Objective: To evaluate diaphragmatic mobility in relation to lung function, respiratory muscle strength, dyspnea, and physical activity in daily life (PADL) in patients with COPD. Methods: We included 25 patients with COPD, classified according to the Global Initiative for Chronic Obstructive Lung Disease criteria, and 25 healthy individuals. For all of the participants, the following were evaluated: anthropometric variables, spirometric parameters, respiratory muscle strength, diaphragmatic mobility (by X-ray), PADL, and the perception of dyspnea. Results: In the COPD group, diaphragmatic mobility was found to correlate with lung function variables, inspiratory muscle strength, and the perception of dyspnea, whereas it did not correlate with expiratory muscle strength or PADL. Conclusions: In patients with COPD, diaphragmatic mobility seems to be associated with airway obstruction and lung hyperinflation, as well as with ventilatory capacity and the perception of dyspnea, although not with PADL.

Keywords: Pulmonary disease, chronic obstructive; Diaphragm; Spirometry; Dyspnea; Maximal respiratory pressures.

Objective: To evaluate the magnitude of diurnal changes in the parameters of pulmonary function and respiratory muscle strength/endurance in a sample of patients with COPD. Methods: A group of 7 patients underwent spirometry, together with determination of MIP and MEP, at two distinct times (between 8:00 and 8:30 a.m. and between 4:30 and 5:00 p.m.) on a single day. Between assessments, the patients remained at rest in the laboratory. Results: In accordance with the Global Initiative for Chronic Obstructive Pulmonary Disease staging system, COPD was classified as moderate, severe, and very severe in 1, 3, and 3 of the patients, respectively. From the first to the second assessment, there were significant decreases in FVC, FEV1, and MEP (of 13%, 15%, and 10%, respectively), as well as (less than significant) decreases in PEF, MIP, and maximal voluntary ventilation (of 9%, 3%, and 11%, respectively). Conclusions: In this sample of COPD patients, there were diurnal variations in the parameters of pulmonary function and respiratory muscle strength. The values of FEV1, FVC, and MEP were significantly lower in the afternoon than in the morning.

Keywords: Pulmonary disease, chronic obstructive; Respiratory function tests; Respiratory muscles.

Objective: To determine whether the level of physical activity in daily life (PADL) is associated with pulmonary function in adult smokers. Methods: We selected 62 adult smokers from among the participants of an epidemiological study conducted in the city of Santos, Brazil. The subjects underwent forced spirometry for pulmonary function assessment. The level of PADL was assessed by the International Physical Activity Questionnaire and triaxial accelerometry, the device being used for seven days. The minimum level of PADL, in terms of quantity and intensity, was defined as 150 min/week of moderate to vigorous physical activity. Correlations between the studied variables were tested with Pearson's or Spearman's correlation coefficient, depending on the distribution of the variables. We used linear multiple regression in order to analyze the influence of PADL on the spirometric variables. The level of significance was set at 5%. Results: Evaluating all predictors, corrected for confounding factors, and using pulmonary function data as outcome variables, we found no significant associations between physical inactivity, as determined by accelerometry, and spirometric indices. The values for FVC were lower among the participants with arterial hypertension, and FEV1/FVC ratios were lower among those with diabetes mellitus. Obese participants and those with dyslipidemia presented with lower values for FVC and FEV1. Conclusions: Our results suggest that there is no consistent association between physical inactivity and pulmonary function in adult smokers. Smoking history should be given special attention in COPD prevention strategies, as should cardiovascular and metabolic comorbidities.

Keywords: Smoking; Respiratory function tests; Motor activity; Accelerometry.

Objective: To evaluate characteristics of physical activities in daily life in COPD patients in Brazil, correlating those characteristics with physiological variables. Methods: Physical activities in daily life were evaluated in 40 COPD patients (18 males; 66 ± 8 years of age; FEV1 = 46 ± 16 % of predicted; body mass index = 27 ± 6 kg/m2) and 30 healthy age- and gender-matched subjects, using a multiaxial accelerometer-based sensor for 12 h/day on two consecutive days. We also assessed maximal and functional exercise capacity, using the incremental exercise test and the six-minute walk test (6MWT), respectively; MIP and MEP; peripheral muscle force, using the one-repetition maximum test and the handgrip test; quality of life, using the Saint George's Respiratory Questionnaire (SGRQ); functional status, using the London Chest Activity of Daily Living questionnaire; and dyspnea sensation, using the Medical Research Council (MRC) scale. Results: Mean walking time/day was shorter for COPD patients than for the controls (55 ± 33 vs. 80 ± 28 min/day; p = 0.001), as movement intensity was lower (1.9 ± 0.4 vs. 2.3 ± 0.6 m/s2; p = 0.004). The COPD patients also tended to spend more time seated (294 ± 114 vs. 246 ± 122 min/day, p = 0.08). Walking time/day correlated with the 6MWT (r = 0.42; p = 0.007) and maximal workload (r = 0.41; p = 0.009), as well as with age, MRC scale score and SGRQ activity domain score (−0.31 ≤ r ≤ −0.43; p ≤ 0.05 for all). Conclusions: This sample of Brazilian patients with COPD, although more active than those evaluated in studies conducted in Europe, were less active than were the controls. Walking time/day correlated only moderately with maximal and functional exercise capacity.

Keywords: Pulmonary disease, chronic obstructive; Motor activity; Exercise tolerance.

Objective: To evaluate lung function and inspiratory muscle strength, correlating them with exercise tolerance, in obese individuals with obstructive sleep apnea syndrome (OSAS). Methods: The sample comprised 31 adult subjects with moderate-to-severe OSAS diagnosed by polysomnography. We used spirometry to measure FVC, FEV1, and FVC/FEV1 ratio, using pressure manometry to measure MIP and MEP. The incremental shuttle walk test (ISWT) and the six-minute walk test (6MWT) were used in order to determine functional exercise capacity. Results: In this sample, the mean values for FVC (% of predicted), FEV1 (% of predicted): MIP, and MEP were 76.4 ± 12.3%, 80.1 ± 6.3%, 60.0 ± 21.9 cmH2O, and 81.3 ± 22.2 cmH2O, respectively. The mean distances covered on the ISWT and 6MWT were 221 ± 97 m and 480.8 ± 67.3 m, respectively. The ISWT distance showed moderate positive correlations with FVC (r = 0.658; p = 0.001) and FEV1 (r = 0.522; p = 0.003). Conclusions: In this sample of obese subjects with untreated OSAS, lung function, inspiratory muscle strength, and exercise tolerance were all below normal. In addition, we found that a decline in lung function, but not in respiratory muscle strength, was associated with exercise tolerance in these patients.

Keywords: Sleep apnea syndromes; Exercise tolerance; Respiratory function tests; Respiratory muscles.

Background: Pulmonary rehabilitation is widely recommended for the treatment of chronic obstructive pulmonary disease. Objective: To evaluate the efficacy of pulmonary rehabilitation in improving exercise capacity, respiratory muscle strength and quality of life of chronic obstructive pulmonary disease patients. Method: This was an open, non-randomized clinical trial involving 27 clinically stable ex-smokers with chronic obstructive pulmonary disease who were enrolled in a pulmonary rehabilitation program. All were evaluated before and after pulmonary rehabilitation. Results: Mean age was 65 ± 5 years, mean body mass index was 25 ± 4 kg/m2, mean forced expiratory volume in one second was 55 ± 25% of predicted, mean ratio between forced expiratory volume in one second and forced vital capacity was 50 ± 12%, and mean arterial oxygen tension was 70 ± 7 mmHg. Comparison of pre- and post-pulmonary rehabilitation values revealed improvement in the distance walked in the 6-minute walk test (513 ± 99 m vs. 570 ± 104 m), maximum upper limb load (2 ± 1 kg vs. 3 ± 1 kg) and maximal inspiratory pressure (-89 ± 23 cmH2O vs. -102 ± 23 cmH2O), as well as in the activity domain, impact domain and total score on the Saint George's Respiratory Questionnaire. Conclusion: Pulmonary rehabilitation, when performed with care and with a focus on physical training, is efficacious in increasing not only the distance walked in the 6-minute walk test but maximum upper limb load, maximal inspiratory pressure and quality of life as well.

Keywords: Key words: Pulmonary rehabilitation. Chronic obstructive pulmonary disease. Quality of life. Respiratory muscles.

Objective: To evaluate the ability of COPD patients to perform activities of daily living (ADL); to identify barriers that prevent these individuals from performing ADL; and to correlate those barriers with dyspnea severity, six-minute walk test (6MWT), and an ADL limitation score. Methods: In COPD patients and healthy, age-matched controls, the number of steps, the distance walked, and walking time were recorded with a triaxial accelerometer, for seven consecutive days. A questionnaire regarding perceived barriers and the London Chest Activity of Daily Living (LCADL) scale were used in order to identify the factors that prevent the performance of ADL. The severity of dyspnea was assessed with two scales, whereas submaximal exercise capacity was determined on the basis of the 6MWT. Results: We evaluated 40 COPD patients and 40 controls. In comparison with the control values, the mean walk time was significantly shorter for COPD patients (68.5  25.8 min/day vs. 105.2  49.4 min/day; p < 0.001), as was the distance walked (3.9  1.9 km/day vs. 6.4  3.2 km/day; p < 0.001). The COPD patients also walked fewer steps/day. The most common self-reported barriers to performing ADL were lack of infrastructure, social influences, and lack of willpower. The 6MWT distance correlated with the results obtained with the accelerometer but not with the LCADL scale results. Conclusions: Patients with COPD are less active than are healthy adults of a comparable age. Physical inactivity and the barriers to performing ADL have immediate implications for clinical practice, calling for early intervention measures.

Keywords: Pulmonary disease, chronic obstructive; Activities of daily living; Exercise tolerance.

Objective: Barriers to physical activity can affect the functional capacity and quality of life of patients with pulmonary hypertension (PH). This study aimed to identify the main barriers to physical activity in patients with PH and to examine whether those barriers are related to functional capacity, echocardiographic variables, or quality of life. Methods: This was a cross-sectional observational study involving 70 patients. Participants scored seven potential barriers to their activities, with a score = 5 indicating a significant barrier. Participants completed the Medical Outcomes Study 36-item Short-Form Health Survey (SF-36) and Manchester Respiratory Activity of Daily Living questionnaire, as well as the six-minute walk test. Correlation analysis, univariate analysis and multiple logistic regression were performed. Results: As a perceived barrier to physical activity, 'lack of will' or 'lack of energy' was cited by 67% of the patients. The 'lack of will' barrier was found to correlate with all SF-36 domains except bodily pain. We also identified a correlation between the SF-36 vitality domain and the barriers 'lack of energy', 'lack of will' and 'lack of structure'. The logistic regression analysis indicated that the vitality domain correlated significantly with the barriers 'social influence', 'lack of energy', 'lack of will', and 'lack of structure'. For each unit decrease in the vitality score, there was a 10% increase in the probability of citing the barrier 'lack of will'. No significant correlations were identified between any of the perceived barriers and echocardiographic parameters. Conclusions: The perceived barrier most commonly reported was 'lack of will/energy', which correlated with almost all SF-36 domains, especially vitality. The 'lack of will' barrier also correlated with functional capacity.

Keywords: Pulmonary arterial hypertension; Exercise; Motivation; Quality of life; Surveys and questionnaires; Walk test.

Objective: To evaluate respiratory muscle strength and six-minute walk test (6MWT) variables in patients with uncontrolled severe asthma (UCSA). Methods: This was a cross-sectional study involving UCSA patients followed at a university hospital. The patients underwent 6MWT, spirometry, and measurements of respiratory muscle strength, as well as completing the Asthma Control Test (ACT). The Mann-Whitney test was used in order to analyze 6MWT variables, whereas the Kruskal-Wallis test was used to determine whether there was an association between the use of oral corticosteroids and respiratory muscle strength. Results: We included 25 patients. Mean FEV1 was 58.8  21.8% of predicted, and mean ACT score was 14.0  3.9 points. No significant difference was found between the median six-minute walk distance recorded for the UCSA patients and that predicted for healthy Brazilians (512 m and 534 m, respectively; p = 0.14). During the 6MWT, there was no significant drop in SpO2. Mean MIP and MEP were normal (72.9  15.2% and 67.6  22.2%, respectively). Comparing the patients treated with at least four courses of oral corticosteroids per year and those treated with three or fewer, we found no significant differences in MIP (p = 0.15) or MEP (p = 0.45). Conclusions: Our findings suggest that UCSA patients are similar to normal subjects in terms of 6MWT variables and respiratory muscle strength. The use of oral corticosteroids has no apparent impact on respiratory muscle strength.

Objective: To investigate parameters of lung function and respiratory muscle strength in different stages of Parkinson's disease (PD), as well as to determine their correlation with motor function and quality of life. Methods: This was a cross-sectional study conducted at a referral center for PD in the city of Recife, Brazil. Respiratory muscle strength and lung function, as well as their relationship with motor function and quality of life, were evaluated in patients with PD, stratified by the level of severity, and were compared with the data obtained for a control group. After confirming the normality of data distribution, we performed one-way ANOVA with a post hoc t-test. Results: The sample comprised 66 individuals, in two groups: PD (n = 49) and control (n = 17). All of the parameters investigated showed inverse correlations with PD severity, and there were significant differences among the levels of severity, as well as between the PD and control groups, in terms of the MIP, MEP, FVC, FEV1, and FEF25-75%. The lung function parameters also showed moderate to weak inverse correlations with bradykinesia and rigidity. On a quality of life questionnaire, the total score and mobility domain score both presented a moderate inverse correlation with FVC, FEV1, PEF, and MEP. Conclusions: Respiratory muscle strength and some lung function parameters are impaired from the early stages of PD onward, bradykinesia and rigidity being the cardinal signs that correlate most strongly with impairment of those parameters. Such alterations negatively affect the quality of life of patients with PD.

Keywords: Parkinson disease; Respiratory mechanics; Maximum respiratory pressures; Quality of life.

Objective: To evaluate pulmonary function and respiratory muscle strength in chronic renal failure patients, correlating these variables with hemodialysis-related weight fluctuation; to study the correlation between the duration of hemodialysis and potential respiratory alterations. Methods: Seventeen patients (median age, 47 years; interquartile range, 41-52 years), submitted to three weekly hemodialysis sessions for a median of 27 months (interquartile range, 14-55) were evaluated. Twelve of the patients were male. The patients underwent spirometry. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) were measured prior to and after the first hemodialysis session of the week. Body weight was quantified prior to and after each of the three weekly sessions. Results: Before the first hemodialysis session of the week, 8 patients presented mild restrictive defect, which normalized after the session in 2 of those patients. After dialysis, there was a significant increase in forced vital capacity (p = 0.02) and a significant decrease in body weight (p = 0.0001). Weight fluctuation over 3 days without hemodialysis tended to correlate with the variation in forced vital capacity in the first weekly session (r = 0.47; p = 0.055). Duration of hemodialysis correlated with predialysis MIP (r = −0.3; p = 0.03) and MEP (r = −0.63; p = 0.006). Conclusions: More pronounced weight gain in the interdialytic period is associated with worsening of lung function, which is almost fully reversible by hemodialysis. In addition, longer duration of hemodialysis is associated with decreased respiratory muscle strength.

Keywords: Spirometry; Respiratory muscles/physiopathology; Kidney failure, chronic; Renal dialysis.

Objective: Impaired respiratory mechanics and gas exchange may contribute to sleep disturbance in patients with COPD. We aimed to assess putative associations of different domains of lung function (airflow limitation, lung volumes, and gas exchange efficiency) with polysomnography (PSG)-derived parameters of sleep quality and architecture in COPD. Methods: We retrospectively assessed data from COPD 181 patients = 40 years of age who underwent spirometry, plethysmography, and overnight PSG. Univariate and multivariate linear regression models predicted sleep efficiency (total sleep time/total recording time) and other PSG-derived parameters that reflect sleep quality. Results: The severity of COPD was widely distributed in the sample (post-bronchodilator FEV1 ranging from 25% to 128% of predicted): mild COPD (40.3%), moderate COPD (43.1%), and severe-very severe COPD (16.6%). PSG unveiled a high proportion of obstructive sleep apnea (64.1%) and significant nocturnal desaturation (mean pulse oximetry nadir = 82.2% ± 6.9%). After controlling for age, sex, BMI, apnea-hypopnea index, nocturnal desaturation, comorbidities, and psychotropic drug prescription, FEV1/FVC was associated with sleep efficiency (ß = 25.366; R2 = 14%; p < 0.001), whereas DLCO predicted sleep onset latency (ß = -0.314; R2 = 13%; p < 0.001) and rapid eye movement sleep time/total sleep time in % (ß = 0.085; R2 = 15%; p = 0.001). Conclusions: Pulmonary function variables reflecting severity of airflow and gas exchange impairment, adjusted for some potential confounders, were weakly related to PSG outcomes in COPD patients. The direct contribution of the pathophysiological hallmarks of COPD to objectively measured parameters of sleep quality seems to be less important than it was previously assumed.

Keywords: Pulmonary disease, chronic obstructive; Respiratory function tests; Sleep; Sleep apnea, obstructive; Comorbidity.

Objective: To analyze the effects of Pilates mat exercises in patients with cystic fibrosis (CF). Methods: This was a clinical trial involving 19 CF patients recruited from either the CF Outpatient Clinic of the State University at Campinas Hospital de Clínicas or the Children's Institute of the University of São Paulo School of Medicine Hospital das Clínicas. All of the patients performed Pilates mat exercises for four months (one 60-min session per week). The variables studied (before and after the intervention) were respiratory muscle strength, MIP, MEP, FVC, and FEV1. Results: After the intervention, MIP was significantly higher in the male patients (p = 0.017), as were MIP and MEP in the female patients (p = 0.005 and p = 0.007, respectively). There were no significant differences between the pre- and post-intervention values of FVC or FEV1, neither in the sample as a whole nor among the patients of either gender. Conclusions: Our results show that Pilates mat exercises have beneficial effects on respiratory muscle strength in CF patients. (Brazilian Registry of Clinical Trials - ReBEC; identification number RBR-86vp8x [http://www.ensaiosclinicos.gov.br])

Keywords: Cystic fibrosis; Muscle strength; Exercise movement techniques; Respiratory function tests.

Objective: To determine the effect that re-education of the thoracic and abdominal muscles has on the respiratory muscle strength of patients with cystic fibrosis evaluated over time at the Cystic Fibrosis Outpatient Clinic of the Universidade Católica de Brasília (Catholic University of Brasília). Methods: The sample consisted of 29 cystic fibrosis patients, characterized based on anthropometric, genetic and bacterial colonization data. The patients were submitted to physical therapy sessions, involving re-education of the respiratory muscles, twice a week for four months. Spirometry, pressure manometry and anthropometry were performed before and after each session. Results: Comparing baselines values to those obtained after physical therapy, increases in maximum inspiratory pressure and maximum expiratory pressure were observed in all patients, those without any obstructive respiratory disease and those with mild obstructive respiratory disease (p < 0.05). A positive correlation between age and maximum expiratory pressure was observed for most of the patients. Maximum inspiratory pressure correlated positively with age only in the group with mild obstructive respiratory disease (p = 0.012; r = 0.817). In female patients and in the group of patients without obstructive respiratory disease, a negative correlation was observed between maximum expiratory pressure and colonization with Pseudomonas aeruginosa (p = 0.036; r = -0.585). Conclusion: Use of the thoracic and abdominal muscle re-education technique increased respiratory muscle strength in the cystic fibrosis patients studied, a finding that underscores the importance of including physical therapy in the treatment of these patients.

Keywords: Cystic fibrosis/rehabilitation; Physical therapy technique; Respiratory muscles; Forced expiratory volume; Inspiratory capacity; Vital capacity

Objective: To compare equations for predicting peak quadriceps femoris (QF) muscle force; to determine the agreement among the equations in identifying QF muscle weakness in COPD patients; and to assess the differences in characteristics among the groups of patients classified as having or not having QF muscle weakness by each equation. Methods: Fifty-six COPD patients underwent assessment of peak QF muscle force by dynamometry (maximal voluntary isometric contraction of knee extension). Predicted values were calculated with three equations: an age-height-weight-gender equation (Eq-AHWG); an age-weight-gender equation (Eq-AWG); and an age-fat-free mass-gender equation (Eq-AFFMG). Results: Comparison of the percentage of predicted values obtained with the three equations showed that the Eq-AHWG gave higher values than did the Eq-AWG and Eq-AFFMG, with no difference between the last two. The Eq-AHWG showed moderate agreement with the Eq-AWG and Eq-AFFMG, whereas the last two also showed moderate, albeit lower, agreement with each other. In the sample as a whole, QF muscle weakness (< 80% of predicted) was identified by the Eq-AHWG, Eq-AWG, and Eq-AFFMG in 59%, 68%, and 70% of the patients, respectively (p > 0.05). Age, fat-free mass, and body mass index are characteristics that differentiate between patients with and without QF muscle weakness. Conclusions: The three equations were statistically equivalent in classifying COPD patients as having or not having QF muscle weakness. However, the Eq-AHWG gave higher peak force values than did the Eq-AWG and the Eq-AFFMG, as well as showing greater agreement with the other equations.

Keywords: Pulmonary disease, chronic obstructive; Muscle strength; Quadriceps muscle; Reference values.

Objective: To compare diaphragmatic mobility, lung function, and respiratory muscle strength between COPD patients with and without thoracic hyperkyphosis; to determine the relationship of thoracic kyphosis angle with diaphragmatic mobility, lung function, and respiratory muscle strength in COPD patients; and to compare diaphragmatic mobility and thoracic kyphosis between male and female patients with COPD. Methods: Participants underwent anthropometry, spirometry, thoracic kyphosis measurement, and evaluation of diaphragmatic mobility. Results: A total of 34 patients with COPD participated in the study. Diaphragmatic mobility was significantly lower in the group of COPD patients with thoracic hyperkyphosis than in that of those without it (p = 0.002). There were no statistically significant differences between the two groups of COPD patients regarding lung function or respiratory muscle strength variables. There was a significant negative correlation between thoracic kyphosis angle and diaphragmatic mobility (r = −0.47; p = 0.005). In the sample as a whole, there were statistically significant differences between males and females regarding body weight (p = 0.011), height (p < 0.001), and thoracic kyphosis angle (p = 0.036); however, there were no significant differences in diaphragmatic mobility between males and females (p = 0.210). Conclusions: Diaphragmatic mobility is lower in COPD patients with thoracic hyperkyphosis than in those without it. There is a negative correlation between thoracic kyphosis angle and diaphragmatic mobility. In comparison with male patients with COPD, female patients with COPD have a significantly increased thoracic kyphosis angle.

Keywords: Pulmonary disease, chronic obstructive; Kyphosis; Diaphragm.