Neuromuscular electrical stimulation improves exercise tolerance in chronic obstructive pulmonary disease patients with better preserved fat-free mass

BACKGROUND: High-frequency neuromuscular electrical stimulation increases exercise tolerance in patients with advanced chronic obstructive pulmonary disease (COPD patients). However, it is conceivable that its benefits are more prominent in patients with better-preserved peripheral muscle function and structure. OBJECTIVE: To investigate the effects of high-frequency neuromuscular electrical stimulation in COPD patients with better-preserved peripheral muscle function. Design: Prospective and cross-over study. METHODS: Thirty COPD patients were randomly assigned to either home-based, high-frequency neuromuscular electrical stimulation or sham stimulation for six weeks. The training intensity was adjusted according to each subject's tolerance. Fat-free mass, isometric strength, six-minute walking distance and time to exercise intolerance (Tlim) were assessed. RESULTS: Thirteen (46.4%) patients responded to high-frequency neuromuscular electrical stimulation; that is, they had a post/pre &#916; Tlim >10% after stimulation (unimproved after sham stimulation). Responders had a higher baseline fat-free mass and six-minute walking distance than their seventeen (53.6%) non-responding counterparts. Responders trained at higher stimulation intensities; their mean amplitude of stimulation during training was significantly related to their fat-free mass (r = 0.65; p<0.01). Logistic regression revealed that fat-free mass was the single independent predictor of Tlim improvement (odds ratio [95% CI] = 1.15 [1.04-1.26]; p<0.05). CONCLUSIONS: We conclude that high-frequency neuromuscular electrical stimulation improved the exercise capacity of COPD patients with better-preserved fat-free mass because they tolerated higher training stimulus levels. These data suggest that early training with high-frequency neuromuscular electrical stimulation before tissue wasting begins might enhance exercise tolerance in patients with less advanced COPD

Tinnitus and Neuropsychological Dysfunction in the Elderly: A Systematic Review on Possible Links

Introduction: Tinnitus is a common and disabling symptom often associated with hearing loss. While clinical practice frequently shows that a certain degree of psychological discomfort often characterizes tinnitus suffers, it has been recently suggested in adults as a determining factor for cognitive decline affecting attention and memory domains. The aim of our systematic review was to provide evidence for a link between tinnitus, psychological distress, and cognitive dysfunction in older patients and to focus on putative mechanisms of this relationship. Methods: We performed a systematic review, finally including 192 articles that were screened. This resulted in 12 manuscripts of which the full texts were included in a qualitative analysis. Results: The association between tinnitus and psychological distress, mainly depression, has been demonstrated in older patients, although only few studies addressed the aged population. Limited studies on cognitive dysfunction in aged patients affected by chronic tinnitus are hardly comparable, as they use different methods to validate cognitive impairment. Actual evidence does not allow us with certainty to establish if tinnitus matters as an independent risk factor for cognitive impairment or evolution to dementia. Conclusion: Tinnitus, which is usually associated with age-related hearing loss, might negatively affect emotional wellbeing and cognitive capacities in older people, but further studies are required to improve the evidence

A symptom-limited incremental step test determines maximum physiological responses in patients with chronic obstructive pulmonary disease

Background: Step tests have been used to evaluate exercise tolerance and effort-related hypoxemia in different diseases. A symptom-limited incremental step test (IST) has never been tested in COPD patients.Aim: To compare maximal physiological responses between an IST and cardiopulmonary exercise testing (CPET), to test the reproducibility of the IST on different days, and to provide a predict equation to estimate VO2 from the IST in patients with COPD.Material and methods: At the same day, thirty-four patients (VEF1 46 +/- 14% of pred) underwent a CPET on cycle ergometer and the first 151 (IST-1) (1 h apart). After 2-5 days, patients repeated the IST (IST-2). Pulmonary gas exchange was measured during all tests.Results: Peak VO2 was significantly higher in IST-1 and IST-2 than in CEPT (Mean +/- SD: 1.19 +/- 0.39 L, 1.20 +/- 0.40 L, 1.07 +/- 0.35 L) with no difference for ventilation (VE), heart rate (HR), and perception of effort. ISTs were highly reproducible, with significant intraclass correlation coefficient (CCI [95% confidence interval]) for number of steps (0.98[0.95-0.99]), VO2 (0.99 [0.98-0.99]), VE (0.97[0.93-0.99]), HR (0.92[0.81-0.97]), and SpO(2) (0.96[0.90-0.98]). Desaturation was significantly higher for IST-1 and IST-2 compared with cycling (Mean +/- SD: -6 +/- 5%, -6 +/- 4%, - 3 +/- 3%). Number of steps and patient weight explained 81% of the variance in peak VO2 (p < 0.001).Conclusion: A symptom-limited incremental step test, externally paced, elicits maximal cardiopulmonary and metabolic responses, and is well tolerated and reproducible in patients with COPD. (C) 2013 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Univ Nove Julho UNINOVE, Postgrad Program Rehabil Sci, BR-01504001 São Paulo, BrazilFed Univ São Paulo UNIFESP, Dept Med, Div Resp Dis, São Paulo, BrazilUniv Fed Juiz de Fora, Human Physiol Dept, Juiz de Fora, MG, BrazilFed Univ São Paulo UNIFESP, Dept Med, Div Resp Dis, São Paulo, BrazilFAPESP: 2010/09732-6Web of Scienc

The pattern and timing of breathing during incremental exercise: a normative study

Clinical evaluation of the pattern and timing of breathing during submaximal exercise can be valuable for the identification of the mechanical ventilatory consequences of different disease processes and for assessing the efficacy of certain interventions.Sedentary individuals (60 male/60 female, aged 20-80 yrs) were randomly selected from >8,000 subjects and submitted to ramp incremental cycle ergometry. Tidal volume (V-T)/ resting inspiratory capacity, respiratory frequency, total respiratory time (Trot), inspiratory time (T-I), expiratory time (T-E), duty cycle (TI/Ttot) and mean inspiratory flow (V-T/T-I) were analysed at selected submaximal ventilatory intensities.Senescence and female sex were associated with a more tachypnoeic breathing pattern during isoventilation. the decline in T-tot was proportional to the TI and TE P reductions, i.e. T-I/T-tot was remarkably constant across age strata, independent of sex. the pattern, but not timing, of breathing was also influenced by weight and height; a set of demographically and anthropometrically based prediction equations are therefore presented.These data provide a frame of reference for assessing the normality of some clinically useful indices of the pattern and timing of breathing during incremental cycle ergometry in sedentary males and females aged 20-80 yrs.Universidade Federal de São Paulo, Pulmonary Funct & Clin Exercise Physiol Unit, Div Resp, Dept Med,Paulista Sch Med, BR-04020050 São Paulo, BrazilUniv Glasgow, Ctr Exercise Sci & Med, Inst Biol & Life Sci, Glasgow, Lanark, ScotlandUniversidade Federal de São Paulo, Pulmonary Funct & Clin Exercise Physiol Unit, Div Resp, Dept Med,Paulista Sch Med, BR-04020050 São Paulo, BrazilWeb of Scienc

A step test to assess exercise-related oxygen desaturation in interstitial lung disease

A 6-min step test (6MST) may constitute a practical method for routinely assessing effort tolerance and exercise-related oxyhaemoglobin desaturation (ERD) in the primary care of patients with interstitial lung disease.In total, 31 patients (19 males) with idiopathic pulmonary fibrosis I and chronic hypersensitivity pneumonia were submitted, on different days, to two 6MSTs. Physiological responses were compared with those found on maximal and submaximal cycle ergometer tests at the same oxygen uptake I Chronic breathlessness was also determined, as measured by the baseline dyspnoea index (BDI).Responses to 6MST were highly reproducible: 1.3 +/- 2.0 steps(.)min(-1), +/- 5 beats(.)min(-1) (cardiac frequency), +/- 50 mL(.)min(-1) (V'O-2), +/- 7 L(.)min(-1) (minute ventilation) and +/- 2% (arterial oxygen saturation measured by pulse oximetry (Sp,O-2)). the number of steps climbed in 6 min was correlated to peak V'O-2 and the BDI. There were significant associations among the tests in relation to presence (change in Sp,O-2 between rest and exercise >= 4%) and severity (Sp,O-2 < 88%) of ERD. Four patients, however, presented ERD only in response to 6MST. Resting diffusing capacity of the lung for carbon monoxide and alveolar-arterial oxygen tension difference were the independent predictors of the number of steps climbed.A single-stage, self-paced 6-min step test provided reliable and reproducible estimates of exercise capacity and exercise-related oxyhaemoglobin desaturation in interstitial lung disease patients.UNIFESP, EPM, Dept Med,SEFICE, Div Resp,Pulm Funct & Clin Exercise Physiol Unit, BR-04020050 São Paulo, BrazilUNIFESP, EPM, Dept Med,SEFICE, Div Resp,Pulm Funct & Clin Exercise Physiol Unit, BR-04020050 São Paulo, BrazilWeb of Scienc

Expression of matrix metalloproteinases -2 and -9 in saliva from patients with chronic obstructive pulmonary disease

The increased expression of matrix metalloproteinases (MMP) is considered a key factor in the development of chronic obstructive pulmonary disease (COPD). This study aimed at assessing expression levels of MMP-2 and MMP-9 in saliva from patients with COPD, comparing them to those of healthy subjects, thus assessing the feasibility of characterizing specific biomarkers for COPD. Patients with COPD (n=16) and healthy controls (n=9) were selected; both groups submitted to spirometry and to collection of saliva samples. Saliva levels of MMP-2 and MMP-9 were determined by Western blot. MMP-2 and MMP-9 levels were significantly higher in COPD patients than in control subjects. In COPD patients, a moderate, negative correlation was found between MMP-2 concentration and forced expiatory volume at the first second (r= -0.582; p=0.014). These findings open new perspectives to study specific biomarkers in saliva to predict and monitor airway obstruction in COPD patients.O aumento da expressão das metaloproteinases da matriz extracelular (MPM) é considerado um importante fator no desenvolvimento da doença pulmonar obstrutiva crônica (DPOC). O presente estudo teve como objetivo avaliar os níveis de expressão da MPM-2 e MPM-9 na saliva de pacientes com DPOC em comparação com indivíduos saudáveis, verificando a viabilidade de usar a saliva para a caracterização de biomarcadores específicos em DPOC. Foram selecionados pacientes com DPOC (n=16) e controles saudáveis (n=9). Em ambos os grupos foram realizados teste espirométrico e obtidas amostras de saliva de cada indivíduo. Os níveis de MPM-2 e MPM-9 na saliva foram determinados pela técnica Western blot. A MPM-2 e a MPM-9 foram significativamente maiores em pacientes com DPOC do que no grupo de indivíduos saudáveis. Foi encontrada moderada correlação negativa entre a concentração de MPM-2 e o volume expiratório forçado no primeiro segundo (r= -0,582, p=0,014) em pacientes com DPOC. Estes resultados abrem novas perspectivas para o estudo específico de biomarcadores na saliva para predizer e monitorar a obstrução ao fluxo aéreo em pacientes com DPOC

Skeletal muscle structure and function in response to electrical stimulation in moderately impaired COPD patients

Study objective: To determine the structural and functional consequences of high-frequency neuromuscular electrical stimulation (hf-NMES) in a group of moderately impaired outpatients with chronic obstructive pulmonary disease (COPD).Design: A prospective, cross-over randomized trial.Setting: An university-based, tertiary center.Patients and materials: Seventeen patients (FEV1 = 49.6 +/- 13.4% predicted, Medical Research Council dyspnoea grades II-III) underwent 6-weeks hf-NMES (50 Hz) and sham stimulation of the quadriceps femoris in a randomized, cross-over design. Knee strength was measured by isokinetic dynamometry (peak torque) and leg muscle mass (LMM) by DEXA; in addition, median cross-sectional area (CSA) of type I and fibres and capillary-fibre ratio were evaluated in the vastus lateralis. the 6-min walking distance (6MWD) was also determined.Universidade Federal de São Paulo, UNIFESP, Pulm Funct & Clin Exercise Physiol Unit, SEFIC,Div Resp Dis,Dept Med, São Paulo, BrazilUniversidade Federal de São Paulo, UNIFESP, Neuromusc Div, São Paulo, BrazilUniv Glasgow, Inst Biomed & Life Sci, Glasgow, Lanark, ScotlandUniversidade Federal de São Paulo, UNIFESP, Pulm Funct & Clin Exercise Physiol Unit, SEFIC,Div Resp Dis,Dept Med, São Paulo, BrazilUniversidade Federal de São Paulo, UNIFESP, Neuromusc Div, São Paulo, BrazilWeb of Scienc

Quality Of Sweat Test (st) Based On The Proportion Of Sweat Sodium (na) And Sweat Chloride (cl) As Diagnostic Parameter Of Cystic Fibrosis: Are We On The Right Way?

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)To assess the quality of sweat test (ST) based on the proportion of sweat sodium and sweat chloride as diagnostic parameter of cystic fibrosis (CF). Methods: A retrospective study of 5,721 sweat samples and subsequent descriptive analysis were carried out. The test was considered "of good quality" (correct) when: (i) sweat chloride was lower than 60 mEq/L, and sweat sodium was higher than sweat chloride; (ii) sweat chloride was higher than 60 mEq/L, and sweat sodium was lower than sweat chloride. Results: The study included 5,692/5,721 sweat samples of ST which had been requested due to clinical presentations compatible with CF and/or neonatal screenings with altered immunoreactive trypsinogen values. Considering the proportion of sweat sodium and sweat chloride as ST quality parameter, the test was performed correctly in 5,023/5,692 (88.2 %) sweat samples. The sweat chloride test results were grouped into four reference ranges for chloride (i) chloride >= 30 mEq/L: 3,651/5,692 (64.1 %); (ii) chloride = 40 mEq/L to = 60 mEq/L: 716/5,692 (12.6 %). In the comparative analysis, there was no association between ST quality and: (i) symptoms to indicate a ST [respiratory (p = 0.084), digestive (p = 0.753), nutritional (p = 0.824), and others (p = 0.136)], (ii) sweat weight (p = 0.416). However, there was a positive association with: (i) gender, (ii) results of ST (p < 0.001), (iii) chloride/sodium ratio (p < 0.001), (iv) subject's age at the time of ST [grouped according to category (p < 0.001) and numerical order (p < 0.001)]. For the subset of 169 patients with CF and two CFTR mutations Class I, II and/or III, in comparative analysis, there was a positive association with: (i) sweat chloride/sodium ratio (p < 0.001), (ii) sweat chloride values (p = 0.047), (iii) subject's age at the time of the ST grouped by numerical order (p = 0.001). Conclusions: Considering that the quality of ST can be assessed by levels of sweat sodium and sweat chloride, an increasing number of low-quality tests could be observed in our sweat samples. The quality of the test was associated with important factors, such as gender, CF diagnosis, and subjects' age.11103FALM: Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [2011/12939-4, 2015/12858-5]Fundo de Apoio a Pesquisa ao Ensino e a Extensao da Universidade Estadual de Campinas [0648/2015]JDR: FAPESP [2011/18845-1]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP