , Heart Rate , Arrhythmias, Cardiac , Child Psychiatry , Therapeutics
12.
Rev. bras. crescimento desenvolv. hum ; 26(2): 162-173, 2016. graf, tab
Article in English | LILACS | ID: lil-797807

ABSTRACT

INTRODUCTION: Fetal heart rate and its variability during the course of gestation have been extensively researched. The overall reduction in heart rate and increase in fetal HRV is associated with fetal growth and the increase in neural integration. The increased complexity of the demands on the cardiovascular system leads to more variation in the temporal course of the heart rate which has been shown to be reflected in measures of complexity. The aim of this work was to investigate novel complexity measures with respect to their ability to quantify changes over gestational age in individual fetuses consistently and in a stable manner. METHODS: We examined 215 fetal magnetocardiograms (FMCG), each of 5 min duration, in 11 fetuses during the second and third trimesters (at least 10 data sets per fetus). From the FMCG we determined the fetal RR beat durations. For each 5 min time-series of RR intervals we then calculated Shannon entropy, high spectral entropy, high spectral Detrended Fluctuation Analysis, spectral Multi-Taper Method as well as the standard deviation and two commonly used complexity measures: Approximate Entropy and Sample Entropy. For each subject and HRV measure, we performed regression analysis with respect to gestational age. The coefficient of determination R² was used to estimate 'goodness-of-fit', the slope of the regression indicated the strength of the individual dependency on gestational age. RESULTS: We found that the new complexity measures do not outperform ApEn. CONCLUSION: This study has now rejected the hypothesis that the spectral complexity measures outperform those applied previously.


INTRODUÇÃO: A freqüência cardíaca fetal e da sua variabilidade durante o curso da gestação têm sido extensivamente pesquisada. A redução global da frequência cardíaca e aumento da VFC fetal está associada com o crescimento fetal e aumento da integração neural. O aumento da complexidade das exigências sobre o sistema cardiovascular conduz a uma maior variação no decurso temporal da frequência cardíaca o que foi mostrado para reflectir-se medidas de complexidade. O objetivo deste trabalho foi investigar medidas de complexidade novos em relação à sua capacidade de quantificar as mudanças ao longo da idade gestacional em fetos individuais de forma consistente e de forma estável. MÉTODO: Foram examinados 215 magnetocardiograms fetais (FMCG), cada um dos 5 min de duração, em 11 fetos durante o segundo e terceiro trimestres (pelo menos 10 conjuntos de dados por feto). A partir do grande consumo determinamos as durações RR batimento fetais. Para cada série temporal 5 min dos intervalos RR então calculada Shannon entropia, alta entropia espectral, alta espectral Destendenciada Análise Flutuação, espectral Multi-Taper Método, bem como o desvio padrão e duas medidas de complexidade comumente utilizados: aproximado Entropia e Amostra Entropia. Para cada medida assunto e HRV, foi realizada análise de regressão em relação à idade gestacional. O coeficiente de determinação R² foi usada para estimar a "o bem-of-fit", a inclinação da regressão indicou a força do indivíduo dependência da idade gestacional. RESULTADOS: Verificou-se que as novas medidas de complexidade não superar ApEn. CONCLUSÃO: Este estudo agora rejeitou a hipótese de que as medidas de complexidade espectrais superar os aplicados anteriormente.


Subject(s)
Humans , Male , Female , Cardiovascular System , Entropy , Fetal Development , Fetus , Gestational Age , Heart Rate, Fetal , Pregnancy
13.
MedicalExpress (São Paulo, Online) ; 2(5)Sept.-Oct. 2015. tab, graf
Article in English | LILACS | ID: lil-776672

ABSTRACT

OBJECTIVE: Auditory stimulation with relaxing style music can improve cardiac autonomic regulation in subjects treated with a cardio-toxic medication. We assess the acute effect of heavy metal music on cardiac autonomic regulation, through novel high spectral chaotic global analysis techniques: (a) high spectral detrended fluctuation, (b) high spectral entropy (c) spectral multi-taper method. METHOD: We investigated young adult women between 18 and 30 years old exposed to heavy metal (75-84 dB) music for 20 min. Normality tests were applied: (i) Anderson-Darling, (ii) Ryan-Joiner (similar to Shapiro-Wilk); (iii) Lilliefors for low number of subjects. They all indicated a non-normal data distribution. Consequently we applied the Kruskal-Wallis non-parametric test. Also because of the small population, we used a broader than usual level of significance (critical p = 0.1). RESULTS: The application of the three tests for normality and the non-parametric test of significance by the Kruskal-Wallis technique showed that acute musical auditory stimulation with heavy metal music lead to a significant increase (p < 0.07) in one of the seven combinations of chaotic globals. The most significant combination of chaotic globals is the Chaos Forward Parameter One (CFP1), which includes all three studied chaotic globals (high spectral detrended fluctuation, high spectral entropy, spectral multi-taper method). We found significantly increased values during musical auditory stimulation for this specific CFP1. CONCLUSION: It is suggested that acute musical stimulation with heavy metal influences cardiac autonomic regulation at a more complex level than previously reported and that this may be beneficial to heart function.


OBJETIVO: A estimulação auditiva com música relaxante pode melhorar a regulação autonômica cardíaca em indivíduos tratados com um medicamento cardiotóxica. Avaliamos o efeito agudo de música heavy metal sobre a regulação autonômica cardíaca, por meio de novas técnicas de análise, ditas globalmente caóticas de espectrais altos: (a) high spectral detrended fluctuation, (b) high spectral entropy (c) spectral multi-taper method. MÉTODO: Estudamos mulheres jovens entre 18 e 30 anos de idade expostas a música heavy metal (75-84 dB) durante 20 min. Foram aplicados os seguintes testes de normalidade: (i) Anderson-Darling, (ii) Ryan-Joiner (similhante ao de Shapiro-Wilk); (iii) Lilliefors para baixo número de indivíduos. Todos indicaram que os dados obtidos apresentavam distribuição não-normal. Consequentemente foi aplicado o teste não-paramétrico de Kruskal-Wallis. Por causa da pequena população, utilizou-se um nível de significância mais amplo do que o habitual (p crítico = 0,1). RESULTADOS: A aplicação dos três testes para normalidade e o teste não-paramétrico de significância pela técnica de Kruskal-Wallis mostrou que a estimulação auditiva musical aguda com metais pesados produziu um aumento significativo (p < 0,07) em uma das sete combinações de globais caóticos. A combinação de globais caóticos que é mais importante é a "Chaos Forward Paremeter one" (VFP1) na qual se manifestam todos os três globais caóticos aplicados (high spectral detrended fluctuation, high spectral entropy, spectral multi-taper method). Encontramos um aumento significativo durante a estimulação auditiva musical para este parâmetro específico. CONCLUSÃO: Sugere-se que a estimulação musical aguda com heavy metal influencia a regulação autonômica cardíaca em um nível mais complexo e pode ser benéfica para a função cardíaca.


Subject(s)
Humans , Female , Adult , Spectrum Analysis/methods , Autonomic Nervous System , Acoustic Stimulation , Cardiovascular System , Music
14.
Rev. mex. trastor. aliment ; 6(1): 51-63, tab
Article in English | LILACS-Express | LILACS | ID: lil-773417

ABSTRACT

Disordered eating behaviors (DEB) such as dieting, fasting, laxatives or diuretics abuse, self-induced vomiting and binge eating may lead serious physiological and psychological consequences in individuals. Epidemiological data helps to the understanding of the magnitude of this problem within population; however point prevalence rates and the trend of DEB are still a subject of constant debate. Therefore the aim of this study is to systematically review empirical studies that have estimated the prevalence of DEB in women and provide some methodological considerations for future epidemiological studies. The search of articles was made through MEDLINE and SCIENCE DIRECT databases from 2000 to 2013. According to inclusion and exclusion criteria 20 studies were reviewed. Results yielded that the point prevalence range of dieting (0.6-51.7%), fasting (2.1-18.5%) and binge eating (1.2-17.3%) are higher than purgative behaviors (0-11%). However finding a trend in DEB over time was difficult since methodologies were significantly different. Methodological considerations for future research in DEB are proposed.


Las conductas alimentarias de riesgo (CAR) de los trastornos alimentarios, tales como dieta, ayuno, abuso de laxantes o diuréticos, vómito autoinducido y atracón, pueden causar graves consecuencias fisiológicas y psicológicas en el individuo. Los datos epidemiológicos ayudan a la comprensión de la magnitud de este problema en la población, sin embargo las tasas de prevalencia puntual y la tendencia de las CAR aún son tema de constante debate. Por lo tanto, el objetivo del presente estudio es revisar sistemáticamente estudios empíricos que estimen la prevalencia de las CAR en mujeres y proveer consideraciones metodológicas para futura investigación epidemiológica. La búsqueda de artículos fue a través de las bases de datos de MEDLINE y SCIENCEDIRECT de 2000 a 2013. Con base en los criterios de inclusión y exclusión 20 estudios fueron analizados. Los resultados arrojaron que el rango de la prevalencia puntual para dieta (0,6-51,7%), ayuno (2,1-18,5%) y atracón (1,2-17,3%) son mayores que el de las conductas purgativas (0-11%). Sin embargo, fue difícil encontrar una tendencia en las CAR a través del tiempo debido a que las metodologías utilizadas fueron significativamente diferentes. Se proponen consideraciones metodológicas para futuras investigaciones en CAR.

15.
Rev. bras. crescimento desenvolv. hum ; 25(1): 82-88, 2015. graf, tab
Article in English | LILACS | ID: lil-747950

ABSTRACT

OBJECTIVE: this study aimed to assess the heart rate dynamics in young obese subjects by novel chaotic globals to HRV METHODS: eighty-six young subjects were distributed in two equal groups (n = 43) according to the nutritional status: obese and control following Body Mass Index. For the analysis of HRV indexes, the heart rate was recorded heartbeat to heartbeat with the young resting in dorsal (prone) position for 30 minutes RESULTS: after Anderson-Darling and Lilliefors tests, the data was deemed non-normal. So, Kruskal-Wallis test of significance was applied for the statistical analysis, level set at (p < 0.01). Principal Component Analysis (PCA) identified two components represented 100% of total variance. The algorithm which applies all three parameters is suggested as the most influential and statistically very significant at the level (p < 0.001); it also elevates the chaotic response CONCLUSION: youth obesity increases the chaotic response. The reasons for the study include quantitative assessment to allow effective dietary, pharmacological or even surgical intervention in the condition.


Subject(s)
Humans , Male , Female , Adolescent , Adolescent , Body Mass Index , Heart Rate , Nutritional Status , Obesity , Pharmacology, Clinical , Surgical Procedures, Operative , Autonomic Nervous System , Evaluation Studies as Topic
16.
Rev. bras. crescimento desenvolv. hum ; 24(3): 243-248, 2014. graf, tab
Article in English | LILACS | ID: lil-744177

ABSTRACT

The aim of this study is to assess the risk of dynamical diseases in malnourished children. This is achieved by the application of novel chaotic global techniques to the RR-intervals of the electrocardiogram (ECG) in the cohort. Heart Rate Variability (HRV) is an inexpensive and non-invasive tool to measure the autonomic impulses. Here there has been a decrease in chaotic response of HRV. Seventy children were divided into equal groups and the HRV monitored for 20-25 minutes. The Chaos Forward Parameter (CFP) which applies all three chaotic global parameters is suggested to be the most robust algorithm. These three parameters are high spectral entropy (hsEntropy), high spectral detrended fluctuation analysis (hsDFA) and spectral multi-taper method (sMTM)...


O objetivo deste estudo é avaliar o risco de doenças dinâmicas em crianças desnutridas. Isto é feito por meio da aplicação de novas técnicas caóticas globais para os intervalos R-R do ECG. A variabilidade da frequência cardíaca (VFC) é uma ferramenta de baixo custo e não-invasiva que mensura os impulsos autonômicos. Na desnutrição ocorreu uma diminuição na resposta caótica da VFC. Setenta crianças foram divididas em grupos iguais e a VFC foi monitorada por 20 a 25 minutos. O parâmetro caótico avançado (CFP), que utiliza os três parâmetros caóticos globais é o algoritmo mais robusto. Estes três parâmetros são: alta entropia espectral (hsEntropia), análise da alta flutuação depurada espectral (hsDFA) e método espectral multi-taper (sMTM)...


Subject(s)
Humans , Male , Female , Child , Child , Child Nutrition Disorders , Heart Rate , Entropy , Nonlinear Dynamics , Data Interpretation, Statistical
17.
Rev. bras. crescimento desenvolv. hum ; 24(1): 24-30, 2014. graf, tab
Article in English | LILACS | ID: lil-717753

ABSTRACT

The aim of the study is to analyze heart rate dynamics in obese children by measures of HRV. HRV is a simple and non-invasive measure of autonomic impulses. 94 children of mixed gender aged eight to twelve years were divided into two equal groups based on body mass index: obese and normal weight range. HRV was monitored in the dorsal decubitus position for 20 minutes. After tests of normality, Kruskal Wallis was applied for the statistical analysis, with the level of significance set at (p < 0.05). Regarding the application of Principal Component Analysis the first two components represent 99.4% of total variance. The obese children exhibited in heart frequency dynamics associated to an increase in the Chaos Forward Parameter. The Chaos Forward Parameter which applies all three chaotic global parameters is suggested to be the most robust algorithm. Obesity in children can be termed a dynamical condition but it increases the chaotic response...


Subject(s)
Humans , Male , Female , Child , Child , Chronic Disease , Electrocardiography , Heart Rate , Pediatric Obesity/complications , Pediatric Obesity , Data Interpretation, Statistical
18.
Rev. mex. trastor. aliment ; 1(1): 1-26, Jan.-June 2010. tab
Article in English | LILACS-Express | LILACS | ID: lil-714474

ABSTRACT

Therapist competency is fundamental to the success in treating most psychological disorders. However, the skills required to effectively treat eating disorders may be more demanding than many other problems, because competency requires mastery of considerable educational information about physical complications associated with eating-disorder symptoms and chronic weight suppression. The cognitive-behavioral model of treatment has become well-defined in recent years; however, the mark for therapist competency continues to rise as the knowledge base has expanded with the high level of clinical and research interest in eating disorders. The guidelines provided in this paper are intended to provide a springboard for the training and supervision to improve patient care.


La competencia del terapeuta es fundamental para el éxito en el tratamiento de los Trastornos Psicológicos. Sin embargo, las habilidades que se requieren para tratar eficazmente los Trastornos del Comportamiento Alimentarios pueden ser más demandantes que para otros problemas, porque la competencia requiere del dominio de considerable información educativa acerca de las complicaciones físicas asociadas con los síntomas de los Trastornos Alimentarios y la supresión crónica de peso. El modelo de tratamiento cognitivo-conductual se ha convertido en el mejor definido en recientes años, sin embargo, el marco de la competencia del terapeuta continúa aumentando, dado que, la base de conocimientos se ha ampliado con el alto nivel de interés en la investigación clínica y en los trastornos alimentarios. Las directrices que proporciona este artículo tiene objetivo servir de trampolín para la formación y supervisión para mejorar la atención al paciente.

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