334 research outputs found

    Relation of a Maximal Exercise Test to Change in Exercise Tolerance During Cardiac Rehabilitation

    Get PDF
    The purpose of this study was to test the hypothesis that an individualized exercise training target heart rate (HR) based on a maximal graded exercise test (GXT) is associated with greater improvements in exercise tolerance during cardiac rehabilitation (CR) compared with no GXT. In this retrospective study, we identified patients who completed 9 to 36 visits of CR between 2001 and 2016, with a length of stay ≤18 weeks and a visit frequency of 1 to 3 days per week. Patients were grouped based on whether their exercise was guided by a target HR determined from a GXT. To assess the relation between GXT and change in exercise training metabolic equivalents of task (METs), we used generalized linear models adjusted for age, gender, race, referral reason, CR visits, CR frequency, METs at start, CR location, and year of participation. Out of 4,455 patients (37% female, 48% White, median age = 62 years), 53% were prescribed a target HR based on a GXT. Compared with no GXT, a GXT was associated with a significantly greater increase in covariate-adjusted METs during CR and percentage change from start (+0.44 METs [95% confidence interval [CI] 0.38 to 0.51] and +17% [95% CI 14% to 19%], respectively). In a sensitivity analysis limited to patients with 24 to 36 visits at ≥2 days per week (n = 1,319), a GXT was associated with a significantly greater increase in covariate-adjusted exercise training METs (+0.51 [95% CI 0.36 to 0.66]; +19% [95% CI 13% to 24%]). In conclusion, to maximize the potential increase in exercise capacity during CR, patients should undergo a GXT to determine an individualized exercise training target HR

    Predicting diabetes mellitus using SMOTE and ensemble machine learning approach: The Henry Ford ExercIse Testing (FIT) project

    Get PDF
    Machine learning is becoming a popular and important approach in the field of medical research. In this study, we investigate the relative performance of various machine learning methods such as Decision Tree, Naïve Bayes, Logistic Regression, Logistic Model Tree and Random Forests for predicting incident diabetes using medical records of cardiorespiratory fitness. In addition, we apply different techniques to uncover potential predictors of diabetes. This FIT project study used data of 32,555 patients who are free of any known coronary artery disease or heart failure who underwent clinician-referred exercise treadmill stress testing at Henry Ford Health Systems between 1991 and 2009 and had a complete 5-year follow-up. At the completion of the fifth year, 5,099 of those patients have developed diabetes. The dataset contained 62 attributes classified into four categories: demographic characteristics, disease history, medication use history, and stress test vital signs. We developed an Ensembling-based predictive model using 13 attributes that were selected based on their clinical importance, Multiple Linear Regression, and Information Gain Ranking methods. The negative effect of the imbalance class of the constructed model was handled by Synthetic Minority Oversampling Technique (SMOTE). The overall performance of the predictive model classifier was improved by the Ensemble machine learning approach using the Vote method with three Decision Trees (Naïve Bayes Tree, Random Forest, and Logistic Model Tree) and achieved high accuracy of prediction (AUC = 0.92). The study shows the potential of ensembling and SMOTE approaches for predicting incident diabetes using cardiorespiratory fitness data

    Chronotropic incompetence and long-term risk of heart failure: The henry ford exercise testing project

    Get PDF
    Background: Chronotropic incompetence (CI) has been associated with cardiovascular mortality. However, its relationship with long-term risk of heart failure (HF) is not well studied. Methods: We included 43,098 participants (mean age 51.7±12.3 years, 47.5% females, 66.6% white) of the FIT project who completed a clinically indicated exercise test between 1991 and 2009. Patients with coronary artery disease, prior HF or on heart rate reducing medications were excluded. Incident HF was defined by having a documented diagnosis in 3 separate clinical encounters. CI was defined by inability to achieve 85% of maximal age predicted heart rate (calculated by 220 - age) with exercise. Multivariable adjusted Cox models were used to assess the independent association of CI with incident HF. Results: At baseline, 5,249 (12.2%) had CI. After a mean follow-up duration of 10.9 ± 4.6 years, 1329 (3.2%) experienced new onset HF. The cumulative incidence of HF was 397 (7.6%) among CI patients compared with 992 (2.6%) among chronotropic competent patients. Figure 1 shows the cumulative incidence of heart failure by CI status. In multivariable Cox regression models, CI was associated with increased risk of incident heart failure (HR 1.73; 95% CI 1.48 – 2.03, p \u3c0.001) after adjusting for confounders. There were no interactions by age, sex, race, body mass index. Conclusions: Our study shows that CI is an independent risk factor for HF. Further research is needed to determine whether CI could be a therapeutic target for HF

    Social Cognitive Outcomes are Associated With Improvements in Mobility Performance Following Lifestyle Intervention in Prostate Cancer Patients Undergoing Androgen Deprivation Therapy

    Get PDF
    Objective To compare the effects of an exercise and dietary intervention with those of standard-of-care management upon change in lift and carry performance and mobility-related self-efficacy beliefs and explore associations in prostate cancer patients undergoing androgen deprivation therapy. Methods 32 prostate cancer patients (M age = 66.2 years; SD = 7.8) undergoing androgen deprivation therapy were randomly assigned to a 3-month exercise and dietary lifestyle intervention (n = 16) or standard-of-care management (n = 16). Outcome assessments were obtained at baseline, 2- and 3-month follow-up. Results The lifestyle intervention resulted in significantly greater improvements in lift and carry performance (p = 0.01) at 2 Months (d = 1.01; p \u3c 0.01) and 3 Months (d = 0.95; p \u3c 0.01) and superior improvements in mobility-related self-efficacy at 2 Months (d = 0.38) and 3 Months (d = 0.58) relative to standard-of-care. Mobility-related self-efficacy (r = -.66; p = 0.006) and satisfaction with function (r = -.63; p = 0.01) were significantly correlated with lift and carry performance at 3 Months. Conclusions The exercise and dietary lifestyle intervention yielded superior improvements in lift and carry performance and mobility-related self-efficacy relative to standard-of-care and key social cognitive outcomes were associated with more favorable mobility performance

    Tracking Cardiac Rehabilitation Utilization in Medicare Beneficiaries: 2017 UPDATE

    Get PDF
    PURPOSE: This study updates cardiac rehabilitation (CR) utilization data in a cohort of Medicare beneficiaries hospitalized for CR-eligible events in 2017, including stratification by select patient demographics and state of residence. METHODS: We identified Medicare fee-for-service beneficiaries who experienced a CR-eligible event and assessed their CR participation (≥1 CR sessions in 365 d), engagement, and completion (≥36 sessions) rates through September 7, 2019. Measures were assessed overall, by beneficiary characteristics and state of residence, and by primary (myocardial infarction; coronary artery bypass surgery; heart valve repair/replacement; percutaneous coronary intervention; or heart/heart-lung transplant) and secondary (angina; heart failure) qualifying event type. RESULTS: In 2017, 412 080 Medicare beneficiaries had a primary CR-eligible event and 28.6% completed ≥1 session of CR within 365 d after discharge from a qualifying event. Among beneficiaries who completed ≥1 CR session, the mean total number of sessions was 25 ± 12 and 27.6% completed ≥36 sessions. Nebraska had the highest enrollment rate (56.1%), with four other states also achieving an enrollment rate \u3e50% and 23 states falling below the overall rate for the United States. CONCLUSIONS: The absolute enrollment, engagement, and program completion rates remain low among Medicare beneficiaries, indicating that many patients did not benefit or fully benefit from a class I guideline-recommended therapy. Additional research and continued widespread adoption of successful enrollment and engagement initiatives are needed, especially among identified populations

    Effects of a group-mediated cognitive behavioral lifestyle intervention on select social cognitive outcomes in prostate cancer patients undergoing androgen deprivation therapy

    Get PDF
    Objective. To compare the effects of a group-mediated cognitive behavioral (GMCB) exercise and dietary (EX+D) intervention with those of standard-of-care (SC) treatment on select social cognitive outcomes in prostate cancer (PCa) patients undergoing androgen deprivation therapy (ADT). Methods. In the single-blind, 2-arm, randomized controlled Individualized Diet and Exercise Adherence–Pilot (IDEA-P) trial, 32 PCa patients (mean age = 66.2 years; SD = 7.8) undergoing ADT were randomly assigned to a 12-week EX+D intervention (n = 16) or SC treatment (n = 16). The exercise component of the personalized EX+D intervention integrated a combination of supervised resistance and aerobic exercise performed twice per week. The dietary component involved counseling and education to modify dietary intake and composition. Blinded assessments of social cognitive outcomes were obtained at baseline and 2-month and 3-month follow-up. Results. Intent-to-treat analysis of covariance demonstrated that the EX+D intervention resulted in significantly greater improvements in scheduling (P \u3c .05), coping (P \u3c .01), and exercise self-efficacy (P \u3c .05), and satisfaction with function (P \u3c .01) at 3 months relative to SC. Results of partial correlation analysis also demonstrated that select social cognitive outcomes were significantly correlated with primary trial outcomes of mobility performance and exercise participation (P \u3c .05) at 3-month follow-up. Conclusions: The GMCB lifestyle intervention yielded more favorable improvements in relevant social cognitive outcomes relative to SC among PCa patients undergoing ADT. Additionally, more favorable social cognitive outcomes were associated with superior mobility performance and exercise participation following the independent maintenance phase of the EX+D intervention

    CODE-2 : moored array and large-scale data report

    Get PDF
    The Coastal Ocean Dynamics Experiment (CODE) was undertaken to identify and study the important dynamical processes which govern the wind-driven motion of coastal water over the continental shelf. The initial effort in this multi-year, multi-institutional research program was to obtain high-quality data sets of all the relevant physical variables needed to construct accurate kinematic and dynamic descriptions of the response of shelf water to strong wind forcing in the 2 to 10 day band. A series of two small-scale, densely- instrumented field experiments of approximately four months duration (called CODE-1 and CODE-2) were designed to explore and to determine the kinematics and momentum and heat balances of the local wind-driven flow over a region of the northern California shelf which is characterized by both relatively simple bottom topography and large wind stress events in both winter and summer. A more lightly instrumented, long -term, large-scale component was designed to help separate the local wind-driven response in the region of the small-scale experiments from motions generated either offshore by the California Current system or in some distant region along the coast, and also to help determine the seasonal cycles of the atmospheric forcing, water structure, and coastal currents over the northern California shelf. The first small-scale experiment (CODE-1) was conducted between April and August, 1981 as a pilot study in "which primary emphasis was placed on characterizing the wind-driven "signal" and the "noise" from which this signal must be extracted. In particular, CODE-1 was designed to identify the key features of the circulation and its variability over the northern California shelf and to determine the important time and length scales of the wind-driven response. The second small-scale experiment (CODE-2) was conducted between April and August, 1982 and was designed to sample more carefully the mesoscale horizonta1 variability observed in CODE-1. This report presents a basic description of the moored array data and some other Eulerian data collected during CODE-2. A brief description of the CODE-2 field program is presented first, followed by a description of the common data analysis procedures used to produce the various data sets presented here. Then basic descriptions of the following data sets are presented: (a) the coastal and moored meteorological measurements, (b) the moored current measurements, (c) array plots of the surface wind stress and near-surface current measurements, (d) the moored temperature and conductivity observations, (e) the bottom pressure measurements, and (f) the wind and adjusted coastal sea level observations obtained as part of the CODE-2 large-scale component.This work has been supported by the National Science Foundation

    Unnatural Amino Acid Incorporation into Virus-Like Particles

    Get PDF
    Virus-like particles composed of hepatitis B virus (HBV) or bacteriophage Qβ capsid proteins have been labeled with azide- or alkyne-containing unnatural amino acids by expression in a methionine auxotrophic strain of E. coli. The substitution does not affect the ability of the particles to self-assemble into icosahedral structures indistinguishable from native forms. The azide and alkyne groups were addressed by Cu(I)-catalyzed [3 + 2] cycloaddition: HBV particles were decomposed by the formation of more than 120 triazole linkages per capsid in a location-dependent manner, whereas Qβ suffered no such instability. The marriage of these well-known techniques of sense-codon reassignment and bioorthogonal chemical coupling provides the capability to construct polyvalent particles displaying a wide variety of functional groups with near-perfect control of spacing
    • …
    corecore