Is the algorithm used to process heart rate variability data clinically relevant? Analysis in male adolescents

OBJECTIVE: To analyze whether the algorithm used for the heart rate variability assessment (fast Fourier transform versus autoregressive methods) influenced its association with cardiovascular risk factors in male adolescents. METHODS: This cross-sectional study included 1,152 male adolescents (aged 14 to 19 years). The low frequency, high frequency components (absolute numbers and normalized units), low frequency/high frequency ratio, and total power of heart rate variability parameters were obtained using the fast Fourier transform and autoregressive methods, while the adolescents were resting in a supine position. RESULTS: All heart rate variability parameters calculated from both methods were different (p<0.05). However, a low effect size (<0.1) was found for all parameters. The intra-class correlation between methods ranged from 0.96 to 0.99, whereas the variation coefficient ranged from 7.4 to 14.8%. Furthermore, waist circumference was negatively associated with high frequency, and positively associated with low frequency and sympatovagal balance (p<0.001 for both fast Fourier transform and autoregressive methods in all associations). Systolic blood pressure was negatively associated with total power and high frequency, whereas it was positively associated with low frequency and sympatovagal balance (p<0.001 for both fast Fourier transform and autoregressive methods in all associations). Body mass index was negatively associated with high frequency, while it was positively associated with low frequency and sympatovagal balance (p values ranged from <0.001 to 0.007). CONCLUSION: There are significant differences in heart rate variability parameters obtained with the fast Fourier transform and autoregressive methods in male adolescent; however, these differences are not clinically significant. OBJETIVO: Analisar se o algoritmo usado para avaliação da variabilidade da frequência cardíaca (transformada rápida de Fourier versus autoregressivo) influencia em sua associação com fatores de risco cardiovascular adolescentes do gênero masculino. MÉTODOS: Estudo transversal, que incluiu 1.152 adolescentes do gênero masculino (14 a 19 anos). Componentes de baixa e alta frequência (absolutos e unidades normalizadas), razão componente de baixa frequência/componente de alta frequência e poder total da variabilidade da frequência cardíaca foram obtidos em repouso, na posição supina, usando os métodos transformada rápida de Fourier e autorregressivo. RESULTADOS: Todos os parâmetros da variabilidade da frequência cardíaca para ambos os métodos foram diferentes (p<0,05). Entretanto, um pequeno tamanho do efeito (<0,1) foi observado para todos os parâmetros. Os coeficientes de correlação intraclasse entre os métodos variaram de 0,96 a 0,99, enquanto os coeficientes de variação foram de 7,4 a 14,8%. A circunferência abdominal foi negativamente associada com o componente de alta frequência, e positivamente associada com o componente de baixa frequência e o balanço simpatovagal (p<0,001 para a transformada rápida de Fourier e o autorregressivo em todas as associações). A pressão arterial sistólica foi negativamente associada com o poder total e o componente de alta frequência, enquanto foi positivamente associada com o componente de baixa frequência e o balanço simpatovagal (p<0,001 para a transformada rápida de Fourier e o autorregressivo em todas as associações). O índice de massa corporal foi negativamente associado com o componente de alta frequência, enquanto foi positivamente associado com o componente de baixa frequência e o balanço simpatovagal (valores de p variando de <0,001 a 0,007). CONCLUSÃO: Houve diferenças significantes nos parâmetros da variabilidade da frequência cardíaca obtidos com os métodos transformada rápida de Fourier e autorregressivo em adolescentes masculinos, mas essas diferenças não foram clinicamente significativas

Impact of hypertension on arterial stiffness and cardiac autonomic modulation in patients with peripheral artery disease: a cross-sectional study

To examine the impact of hypertension on cardiovascular health in patients with symptomatic peripheral artery disease and to identify factors associated with uncontrolled hypertension. A cross-sectional study including 251 patients with symptomatic peripheral artery disease (63.9% males, mean age 67±10 years). Following hypertension diagnosis, blood pressure was measured to determine control of hypertension. Arterial stiffness (carotid-femoral pulse wave velocity) and cardiac autonomic modulation (sympathovagal balance) were assessed. Hypertension was associated with higher carotid-femoral pulse wave velocity, regardless of sex, age, ankle-brachial index, body mass index, walking capacity, heart rate, or comorbidities (ß=2.59±0.76m/s, b=0.318, p=0.003). Patients with systolic blood pressure ≥120mmHg had higher carotid-femoral pulse wave velocity values than normotensive individuals, and hypertensive patients with systolic blood pressure of ≤119mmHg (normotensive: 7.6±2.4m/s=≤119mmHg: 8.1±2.2m/s 120-129mmHg:9.8±2.6m/s=≥130mmHg: 9.9±2.9m/s, p0.05). Hypertensive patients with symptomatic peripheral artery disease have increased arterial stiffness. Arterial stiffness is even greater in patients with uncontrolled high blood pressure

Relationship between propulsive force of the arm, body composition and isokinetic muscle strength indicators in surfers

This study aimed to evaluate the potential relationship between body composition (percentage of fat mass (FM %), fat mass and lean mass), muscle function (e.g., muscles; deltoid side and front, pectoralis major and teres major) and the propulsive force of the arm (PFA). Sixteen competitive surfers (29.1 ± 7.3 years; 1.72 ± 0.06 m; 74.2 ± 1.4 kg) were assessed for height, body mass, body composition (dual-energy-DXA), muscle function and PFA. Pearson correlation analyses were used to verify the relationship between all variables. An inverse correlations were found between PFA and isokinetic parameters to 60o/s: external rotation (peak torque: r = -0.71; p = 0.014; total work: r = -0.75; p = 0.007; power: r = -0.72; p = 0.011) and internal rotation (peak torque: r = -0.61; p = 0.045; total work: r = -0.73; p = 0.010; power: r = -0.61; p = 0.045) and 300o/s: external rotation (peak torque: r = -0.79; p = 0.003; total work: r = -0.84; p0.05). Although correlations do not imply cause and effect, PFA is not correlated with body composition in surfers and these relationships are inversely related to the parameters of muscle function

Trends in television and computer/videogame use and total screen time in high school students from Caruaru city, Pernambuco, Brazil: A repeated panel study between 2007 and 2012

Abstract Aim: to analyze the pattern and trends of use of screen-based devices and associated factors from two surveys conducted on public high school students in Caruaru-PE. Methods: two representative school-based cross-sectional surveys conducted in 2007 (n=600) and 2012 (n=715) on high school students (15-20 years old). The time of exposure to television (TV) and computer/videogames PC/VG was obtained through a validated questionnaire, and ≥3 hours/day was considered as being excessive exposure. The independent variables were socioeconomic status, school related, and physical activity. Crude and adjusted binary logistic regression were employed to examine the factors associated with screen time. The statistical significance was set at p<0.05. Results: There was a significant reduction in TV time on weekdays and total weekly, but no change in the prevalence of excessive exposure. The proportion of exposure to PC/VG of ≥3 hours/day increased 182.5% on weekdays and 69.5% on weekends (p <0.05). In 2007, being physically active was the only protection factor for excessive exposure to total screen time. In 2012, girls presented less chance of excessive exposure to all screen-based devices and total screen time. Other protective factors were studying at night and being physically active (PC/VG time), while residing in an urban area [OR 5.03(2.77-7.41)] and having higher family income [OR 1.55(1.04-2.30)] were risk factors. Conclusion: Significant and important changes in the time trends and pattern of use PC/VG were observed during the interval of 5 years. This rapid increase could be associated with increased family income and improved access to these devices, driven by technological developments

Cardiac Autonomic Modulation Is Associated with Arterial Stiffness in Patients with Symptomatic Peripheral Artery Disease

BACKGROUND: The objective of this study was to analyze the association between cardiac autonomic modulation and arterial stiffness in patients with peripheral artery disease (PAD). METHODS: This cross-sectional study included one hundred fourteen patients with symptomatic PAD (67.5% men; 65 ± 7 years; body mass index: 26.8 ± 4.5 kg/m2). Heart rate variability (HRV) was measured within time (standard deviation of all RR intervals [beat to beat heart interval] [SDNN], root mean square of the successive differences between adjacent normal RR intervals [RMSSD], and the proportion of successive RR intervals that differed by more than 50 msec [pNN50]) and frequency (low frequency [LF] and high frequency [HF]) domains. Arterial stiffness was assessed by carotid-femoral pulse wave velocity (cfPWV). Crude and adjusted linear regression analyses examined the relationship between HRV and cfPWV. RESULTS: Nonsignificant crude associations were identified among cfPWV and RMSSD (P = 0.181), SDNN (P = 0.105), pNN50 (P = 0.087), LF (P = 0.376), HF (P = 0.175), and LF/HF ratio (P = 0.426). After adjustments for age, sex, smoking, body mass index, ankle-brachial index, and use of beta-blockers, significant associations were identified among cfPWV and RMSSD (P = 0.037), SDNN (P = 0.049), and pNN50 (P = 0.049). CONCLUSIONS: Cardiac autonomic modulation was significantly associated with arterial stiffness in patients with PAD after adjustment for confounding factors. This relationship may contribute to the enhanced cardiovascular disease risk for PAD patients and provides a target for strategies to improve patient clinical outcomes

Association between handgrip strength and vascular function in patients with hypertension

Background: Increased handgrip strength has been associated with lower cardiovascular and non-cardiovascular mortality in different populations. In patients with hypertension, arterial stiffness relates to cardiovascular mortality. However, whether muscle strength is associated with arterial stiffness in hypertensives is unknown. Thus, the objective of this study was to analyze the association between handgrip strength and arterial stiffness parameters in hypertensive patients. Methods: Seventy-two hypertensive patients completed all evaluations and were included in the analysis. The ambulatory arterial stiffness index (AASI) was obtained based on 24-h ambulatory blood pressure monitoring. Carotid-femoral pulse wave velocity (cfPWV), and reflected wave indicator (AIx and AIx@75) were estimated using applanation tonometry technique, whereas handgrip strength test was performed using a digital dynamometer. Crude and adjusted linear regression models were performed. Results: The crude analysis revealed a negative association between handgrip strength and AASI (b = −0.41, p = 0.002) and AIx (b = −0.49, p  0.05). Conclusion: Handgrip strength is negatively associated with AASI and AIx@75, but not with AIx and cfPWV in hypertensive patients

Physical activity, sedentary behavior, and sleep measured by smartwatch: a scoping review protocol

This scoping review will identify information about the extension and scope of evidence on the use of smartwatches to objectively measure physical activity, sedentary behavior and/or sleep regardless of study design (i.e., cross-sectional, longitudinal, randomized clinical trials), purpose of measurement (i.e., outcome, exposure, self-monitoring of interventions, validation), context (i.e., laboratory, school, free-living condition), and population (i.e., children, adolescents, adults, clinical population). This protocol describes a scoping review that aims to filling out this literature research gap. This will follow the Preferred Reporting Items for Systematic reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR). Studies will be included whether they use smartwatches to objectively measure PA, SB and/or sleep in children, adolescents, adults and older adults. Only studies published after 2013 will be considered eligible. No language filter will be applied. Searches will be carried out on Medline; Scopus; Web of Science; IEEE Xplore Digital Library; Scielo; Health Technology Assessment Database; Cochrane clinical trials and clinical trial repositories. The screening and data extraction will be performed independently by two authors who had previous experience in reviews and technologies. The synthesis of the results will follow the JBI framework for extracting the results in scoping reviews. Our hypoteshis is that the results will identify insights concerning the extent and scope of use smartwatches to objectively measures of PA, SB and sleep that will be useful for research and end-user communities

Physical Activity and Heart Rate Variability in Adolescents with Abdominal Obesity

Physical activity is a protective factor for autonomic dysfunction. However, whether this occurs in adolescents with abdominal obesity is still unclear. Thus, the aim of this study was to analyze the association between physical activity and heart rate variability (HRV) in adolescents with and without abdominal obesity. This cross-sectional study included 1152 boys (age: 17 +/- 1 years). HRV measures of time (root mean square of the squared differences between adjacent normal RR intervals-RMSSD and the percentage of adjacent intervals over 50 ms-PNN50) and frequency domains (balance sympathetic-vagal-LF/HF) were evaluated, as well as total physical activity, commuting physical activity, leisure-time physical activity, and abdominal obesity. All physical activity domains were associated with better RMSSD, PNN50, and LF/HF in normal weight adolescents (p < 0.05), whereas in adolescents with abdominal obesity only leisure-time physical activity was associated with better PNN50 (b = 0.174, p = 0.035) independent of age, period of the day, body mass index, and blood pressure. In conclusion, higher leisure-time physical activity, but not total and commuting physical activity levels, was associated with improved HRV in adolescents with abdominal obesity.Brazilian National Council for Scientific and Technological Development (CNPq)Brazilian Federal Agency for Support and Evaluation of Graduate Education (CAPES)ASCES Coll, Grp Res Hlth & Sport, Caruaru, PE, BrazilUniv Sao Paulo, Sch Phys Educ & Sport, Exercise Hemodynam Lab, Ave Prof Melo Moraes 65, BR-05508030 Sao Paulo, SP, BrazilUniv Pernambuco, Associate Grad Program Phys Educ, Recife, PE, BrazilUniv Paulista State UNESP, Dept Phys Educ, Lab Invest Exercise LIVE, Sao Paulo, SP, BrazilUniv Pernambuco, Adolescent Hlth, Camaragibe, PE, BrazilUniv Fed Sao Paulo, Dept Human Movement Sci, Santos, BrazilUniv Nove Julho, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Dept Human Movement Sci, Santos, BrazilCNPq: 481067/2010-8]CAPESWeb of Scienc

Anthropometric parameters as predictors of muscle mass in elderly women

<p>The aims of study were to analyze the relationship between muscle mass and anthropometric parameters in elderly women and to develop a mathematical model to predict muscle mass based on anthropometric parameters. The study included 63 elderly women (71.4 ± 4.4 years). Body weight, height, arm, waist, hip and calf circumferences were measured. Muscle mass was estimated using a densitometry. The muscle mass index was calculated using the equation (muscle mass index = muscle mass [kg] / height [m]²). A significant correlation was found between muscle mass and body weight (r = 0.782), arm (r=0.688), waist (r=0.467), hip (r=0.629) and calf circumferences (r=0.592) with p&lt;0.05 for all. Regression analysis indicated that body mass and calf circumference were independent predictors of muscle mass (r=0.81, r²=0.65, F=55.7). The prediction model obtained was muscle mass (kg)=-0.543+(0.162*body mass)+(0.151*calf circumference). No differences were observed between the amount of muscle mass and muscle mass index estimated by densitometry and by equation (p&gt;0.05). The results of this study indicated that body mass, body mass index, arm, waist, hip and calf circumferences are related to muscle mass elderly women. The muscle mass can be adequately predicted based on data from body mass and calf circumference.</p

Factors Associated to Arterial Stiffness in Patients With Symptomatic Peripheral Artery Disease

BACKGROUND: The aim of this study was to identify the clinical factors associated with arterial stiffness in patients with symptomatic peripheral artery disease. METHODS: In this cross-sectional study, 181 patients (67% men; mean aged 66 ± 9 years) were recruited and had their central arterial stiffness assessed by carotid-femoral pulse wave velocity (cf-PWV). Clinical characteristics are sociodemographic data, body mass index, comorbid conditions, and walking capacity. RESULTS: Multiple linear regression analysis showed that age (b = 0.182, P = 0.032), body mass index (b = 0.254, P = 0.002), and mean blood pressure (b = 0.249, P = 0.021) were positively associated with cf-PWV. CONCLUSIONS: Our results showed that the aging, elevated body mass index, and higher blood pressure are clinical factors associated with increased arterial stiffness in patients with peripheral artery disease