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BACKGROUND: Exercise training is an effective and low-cost tool for COPD rehabilitation. Thus, validating a non-exhaustive method to determine a patient's anaerobic threshold would be a very interesting tool in practical settings. We aimed to test the reproducibility of critical velocity values determined in a non-exhaustive manner (CVNE) and tolerance for exercise performed at this physiological marker in subjects with COPD. METHODS: Twelve subjects with COPD were evaluated in this cross-sectional study. The study was divided into 2 phases: Phase A consisted of reproducibility of CVNE for subjects with COPD, and Phase B determined the tolerance for exercise tests performed at this physiological marker. RESULTS: The proposed protocol for determining CVNE presented fair reproducibility according to blood lactate concentrations (intraclass correlation coefficient = 0.58). However, we cannot consider that the tests were reproducible due to the wide CI (0.03-0.85). Furthermore, moderate and strong correlations were observed between the CVNE determined by lactate concentration, by oxygen consumption (...) (r = 0.66), and by heart rate (r = 0.88). However, a high limit of agreement was observed ±1.45 km/h and ±1.55 km/h, respectively. In the tolerance for exercise test, none of the subjects presented lactate destabilization, whereas 3 tests were interrupted by oxygen saturation decline and 1 test was interrupted by hemodynamic instability. CONCLUSIONS: Although most of the subjects presented good tolerance for exercise at CVNE, fair levels of reproducibility were observed in subjects with COPD, even using lactate. Thus, the use of CVNE determined through double 3-min efforts should be considered with caution. [ABSTRACT FROM AUTHOR]

BACKGROUND: Mucociliary clearance is the main defense mechanism of the respiratory system, and it is influenced by several stimuli, including aerobic exercise and cigarette smoking. We evaluated the acute response of mucociliary clearance to aerobic exercise in smokers and nonsmokers compared with that found after acute smoking and smoking combined with exercise. Also, we investigated whether there was a correlation between mucociliary clearance and the autonomic nervous system under these conditions. METHODS: Twenty-one smokers were evaluated for mucociliary clearance by saccharin transit time (STT), and the response of the autonomic nervous system was evaluated by heart rate variability after aerobic exercise, after exercise followed by smoking, after acute smoking, and after rest. For comparison, 17 nonsmokers were also assessed during exercise. Repeated-measures analysis of variance with the Tukey test or the Friedman test followed by the Dunn test was used to evaluate the STT, autonomic response, and other variables to exercise and/or smoking in smokers. A paired t test or Wilcoxon test was used to analyze responses to exercise in nonsmokers. Correlations were evaluated using Pearson or Spearman coefficients. RESULTS: The STT was reduced after exercise in both groups, with similar responses between them. Other stimuli also reduced the STT. The STT showed a negative correlation with sympathetic activity in smokers and a positive correlation with the parasympathetic system in nonsmokers. CONCLUSIONS: Although impaired in smokers, mucociliary clearance responded to the stimulus of exercise, as demonstrated by similar STTs compared with nonsmokers. This response was correlated with the autonomic nervous system in both groups. In smokers, mucociliary clearance also responded to the stimuli of smoking and exercise followed by smoking. [ABSTRACT FROM AUTHOR]

BACKGROUND: Exposure to cigarette smoke causes significant impairment in mucociliary clearance (MCC), which predisposes patients to secretion retention and recurrent airway infections that play a role in exacerbations of COPD. To determine whether smoking cessation may influence MCC and frequency of exacerbations, the following groups were evaluated: ex-smokers with COPD, smokers with COPD, current smokers with normal lung function, and nonsmokers with normal lung function. METHODS: Ninety-three subjects were divided into 4 groups: ex-smokers with COPD (n = 23, 62.4 ± 8.0 y, 13 males), smokers with COPD (n = 17, 58.2 ± 8.0 y, 6 males), current smokers (n = 27, 61.5 ± 6.4 y, 17 males), and nonsmokers (n = 26, 60.8 ± 11.3 y, 7 males). MCC was evaluated using the saccharin transit time (STT) test, and the frequency of exacerbations in the last year was assessed by questionnaire. The Kruskal-Wallis test followed by Dunn’s test were used to compare STT among groups, and the Goodman test was used to compare the frequency of exacerbations. RESULTS: STT of smokers with COPD (16.5 [11–28] min; median [interquartile range 25–75%]) and current smokers (15.9 [10 –27] min) was longer compared with ex-smokers with COPD (9.7 [6 –12] min) and nonsmokers (8 [6 –16] min) (P < .001). There was no difference in STT values between smokers with COPD and current smokers, and these values in ex-smokers with COPD were similar to the control group (P > .05). The frequency of exacerbations was lower in ex-smokers with COPD compared with smokers with COPD. CONCLUSIONS: One year after smoking cessation, subjects with COPD had improved mucociliary clearance. [ABSTRACT FROM AUTHOR]

Background: There are still gaps in the knowledge regarding the damage to mucociliary and autonomous systems from passive exposure to cigarette smoke. Also, the influence of the frequency and duration of exposure on these systems is still unclear. The objective of this work was to verify the effects of passive smoking on mucociliary clearance and adult autonomic nervous systems and investigate the influence of frequency and time of passive exposure on these systems., Methods: 44 smokers (smoking group), 38 passive smokers (passive smoking group), and 38 healthy individuals (control group) were evaluated. Evaluation of lung function was performed. To analyze the autonomic nervous system, heart rate variability data were collected. Hemodynamic parameters were collected. Mucociliary clearance was evaluated using the saccharin transit time test., Results: The passive smoking group presented reduced lung function (P = .02). Systolic blood pressure was significantly greater in the passive smoking group when compared with the smoking group (P = .02). The passive smoking group presented significantly slower transportability time than the control group. No differences were observed between the groups for the heart rate variability data. There was a significant correlation (P < .05) between the frequency of exposure and diastolic blood pressure, oxygen saturation, and FEF(25-75%). Correlation analyses also demonstrated a reduction of global autonomic activity according to exposure load, in addition to a reduction in vagal activity and an increase in sympathetic activity according to exposure frequency., Conclusions: Passive smokers presented worse mucociliary clearance, and there was a correlation between passive exposure load and damage to the hemodynamic response, pulmonary function and autonomic nervous system., (Copyright © 2016 by Daedalus Enterprises.)