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1.
Prog Cardiovasc Dis ; 83: 29-35, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38428786

RESUMO

Currently, assessing physical activity (PA) and cardiorespiratory fitness in healthcare settings and supporting patients on their journey toward active living is not a standard of practice in the US, although significant progress is underway. This paper summarizes the foundational as well as supporting public policies necessary to make PA assessment, prescription, and referral a standard of care in the US healthcare system to support active living for all. Measure standardization and healthcare integration will be supported by digital health and public private partnerships, as well as payer strategies and quality and performance incentives. The policy and systems change effort, currently being led by the Physical Activity Alliance's "It's Time to Move" initiative, will improve patient care and the ability to monitor PA levels across the US population, filling in gaps in current national public health surveillance systems. Having patient data available will also allow for additional research that elucidates the relationship between PA and overall health and well-being.


Assuntos
Exercício Físico , Humanos , Política de Saúde , Estados Unidos , Política Pública , Aptidão Cardiorrespiratória , Estilo de Vida Saudável , Promoção da Saúde
2.
Health Res Policy Syst ; 22(1): 27, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378597

RESUMO

Advocacy organizations can play a crucial role in evaluating whether legislation or regulation has had its intended effect by supporting robust public policy implementation and outcome evaluation. The American Heart Association, working with expert advisors, has developed a framework for effective evaluation that can be used by advocacy organizations, in partnership with researchers, public health agencies, funders, and policy makers to assess the health and equity impact of legislation and regulation over time. Advocacy organizations can use parts of this framework to evaluate the impact of policies relevant to their own advocacy and public policy efforts and inform policy development and guide their organizational resource allocation. Ultimately, working in partnership, advocacy organizations can help bring capacity, commitment and funding to this important implementation and outcome evaluation work that informs impactful public policy for equitable population health and well-being.


Assuntos
Organizações , Política Pública , Estados Unidos , Humanos , Formulação de Políticas , Avaliação de Resultados em Cuidados de Saúde , Saúde Pública , Política de Saúde
3.
Prog Cardiovasc Dis ; 76: 49-56, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36690285

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic had a transformational impact on public policy as governments played a leading role, working alongside and coordinating with business/industry, healthcare, public health, education, transportation, researchers, non-governmental organizations, philanthropy, and media/communications. This paper summarizes the impact of the pandemic on different areas of public policy affecting healthy living and cardiovascular health including prevention (i.e., nutrition, physical activity, air quality, tobacco use), risk factors for chronic disease (hypertension, diabetes, obesity, substance abuse), access to health care, care delivery and payment reform, telehealth and digital health, research, and employment policy. The paper underscores where public policy is evolving and where there are needs for future evidence base to inform policy development, and the intersections between the public and private sectors across the policy continuum. There is a continued need for global multi-sector coordination to optimize population health.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Atenção à Saúde , Obesidade , Política Pública , Estilo de Vida Saudável
4.
Artigo em Inglês | MEDLINE | ID: mdl-34831690

RESUMO

BACKGROUND: North Americans report insufficient moderate-to-vigorous physical activity (MVPA) and ample sedentary behaviors (SBs), suggesting possible barriers to an active lifestyle. This study compared self-reported MVPA and SB before and during COVID-19 "Stay-at-Home" restrictions as a potential barrier across North America. METHODS: Questionnaires were distributed from 21 April to 9 May 2020. ANOVAs compared data overall and by group (age, sex, race, income, education, employment status). RESULTS: During restrictions, 51.4% (n = 687) of the 1336 responses (991 female, 1187 Caucasian, 634 18-29 years) shifted to work from home and 12.1% (n = 162) lost their job. Overall, during restrictions, 8.3% (n = 110) fewer reported work-related MVPA (-178.6 ± 20.9 min/week). Similarly, 28.0% (n = 374) fewer reported travel-related MVPA, especially females and younger age groups. While the 7.3% (n = 98) fewer reporting recreational MVPA was not statistically significant (-30.4 ± 11.5 min/week), there was an increase in SB (+94.9 ± 4.1 min/week) in all groups, except the oldest age group (70+ years). Locomotive activities and fitness class remained the predominant MVPA mode. Of those reportedly using facilities (68%; n = 709) before COVID, 31.3% (n = 418) would not return due to it "being unsafe". CONCLUSION: While barriers related to pandemic restrictions had a negative short-term impact on MVPA and SB in North America, the long-term impact is unknown.


Assuntos
COVID-19 , Comportamento Sedentário , Acelerometria , Idoso , Emprego , Exercício Físico , Feminino , Humanos , SARS-CoV-2 , Viagem , Doença Relacionada a Viagens
5.
J Pers Oriented Res ; 7(2): 78-87, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35070173

RESUMO

The purpose of this study was to investigate within- and between-person associations between sleep and subsequent goal setting in adolescents. We conducted an intensive repeated measures longitudinal study to assess intra- and inter-individual associations between sleep and goal setting and potential moderators of such associations. Thirty-nine seventh through 12th graders reported on their sleep quality and propensity to set goals in their daily lives several times per week for approximately four months. We used a combination of multilevel modeling with time-varying covariates and centering techniques to partition within- and between-person variance. We found significant and positive associations between sleep and goal setting within individuals, but no such associations between individuals. That is, students were more likely to set goals for their work after getting a good night's sleep relative to their own average sleep quality, but getting good sleep on average relative to other individuals showed no association with average goal setting. These relationships were not moderated by participant age, gender, or sociodemographic status as indexed by maternal education. Differences in average sleep between adolescents matters less for their propensity to set goals than whether they experienced better- or worse-than-usual sleep the previous night given their own average. This finding represents the first evidence documenting effects of sleep on goal setting, which is an important psychological precursor to many youth behavioral and achievement outcomes. Our findings highlight the individuality of sleep needs and point to new directions for sleep-related practice and policy aimed at youth.

6.
Heart Lung ; 50(1): 59-64, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32703623

RESUMO

BACKGROUND: Inadequate decongestion is common in hospitalized heart failure (HF) patients and may contribute to readmissions. Our purpose was to use remote dielectric sensing (ReDS) technology to measure lung congestion at discharge in patients admitted with acute HF and to see if a device-targeted intervention could reduce HF readmission rates. METHODS: We conducted a prospective pilot study of patients admitted with acute decompensated HF randomized to receive standard therapy or ReDS-guided therapy to determine the timing of hospital discharge based on the amount of lung congestion present after diuresis. ReDS measurement was performed for all patients once they were deemed ready for discharge. Patients in the treatment arm with residual lung congestion defined by ReDS ≥39% had HF consultation and further diuresis. RESULTS: Of 108 HF patients (50% male, age 73.6 ±â€¯12.6 years, BMI 29.3 ±â€¯4.3 kg/m2, EF 38.5 ±â€¯15.1%, BNP 1138 ±â€¯987 pg/mL), 32% demonstrated residual lung congestion at the time of proposed hospital discharge. ReDS guided therapy triggered additional diuresis in 30% (18/60) of the patients in the treatment arm (average weight loss 5.6 pounds, p = 0.02). 30-day HF readmission rates were similar in the treatment and the control arms (1.7% vs 4.2%; p = 0.44). Patients discharged as planned with residual lung congestion with ReDS ≥39% had higher 30-day readmission rate compared to patients who were adequately decongested at discharge with ReDS <39% (11.8% vs. 1.4%, p = 0.03). CONCLUSION: In our single-center cohort, ReDS testing demonstrated that 32% of HF patients deemed ready for discharge have clinically significant residual lung congestion which was associated with a higher risk of readmission. ReDS-guided management was associated with significant decongestion but not a reduction in HF readmissions in this sample.


Assuntos
Insuficiência Cardíaca , Alta do Paciente , Idoso , Idoso de 80 Anos ou mais , Feminino , Insuficiência Cardíaca/terapia , Humanos , Pulmão , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente , Projetos Piloto , Estudos Prospectivos
7.
J Pers Oriented Res ; 6(2): 73-87, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33569153

RESUMO

Traditional variable-centered research on executive functions (EFs) often infers intraindividual development using group-based averages. Such a method masks meaningful individuality and involves the fallacy of equating group-level data with person-specific changes. We used an intensive longitudinal design to study idiographic executive function fluctuation among ten boys from Grade 4. Each of the participants completed between 33 and 43 measurement occasions (M = 38.8) across approximately three months. Data were collected remotely using a computerized short version of the Dimensional Change Card Sort task. Multi-group analyses of three participant pairs (Participants 5 and 3, 5 and 2, and 5 and 6) demonstrated that Participant 5 differed from Participants 3 and 2 in different ways but Participants 5 and 6 were similar in all comparisons. Dynamic structural equation modeling demonstrated unique individual trajectories, which were not represented by the trajectory of group-averages. Although more than half of the participants showed a negative association between EFs and inattention, two participants showed a positive association between EF and inattention. This study demonstrated meaningful person-specific trajectories of EFs, suggesting that future study should undertake the analysis of individual development before data-aggregation or generalization from aggregate statistics to individuals.

8.
Front Med (Lausanne) ; 6: 236, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31750307

RESUMO

Background: Age-related declines in physical function lead to decreased independence and higher healthcare costs. Individuals who meet the endurance and resistance exercise recommendations can improve their physical function and overall fitness, even into their ninth decade. However, most older adults do not exercise regularly, and the majority of those who do only perform one type of exercise, and in doing so are not getting the benefits of endurance or resistance exercise. Herein we present the study protocol for a randomized clinical trial that will investigate the potential for high-intensity interval training (HIIT) to improve maximal oxygen consumption, muscular power, and muscle volume (primary outcomes), as well as body composition, 6-min walk distance, and muscular strength and endurance (secondary outcomes). Methods and Analysis: This is a single-site, single-blinded, randomized clinical trial. A minimum of 24 and maximum of 30 subjects aged 60-75 that are generally healthy but insufficiently active will be randomized. After completion of baseline assessments, participants will be randomized in a 1:1:1 ratio to participate in one of three 12-week exercise programs: stationary bicycle HIIT, stationary bicycle moderate-intensity continuous training (MICT), or resistance training. Repeat assessments will be taken immediately post intervention. Discussion: This study will examine the potential for stationary bicycle HIIT to result in both cardiorespiratory and muscular adaptations in older adults. The results will provide important insights into the effectiveness of interval training, and potentially support a shift from volume-driven to intensity-driven exercise strategies for older adults. Clinical Trial Registration: This trial is registered with ClinicalTrials.gov (registration number: NCT03978572, date of registration June 7, 2019).

9.
Med Sci Sports Exerc ; 50(2): 369-374, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28902683

RESUMO

INTRODUCTION: Determination of exercise oscillatory ventilation (EOV) is subjective, and the interreviewer agreement has not been reported. The purposes of this study were, among patients with heart failure (HF), as follows: 1) to determine the interreviewer agreement for EOV and 2) to describe a novel, objective, and quantifiable measure of EOV. METHODS: This was a secondary analysis of the HEART Camp: Promoting Adherence to Exercise in Patients with Heart Failure study. EOV was determined through a blinded review by six individuals on the basis of their interpretation of the EOV literature. Interreviewer agreement was assessed using Fleiss kappa (κ). Final determination of EOV was based on agreement by four of the six reviewers. A new measure (ventilation dispersion index; VDI) was calculated for each test, and its ability to predict EOV was assessed with the receiver operator characteristics curve. RESULTS: Among 243 patients with HF (age, 60 ± 12 yr; 45% women), the interreviewer agreement for EOV was fair (κ = 0.303) with 10-s discrete data averages and significantly better, but only moderate (κ = 0.429) with 30-s rolling data averages. Prevalence rates of positive and indeterminate EOVs were 18% and 30% with the 10-s discrete averages and 14% and 13% with the 30-s rolling averages, respectively. VDI was strongly associated with EOV, with areas under the receiver operator characteristics curve of 0.852 to 0.890. CONCLUSIONS: Interreviewer agreement for EOV in patients with HF is fair to moderate, which can negatively affect risk stratification. VDI has strong predictive validity with EOV; as such, it might be a useful measure of prognosis in patients with HF.


Assuntos
Exercício Físico , Insuficiência Cardíaca/fisiopatologia , Ventilação Pulmonar , Respiração , Idoso , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
J Am Coll Cardiol ; 67(7): 780-9, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-26892413

RESUMO

BACKGROUND: Data from a cardiopulmonary exercise (CPX) test are used to determine prognosis in patients with chronic heart failure (HF). However, few published studies have simultaneously compared the relative prognostic strength of multiple CPX variables. OBJECTIVES: The study sought to describe the strength of the association among variables measured during a CPX test and all-cause mortality in patients with HF with reduced ejection fraction (HFrEF), including the influence of sex and patient effort, as measured by respiratory exchange ratio (RER). METHODS: Among patients (n = 2,100, 29% women) enrolled in the HF-ACTION (HF-A Controlled Trial Investigating Outcomes of exercise traiNing) trial, 10 CPX test variables measured at baseline (e.g., peak oxygen uptake [Vo2], exercise duration, percent predicted peak Vo2 [%ppVo2], ventilatory efficiency) were examined. RESULTS: Over a median follow-up of 32 months, there were 357 deaths. All CPX variables, except RER, were related to all-cause mortality (all p < 0.0001). Both %ppVo2 and exercise duration were equally able to predict (Wald chi-square: ∼141) and discriminate (c-index: 0.69) mortality. Peak Vo2 (ml·kg(-1)·min(-1)) was the strongest predictor of mortality among men (Wald chi-square: 129) and exercise duration among women (Wald chi-square: 41). Multivariable analyses showed that %ppVo2, exercise duration, and peak Vo2 (ml·kg(-1)·min(-1)) were similarly able to predict and discriminate mortality. In men, a 10% 1-year mortality rate corresponded to a peak Vo2 of 10.9 ml·kg(-1)·min(-1) versus 5.3 ml·kg(-1)·min(-1) in women. CONCLUSIONS: Peak Vo2, exercise duration, and % ppVo2 carried the strongest ability to predict and discriminate the likelihood of death in patients with HFrEF. The prognosis associated with a given peak Vo2 differed by sex. (Exercise Training Program to Improve Clinical Outcomes in Individuals With Congestive Heart Failure; NCT00047437).


Assuntos
Teste de Esforço/métodos , Insuficiência Cardíaca Sistólica/mortalidade , Volume Sistólico/fisiologia , Adulto , Idoso , Causas de Morte/tendências , Progressão da Doença , Feminino , Seguimentos , Insuficiência Cardíaca Sistólica/diagnóstico , Insuficiência Cardíaca Sistólica/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Valor Preditivo dos Testes , Prognóstico , Taxa de Sobrevida/tendências , Fatores de Tempo , Estados Unidos/epidemiologia
11.
Am J Cardiol ; 116(11): 1724-30, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26443561

RESUMO

Cardiac output during right-sided heart catheterization is an important variable for patient selection of advanced therapies (cardiac transplantation and left ventricular assist device implantation). The Fick method to determine cardiac output is commonly used and typically uses estimated oxygen consumption (VO2) from 1 of 3 published empirical formulas. However, these estimation equations have not been validated in patients with heart failure and reduced ejection fraction (HFrEF). The objectives of the present study were to determine the accuracy of 3 equations for estimating VO2 compared with direct measurement of VO2 and determine the extent clinically significant error occurred in calculating cardiac output of patients with HFrEF. Breath-by-breath measurements of VO2 from 44 patients who underwent cardiac catheterization (66% men; age, 65 ± 11 years, left ventricular ejection fraction, 22 ± 6%) were compared with the derived estimations of LaFarge and Miettinen, Dehmer et al, and Bergstra et al. Single-sample t tests found only the mean difference between the estimation of LaFarge and Miettinen and the measured VO2 to be nonsignificant (-10.3 ml/min ± 6.2 SE, p = 0.053). Bland-Altman plots demonstrated unacceptably large limits of agreement for all equations. The rate of ≥25% error in the equations by LaFarge and Miettinen, Dehmer et al, and Bergstra et al occurred in 11%, 23%, and 45% of patients, respectively. Misclassification of cardiac index derived from each equation for 2 clinically important classifications: cardiogenic shock-21%, 23%, and 32% and hypoperfusion-16%, 16%, and 25%; respectively. In conclusion, these findings do not support the use of these empiric formulas to estimate the VO2 at rest in patients with HFrEF who underwent right-sided heart catheterization.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Consumo de Oxigênio , Adulto , Idoso , Idoso de 80 Anos ou mais , Cateterismo Cardíaco , Débito Cardíaco , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Volume Sistólico
13.
New Dir Youth Dev ; 2014(144): 17-30, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25537347

RESUMO

In contemporary developmental science, relational development systems models have been used to frame the positive youth development (PYD) perspective, which posits that youth will thrive when there is alignment between their strengths and ecological resources in their context. Evidence from the 4-H Study of PYD indicates that out-of-school-time youth development programs are key ecological resources enhancing youth thriving. This chapter discusses the particular facets of youth development programs (the "Big Three"-positive and sustained adult-youth relationships, skill-building activities, and youth leadership opportunities) involved in promoting youth thriving. The importance of using theory to design and implement programs is also discussed, and challenges of reaching the diversity of American youth with effective programs are noted.


Assuntos
Comportamento do Adolescente , Desenvolvimento do Adolescente , Desenvolvimento de Programas , Adolescente , Feminino , Objetivos , Humanos , Masculino , Modelos Psicológicos , Teoria de Sistemas
14.
Ear Nose Throat J ; 93(4-5): 168-73, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24817231

RESUMO

We conducted a retrospective study to reexamine the value of single-photon emission computed tomography (SPECT) in the evaluation of patients with neurotologic complaints, and to assess the intra- and inter-radiologist variability of SPECT readings. Our study population was made up of 63 patients--23 men and 40 women, aged 34 to 91 years (mean: 59)--who had presented to a tertiary care otolaryngology practice and university hospital for evaluation of head trauma, sensorineural hearing loss, tinnitus, and/or vertigo. All patients had undergone brain scanning with SPECT during their evaluation, and almost all had also undergone magnetic resonance imaging (MRI) and standard computed tomography (CT). We compared the findings of all three imaging modalities in terms of their ability to detect neurotologic abnormalities. We found that detection rates were very similar among the three modalities; abnormalities were found in 24% of SPECT scans, 26% of MRIs, and 23% of CTs. Nevertheless, we did find that among 60 patients who underwent all three types of imaging, 13 (22%) exhibited areas of cerebral hypoperfusion on SPECT while their MRIs and CTs were read as either normal or nonspecific. In all, 18 of these 60 patients (30%) exhibited normal or nonspecific findings on all three types of imaging. In addition, when SPECT scans were read by the same radiologist at different times, different results were reported for 17 of the 63 scans (27%). Likewise, when SPECT scans were read by different radiologists, different results were reported for 21 of 63 scans (33%). We conclude that SPECT may be a valuable complementary diagnostic modality for making a comprehensive neurotologic evaluation and that it may detect abnormalities in some patients whose other imaging is read as normal. However, we did not find that SPECT was the most sensitive of the three modalities in neurotologic evaluation, as we had previously found in a preliminary study that the senior author (R.T.S.) published in 1996. In addition, with respect to our radiologists, both their intra- and inter-reader reliability was low, and we recommend additional study on this matter.


Assuntos
Traumatismos Craniocerebrais/diagnóstico por imagem , Perda Auditiva Neurossensorial/diagnóstico por imagem , Zumbido/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Vertigem/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Circulação Cerebrovascular , Traumatismos Craniocerebrais/fisiopatologia , Feminino , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Radiologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Zumbido/fisiopatologia , Tomografia Computadorizada por Raios X , Vertigem/fisiopatologia
15.
J Youth Adolesc ; 43(6): 884-96, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24477498

RESUMO

School engagement is an important theoretical and practical cornerstone to the promotion of academic accomplishments. This article used a tripartite-behavioral, emotional, and cognitive-model of school engagement to assess the relationship between school engagement and academic success among high school students, and to determine whether a reciprocal relationship exists between these constructs. Data were derived from 710 youth (69% female) who took part in Waves 6 through 8 (Grades 10 through 12) of the 4-H study of positive youth development. Longitudinal confirmatory factor analyses confirmed the invariance of the tripartite model of school engagement. Results of a structural equation model showed that the components of school engagement and academic achievement were mutually predictive and that these predictions varied from grade to grade. Future possibilities for evaluating the relationship between school engagement and academic achievement, as well as the implications for educational policy and practice, are discussed.


Assuntos
Logro , Comportamento do Adolescente/psicologia , Desenvolvimento do Adolescente , Psicologia do Adolescente , Estudantes/psicologia , Adolescente , Análise Fatorial , Feminino , Inquéritos Epidemiológicos , Humanos , Estudos Longitudinais , Masculino , Modelos Psicológicos , Modelos Estatísticos , Instituições Acadêmicas , Estados Unidos
16.
Curr Heart Fail Rep ; 11(1): 111-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24445587

RESUMO

Heart failure (HF) is a growing health problem, at least in part due to the concurrent obesity epidemic plaguing developed countries. However, once a patient develops HF, an elevated BMI appears to confer a survival benefit--a phenomenon termed the "obesity paradox." The exact explanation for this paradox has been difficult to ascertain. Numerous plausible mechanisms have been asserted, including the fact that obese patients tend to be younger and more symptomatic, leading them to seek medical attention earlier in the course of their HF. Obese patients may also have larger energy reserves that help to offset the catabolic changes seen with HF. Other hypotheses highlight the limitations of BMI as an obesity classifier. The purpose of this review is to examine the various theories for the obesity paradox in HF and discuss the implications for the clinical management of obese patients with HF.


Assuntos
Insuficiência Cardíaca/complicações , Obesidade/complicações , Índice de Massa Corporal , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Humanos , Obesidade/mortalidade , Obesidade/fisiopatologia , Obesidade/terapia , Aptidão Física/fisiologia , Prognóstico , Redução de Peso
17.
Int J Cardiol ; 171(2): 265-9, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24387896

RESUMO

OBJECTIVES: To determine the utility of an artificial neural network (ANN) in predicting cardiovascular (CV) death in patients with heart failure (HF). BACKGROUND: ANNs use weighted inputs in multiple layers of mathematical connections in order to predict outcomes from multiple risk markers. This approach has not been applied in the context of cardiopulmonary exercise testing (CPX) to predict risk in patients with HF. METHODS: 2635 patients with HF underwent CPX and were followed for a mean of 29 ± 30 months. The sample was divided randomly into ANN training and testing sets to predict CV mortality. Peak VO2, VE/VCO2 slope, heart rate recovery, oxygen uptake efficiency slope, and end-tidal CO2 pressure were included in the model. The predictive accuracy of the ANN was compared to logistic regression (LR) and a Cox proportional hazards (PH) score. A multi-layer feed-forward ANN was used and was tested with a single hidden layer containing a varying number of hidden neurons. RESULTS: There were 291 CV deaths during the follow-up. An abnormal VE/VCO2 slope was the strongest predictor of CV mortality using conventional PH analysis (hazard ratio 3.04; 95% CI 2.2-4.2, p<0.001). After training, the ANN was more accurate in predicting CV mortality compared to LR and PH; ROC areas for the ANN, LR, and PH models were 0.72, 0.70, and 0.69, respectively. Age and BMI-adjusted odds ratios were 4.2, 2.6, and 2.9, for ANN, LR, and PH, respectively. CONCLUSION: An ANN model slightly improves upon conventional methods for estimating CV mortality risk using established CPX responses.


Assuntos
Teste de Esforço , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Redes Neurais de Computação , Adulto , Idoso , Feminino , Seguimentos , Insuficiência Cardíaca/fisiopatologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Estudos Retrospectivos , Medição de Risco/métodos
19.
Mayo Clin Proc ; 88(3): 251-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23489451

RESUMO

OBJECTIVE: To determine the impact of cardiorespiratory fitness (FIT) on survival in relation to the obesity paradox in patients with systolic heart failure (HF). PATIENTS AND METHODS: We studied 2066 patients with systolic HF (body mass index [BMI] ≥18.5 kg/m(2)) between April 1, 1993 and May 11, 2011 (with 1784 [86%] tested after January 31, 2000) from a multicenter cardiopulmonary exercise testing database who were followed for up to 5 years (mean ± SD, 25.0±17.5 months) to determine the impact of FIT (peak oxygen consumption <14 vs ≥14 mL O2 ∙ kg(-1) ∙ min(-1)) on the obesity paradox. RESULTS: There were 212 deaths during follow-up (annual mortality, 4.5%). In patients with low FIT, annual mortality was 8.2% compared with 2.8% in those with high FIT (P<.001). After adjusting for age and sex, BMI was a significant predictor of survival in the low FIT subgroup when expressed as a continuous (P=.03) and dichotomous (<25.0 vs ≥25.0 kg/m(2)) (P=.01) variable. Continuous and dichotomous BMI expressions were not significant predictors of survival in the overall and high FIT groups after adjusting for age and sex. In patients with low FIT, progressively worse survival was noted with BMI of 30.0 or greater, 25.0 to 29.9, and 18.5 to 24.9 (log-rank, 11.7; P=.003), whereas there was no obesity paradox noted in those with high FIT (log-rank, 1.72; P=.42). CONCLUSION: These results indicate that FIT modifies the relationship between BMI and survival. Thus, assessing the obesity paradox in systolic HF may be misleading unless FIT is considered.


Assuntos
Insuficiência Cardíaca Sistólica/mortalidade , Obesidade/complicações , Aptidão Física , Adulto , Idoso , Índice de Massa Corporal , Bases de Dados Factuais , Teste de Esforço , Feminino , Seguimentos , Insuficiência Cardíaca Sistólica/complicações , Insuficiência Cardíaca Sistólica/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Obesidade/mortalidade , Obesidade/fisiopatologia , Consumo de Oxigênio , Modelos de Riscos Proporcionais
20.
Int J Cardiol ; 168(2): 1496-501, 2013 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-23391698

RESUMO

BACKGROUND: Heart rate recovery (HRR) has been observed to be a significant prognostic measure in patients with heart failure (HF). However, the prognostic value of HRR has not been examined in regard to the level of patient effort during exercise testing. Using the peak respiratory exchange ratio (RER) and a large multicenter HF database we examined the prognostic utility of HRR. METHODS: Cardiopulmonary exercise testing (CPX) was performed in 806 HF patients who then underwent an active cool-down of at least 1 min. Peak oxygen consumption (VO2), ventilatory efficiency (VE/VCO2 slope), and peak RER were determined with subjects categorized into subgroups according to peak RER (<1.00, 1.00-1.09, ≥ 1.10). HRR was defined as the difference between heart rate at peak exercise and 1 min following test termination. Patients were followed for major cardiac events for up to four years post-CPX. RESULTS: There were 163 major cardiac events (115 deaths, 20 left ventricular assist device implantations, and 28 transplantations) during the four year tracking period. Univariate Cox regression analysis results identified HRR as a significant (p<0.05) univariate predictor of adverse events regardless of the RER achieved. Multivariate Cox regression analysis in the overall group revealed that the VE/VCO2 slope was the strongest predictor of adverse events (chi-square: 110.9, p<0.001) with both HRR (residual chi-square: 16.7, p<0.001) and peak VO2 (residual chi-square: 10.4, p<0.01) adding significant prognostic value. CONCLUSIONS: HRR after symptom-limited exercise testing performed at sub-maximal efforts using RER to categorize level of effort is as predictive as HRR after maximal effort in HF patients.


Assuntos
Teste de Esforço/métodos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca/fisiologia , Recuperação de Função Fisiológica/fisiologia , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Insuficiência Cardíaca/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
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