JEFFERSON LUIS VIEIRA
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina - Médico
3 resultados
Resultados de Busca
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conferenceObject Effects of Reducing Exposure to Air Pollution With a Filter on Exercise: A Randomized, Prospective, Double-Blind, Controlled Study of Heart Failure(2015) VIEIRA, Jefferson L.; GUIMARAES, Guilherme V.; ANDRE, Paulo A. de; SALDIVA, Paulo H.; BOCCHI, Edimar A.- Effects of reducing exposure to air pollution on submaximal cardiopulmonary test in patients with heart failure: Analysis of the randomized, double-blind and controlled FILTER-HF trial(2016) VIEIRA, Jefferson L.; GUIMARAES, Guilherme V.; ANDRE, Paulo A. de; SALDIVA, Paulo H. Nascimento; BOCCHI, Edimar A.Background: Air pollution exposure could mitigate the health benefits of exercise in patients with heart failure (HF). We tested the effects of a respiratory filter on HF patients exposed to air pollution during exercise. Methods and Results: Ancillary analysis of the FILTER-HF trial, focused on the exercise outcomes. In a randomized, double-blind, 3-way crossover design, 26 HF patients and 15 control volunteers were exposed to clean air, unfiltered dilute diesel engine exhaust (DE), or filtered DE for 6 min during a submaximal cardiopulmonary testing in a controlled-exposure facility. Prospectively collected data included six-minute walking test [6mwt], VO2, VE/VCO2 Slope, O(2)Pulse, pulmonary ventilation [VE], tidal volume, VD/Vt, oxyhemoglobin saturation and CO2-rebreathing. Compared to clean air, DE adversely affected VO2 (11.0 +/- 3.9 vs. 8.4 +/- 2.8 ml/kg/min; p < 0.001); 6mwt (243.3 +/- 13.0 vs. 220.8 +/- 13.7 m; p = 0.030); and O(2)Pulse (8.9 +/- 1.0 vs. 7.8 +/- 0.7 ml/beat; p < 0.001) in HF patients. Compared to DE, filtration reduced the particulate concentration from 325 +/- 31 to 25 +/- 6 mu g/m(3), and was associated with an increase in VO2 (10.4 +/- 3.8 ml/kg/min; p < 0.001 vs. DE) and O(2)Pulse (9.7 +/- 1.1 ml/beat; p < 0.001 vs. DE) in patients with HF. Filtration was associated with higher VE and CO2-rebreathing in both groups. VE/VCO2 Slope was higher among patients with HF. Conclusion: DE adversely affects exercise capacity in patients with HF. A simple respiratory filter can reduce the adverse effects of pollution on VO2 and O(2)Pulse. Given the worldwide prevalence of exposure to traffic-related air pollution, these findings are relevant for public health especially in this highly susceptible population. The filter intervention holds great promise that needs to be tested in future studies.
- Systemic effects of controlled exposure to diesel exhaust: a meta-analysis from randomized controlled trials(2017) VIEIRA, Jefferson Luis; MACEDO, Francisco Yuri; BENJO, Alexandre Miguel; GUIMARAES, Guilherme V.; CONTRERAS, Johanna Paola; BOCCHI, Edimar A.Introduction: Ambient air pollution is associated with adverse cardiovascular events. This meta-analysis aimed to investigate the short-term association between air pollution and cardiovascular effects on healthy volunteers. Methods: We searched databases to identify randomized trials with controlled human exposures to either of two models for studying ambient particulate matter: diesel-exhaust or concentrated ambient particles. Estimates of size effect were performed using standardized mean difference (SMD). Heterogeneity was assessed with I-2 statistics. Outcomes were vascular function estimated by forearm blood flow (FBF), blood pressure, heart rate, and blood analysis. Results: Database searches yielded 17 articles (n=342) with sufficient information for meta-analyses. High levels of heterogeneity for the some outcomes were analyzed using random-effects model. The pooled effect estimate showed that short-term exposure to air pollution impaired FBF response from 2.7 to 2.5mL/100mL tissue/min (SMD 0.404; p=.006). There was an increase in 5000 platelet/mm(3) following pollution exposure (SMD 0.390; p=.050) but no significant differences for other outcomes. Conclusion: Controlled human exposures to air pollution are associated with the surrogates of vascular dysfunction and increase in platelet count, which might be related to adverse cardiovascular events. Given the worldwide prevalence of exposure to air pollution, these findings are relevant for public health.