Left ventricular concentric remodeling in COPD patients: A cross-sectional observational study.

OBJECTIVE: To investigate the association between left ventricular structure and disease severity in COPD patients. METHODS: Twenty-eight COPD patients were stratified according to the disease severity, using the BODE index, into Lower (n=17) and Higher (n=11) groups, composed of patients with lower severity (BODE <5) and higher severity (BODE ≥5), respectively. Left ventricle (LV) was assessed by 2D-echocardiography. BODE index was calculated using body mass index (BMI); forced expiratory volume in the first second (FEV1, %); modified Medical Research Council (mMRC) and distance walked during 6-minute walk test (6MWD). RESULTS: Patients in the Higher group showed lower oxygen arterial saturation (p=0.02), FEV1 (p<0.01) and 6MWD (p=0.02) and higher value of relative posterior wall thickness (RWT) compared to Lower group (p=0.02). There were significant associations between LV end-systolic diameter (LVESD) and BODE index (r=-0.38, p=0.04), LV end-diastolic diameter (LVEDD) and FEV1 (r=0.44, p=0.02), LVEDD and BMI (r=0.45, p=0.02), LVESD and BMI (r=0.54, p=0.003) and interventricular septal thickness and 6MWD (r=-0.39, p=0.04). CONCLUSIONS: More severe COPD patients, BODE score ≥5, may have higher RWT, featuring a possible higher concentric remodeling of LV in this group. Besides that, a greater disease severity may be related to LV chamber size reduction.

Inspiratory muscle endurance is similarly reduced in the early and late stages of chronic Chagas heart disease.

OBJECTIVE: Inspiratory muscle strength (IMS) appears to be reduced in subjects with chronic Chagas heart disease (CHD), especially in the presence of heart failure (HF). However, only one study about IMS and inspiratory muscle endurance (IME) in those with CHD without heart failure is available. This study aimed to compare IMS and IME in subjects with CHD in the presence and absence of HF. METHODS: This is a cross-sectional study in which 30 CHD adult patients were divided into CHD-CC group (initial phase of CHD, without HF; n = 15) and CHD-HF group (advanced phase of CHD, with HF; n = 15). We assessed IMS by maximum inspiratory pressure (MIP) and IME by incremental (Pthmax) and constant load (TLim) tests. Reduced IMS and IME were considered by predicted MIP values <70% and Pthmax/MIP <75%, respectively. RESULTS: Inspiratory muscle weakness (IMW) was more frequent in CHD-HF than in CHD-CC (46.7% vs. 13.3%; p = 0.05), and both groups had high frequencies of reduced IME (93.3% CHD-CC vs. 100.0% CHD-HF; p = 0.95). Age-adjusted logistic regression analysis using HF as a dependent variable showed that HF was associated with an increased chance of IMW compared with the CHD-CC group (OR = 7.47; p = 0.03; 95% CI 1.20-46.19). CONCLUSION: This study suggests that, in patients with CHD, HF is associated with IMW, and that reduction of IME is already present in the initial phase, similar to the advanced phase with HF.

Effect of Pulmonary Rehabilitation on Exercise Capacity, Dyspnea, Fatigue, and Peripheral Muscle Strength in Patients With Post-COVID-19 Syndrome: A Systematic Review and Meta-analysis.

OBJECTIVE: To establish the effects of pulmonary rehabilitation (PR) in patients with persistent symptoms after COVID-19 infection. In addition, to compare the modalities of PR services (face-to-face and telerehabilitation) and the duration of PR in weeks (4-8 weeks and >8 weeks). DATA SOURCES: PubMed/MEDLINE, Embase (Elsevier), Central/Cochrane Library, SciELO Citation Index (Web of Science), and CINAHL. STUDY SELECTION: Studies determining the effects of PR in patients with post-COVID-19 syndrome were included and grouped according to PR delivery modality. DATA EXTRACTION: Data extraction and quality assessment were independently performed by 2 reviewers. The methodological quality was assessed using the Cochrane Risk of Bias Tool 1 (RoB-1). DATA SYNTHESIS: The literature search retrieved 1406 articles, of which 7 studies explored the effects of PR on patients with post-COVID-19 syndrome, with 188 patients randomized to PR. The mean age of participants was 50 years and 49% were women. Meta-analysis showed an increase in exercise capacity with PR compared with control (6-minute walking test: mean difference: 60.56 m, 95% confidence interval: 40.75-80.36), a reduction in fatigue (Fatigue Severity Scale: -0.90, -1.49 to -0.31) but no change in dyspnea (-0.57, -1.32 to 0.17) and muscle strength (3.03, -1.89 to 7.96). There were no differences between telerehabilitation and face-to-face PR regarding effects on peripheral muscle strength (P=.42), dyspnea (P=.83), and fatigue (P=.34). There were no differences between programs 4-8 weeks and >8 weeks regarding exercise capacity (P=.83), peripheral muscle strength (P=.42), and dyspnea (P=.76). CONCLUSIONS: PR improves exercise capacity and reduces fatigue in patients with post-COVID-19 syndrome. Duration of PR (4-8 weeks vs > 8 weeks) or PR modality (telerehabilitation vs face-to-face) did not affect outcomes but data were limited and based on subgroup analysis. Further evidence is required to determine the optimal delivery mode and duration of PR for post-COVID-19 syndrome.

The six-minute step test can predict COPD exacerbations: a 36-month follow-up study.

The six-minute step test (6MST) has been shown to be effective in assessing exercise capacity in individuals with COPD regardless of severity and, despite its easy execution, accessibility and validity, information on the prognostic power of this test remains uncertain. The aim of this study is to investigate whether the 6MST can predict the occurrence of exacerbations in patients with COPD. This is a prospective cohort study with a 36-month follow-up in patients with COPD. All patients completed a clinical assessment, followed by pulmonary function testing and a 6MST. The 6MST was performed on a 20 cm high step; heart rate, blood pressure, oxygen saturation, BORG dyspnea and fatigue were collected. Sixty-four patients were included in the study, the majority being elderly men. Performance on the 6MST demonstrated lower performance compared to normative values proposed in the literature, indicating a reduced functional capacity. Kaplan Meier analysis revealed that ≤ 59 steps climbed during the 6MST was a strong predictor of COPD exacerbation over a 36-month follow-up. We have identified a minimal threshold number of steps (≤ 59) obtained through the 6MST may be able predict the risk of exacerbations in patients with COPD.

Phenotyping cardiopulmonary exercise testing measures in heart failure with reduced ejection fraction: A comparison between Italy and Brazil.

BACKGROUND: While patients with heart failure (HF) with reduced left ventricular ejection fraction (HFrEF) constitutes a global health crisis the incidence, prevalence and prognosis of the disease may differ depending on the continent and country. OBJECTIVE: To profile, analyze and compare cardiopulmonary exercise testing (CPET) data of patients with HFrEF between Italian and Brazilian cohorts. METHODS: In this observational study, a total of 630 patients with clinical and functional diagnosis of HFrEF (315 patients from Brazil and 315 patients from Italy) performed CPET. RESULTS: Although Brazilian patients were slightly younger (Brazil 60±10 vs Italy 64±11 p<0.001) with a better peak oxygen consumption (V̇O2), circulatory power and left ventricular ejection fraction (LVEF) (p<0.01), ventilatory inefficiency and oscillation ventilation was higher when compared to the Italian cohort. When stratifying patients with LVEF≤30 % and age≥60 years, Brazilian patients presented worse ventilatory efficiency, and lower peak V̇O2 compared to the Italian cohort. CONCLUSION: Patients with HFrEF from Brazil exhibited higher ventilatory inefficiency and a greater prevalence of oscillatory ventilation during CPET compared to patients with the same diagnosis from Italy.

Inspiratory Muscle Strength in Chagas Cardiomyopathy: A Systematic Scoping Review.

The increase in inflammatory markers associated with persistent chronic fibrosing myocarditis, a characteristic of chronic Chagas disease, can result in a reduction in inspiratory muscle strength (IMS) in Chagas cardiomyopathy (CC). However, literature in this field is still scarce. This review aimed to map and summarize the evidence regarding IMS in patients with CC. The inclusion criteria included reports with adult participants with a CC diagnosis, with or without heart failure (HF). The core concept examined was the maximum inspiratory pressure evaluated in the untrained and trained groups in the pre-training period. The context was open, including but not limited to hospitals and health centers. Two authors independently identified eligible studies and extracted the data. Descriptive synthesis was used as the primary strategy for analyzing the results. Nine studies (five clinical trials, three cross-sectional, and one cohort) were included. The CC classification differed among the studies, with no mention of HF in five and no CC staging specification in six. IMS was assessed using a manovacuometer, and only six studies analyzed and interpreted the data concerning the predicted values. The CC population with HF appeared to have impaired IMS. All studies involved only Brazilian volunteers. In conclusion, randomized clinical trials evaluating IMS and the effects of inspiratory muscle training need to be conducted to better understand the prevalence and risk of inspiratory muscle weakness in the CC population, as well as the effects of training. Such studies should be conducted at different stages of CC in different populations and countries.

Regular Physical Exercise Adherence Scale (REPEAS): a new instrument to measure environmental and personal barriers to adherence to regular physical exercise.

OBJECTIVE: To create, develop, and validate a scale that identifies the environmental and personal barriers that make it difficult to adhere to the practice of physical exercise on a regular basis in a population of Brazilian adults. METHODS: We include adult individuals, aged 18-59 years, practitioners or former practitioners of physical exercise, with Brazilian Portuguese as their mother tongue. In the development and validation phases of the process, 6 specialists in the field of the health assessed the content validity: firstly, the specialists were asked to freely list the questions they would ask to investigate the barriers to adherence to regulating physical activity. Secondly, after compiling all the suggestions listed and eliminating suggestions with similar content, the items suggested in the first round were sent to the specialists so that an evaluation of all questions using a 5-point Likert scale and the content validity coefficient was calculated. We then evaluated the structural validity, construct validity, reliability, internal consistency, and ceiling and floor effects of the Regular Physical Exercise Adherence Scale (REPEAS). RESULTS: Sixteen items were proposed to measure the factors that make it difficult to adhere to the regular practice of physical exercise. The internal structure of the REPEAS initially tested was based on the theoretical proposal of creating the instrument with two domains. After the structural analysis, we used the modification indices to identify the redundant items of the instrument. Consequently, the final version of the REPEAS after factor analysis had 12 items. Thus, the structure with 2 domains and 12 items presented adequate fit indices. With regard to construct validity, the REPEAS scores were compared in two distinct groups: irregular practitioners/ex-practitioners versus regular practitioners of physical exercise, in which a significant difference could be observed between groups (p < 0.001) for both the domains. Acceptable reliability was observed for the environment and personal domains, with ICC values of 0.86 and 0.94, in the same order. For internal consistency, Cronbach's alpha value was 0.908 (environmental domain) and 0.915 (personal domain), these values being adequate for the REPEAS. CONCLUSION: The REPEAS is a scale with a valid two-dimensional internal structure, consisting of 12 items, reliable and with a valid construct, which supports its use in the clinical, epidemiological, and research contexts in Brazil.

Impact of long COVID on the heart rate variability at rest and during deep breathing maneuver.

While the majority of individuals with coronavirus disease 2019 (COVID-19) recover completely, a significant percentage experience persistent symptom, which has been characterized as Long COVID and may be associated with cardiac and autonomic dysfunction. We evaluated heart rate variability (HRV) at rest and during deep-breathing (M-RSA) in patients with Long COVID. Case-control design involved 21 patients with Long COVID and 20 controls; the HRV was evaluated (POLAR system) at rest in the supine position and during M-RSA and expressed in time domain and non-linear analysis. In the supine position we found a reduction HRV measures in Long COVID' patients compared to controls for: Mean_iRR (p < 0.001), STD_iRR (p < 0.001); STD_HR (p < 0.001); SD1 (p < 0.001); SD2 (p < 0.001); alpha2 (p < 0.001). In the M-RSA we found reduction Mean_iRR (p < 0.001), STD_iRR (p < 0.001), STD_HR (p < 0.001), rMSSD (p < 0.001), RR_tri-index (p < 0.001) in Long COVID' patients except for highest Mean_HR p < 0.001. In conclusion, Long COVID reduced HRV at rest and during deep breathing. These findings may imply impairment of cardiac autonomic control when symptoms of COVID-19 persist following initial recovery.

Case-Finding tool for COPD in LMIC (COLA) - translation and cross-cultural adaptation into Brazilian Portuguese language.

OBJECTIVE: To translate and cross-culturally adapt the COPD in Low- and middle-income countries (LMICs) Assessment (COLA) questionnaire into Brazilian Portuguese, a case-finding instrument for chronic obstructive pulmonary disease (COPD). METHODS: Translation and cross-cultural adaptation were completed in six steps: the original version was translated into Brazilian Portuguese by two native speakers of the target language; the translated versions were synthesized; back-translation was performed by two native speakers of the original language; the back-translation and the Brazilian Portuguese version of the COLA were reviewed and harmonized by an expert committee of specialists; and, then, the pre-final version was tested by 30 health professionals who were asked if the items were clear to understand. The acceptability, clarity, and understandability of the translated version were evaluated. A final review of the questionnaire was produced by the authors and approved by the author of the original questionnaire. RESULTS: Some idiomatic, semantic, and experiential inconsistencies were identified and properly adjusted. Item 3 was considered the most unclear item (23,3%). Items 7, 8, and 9 presented clarity above 80% (93%, 90%, and 90%, respectively). Suggestions were discussed and incorporated into the tool and COLA was found to be clear and easy to understand. CONCLUSIONS: The Brazilian version of the COLA was easily understood by healthcare professionals and adapted to Brazilian culture. Translation and cultural adaptation of the COLA instrument into Brazilian Portuguese can be an important case-finding instrument for chronic obstructive pulmonary disease in Brazil.

Predictors of cardiopulmonary exercise testing in COPD patients according to the Weber classification.

BACKGROUND: Weber classification stratifies cardiac patients based on peak oxygen consumption (V̇O2), the gold-standard measure of exercise capacity. OBJECTIVE: To determine if Weber classification is a useful tool to discriminate clinical phenotypes in COPD patients and to evaluate if disease severity and other clinical measures can predict V̇O2peak. METHODS: Three hundred and six COPD patients underwent cardiopulmonary exercise testing (CPX) and were divided according to Weber class: 1) Weber A (n = 34); 2) Weber B (n = 88); 3) Weber C (n = 138); and 4) Weber D (n = 46). RESULTS: Weber class D patients demonstrated a reduced V̇O2 peak, heart rate (HR), minute ventilation (V̇E), oxygen (O2) pulse, circulatory power (CP), oxygen uptake efficiency slope (OUES), oxygen saturation (SpO2%), delta (Δ)HR and ΔSpO2 when compared to Weber A and B (p<0.05). Moreover, Dyspnea and the V̇E/carbon dioxide production (V̇CO2) slope were higher in Weber D compared with Weber C and A (p<0.001). Hierarchical regression analysis demonstrated significant predictors of V̇O2peak (R2= 0.131; Adj R 2 = 1.25), including HR (ß=0.5757; t = 5.7; P<0.001) and forced expiratory volume in one second (FEV1) (ß=0.119; t = 2.16; P<0.03). Among the Weber C + D groups, predictors of V̇O2peak (R = 0.78; R2= 0.60; Adj R2 =0.59), dyspnea (ß=0.076; t = 1.111; P<0.27) and maximal voluntary ventilation (MVV) (ß=0.75; t = 1.14; P<0.00). CONCLUSION: Weber classification may be a useful tool to stratify cardiorespiratory fitness in COPD patients. Other clinical measures may be useful in predicting peak V̇O2 in mild-to-severe COPD, moreover different phenotypes may be important tool to improve physical capacity of chronic disease patients.

Inter- and intrarater reliability of short-term measurement of heart rate variability on rest in chronic obstructive pulmonary disease (COPD).

BACKGROUND: Individuals with COPD have an imbalance of cardiac autonomic control. In this context, HRV is considered an important tool for assessing cardiac sympathetic and parasympathetic balance, however it is a dependent evaluator measure and subject to methodological biases that may compromise the interpretation of results. OBJECTIVE: This study examines the inter- and intrarater reliability of HRV parameters derived from short-term recordings in individuals with COPD. METHODOLOGY: Fifty-one individuals of both genders with COPD clinical diagnosis confirmed by the pulmonary function test and aged ≥50 years were included. The RR interval (RRi) were recorded during a 10 min period on supine position using a portable heart rate monitor (Polar® H10 model). The data were transferred into Kubios® HRV Standard analysis software and analyzed within the stable sessions containing 256 sequential RRi. RESULTS: The intraclass correlation coefficient (ICC) ranged from 0.942 to 1.000 according to the intrarater analysis by Researcher 01 and 0.915 to 0.998 to the intrarater by Researcher 02. The interrater ICC ranged from 0.921 to 0.998. The coefficient of variation was up to 8.28 for Researcher 01 intrarater analysis, 9.06 for Researcher 02 intrarater analysis and 13.07 for interrater analysis. CONCLUSION: The measurement of HRV using a portable heart rate device in individuals with COPD present acceptable values of intra- and interrater reliability, supporting the use of HRV in the clinical and scientific scenario. Furthermore, it is important that the data analysis be performed by the same experienced evaluator.

Exercise oscillatory ventilation in patients with coexisting chronic obstructive pulmonary disease and heart failure: Clinical implications.

BACKGROUND: Exercise oscillatory ventilation (EOV) is considered an important variable for predicting poor prognosis in patients with heart failure (HF) with reduced left ventricular ejection fraction (HFrEF). However, there are no studies evaluating EOV presence in the coexistence chronic obstructive pulmonary disease (COPD) and HFrEF. AIMS: I) To compare the clinical characteristics of participants with coexisting HFrEF-COPD with and without EOV during cardiopulmonary exercise testing (CPET); and II) to identify the impact of EOV on mortality during follow-up for 35 months. METHODS: 50 stable HFrEF-COPD (EF<50%) participants underwent CPET and were followed for 35 months. The parametric Student's t-test, chi-square tests, linear regression model and Kaplan-Meier analysis were applied. RESULTS: We identified 13 (26%) participants with EOV and 37 (74%) without EOV (N-EOV) during exercise. The EOV group had worse cardiac function (LVEF: 30 ± 6% vs. N-EOV 40 ± 9%, p = 0.007), worse pulmonary function (FEV1: 1.04 ± 0.7 L vs. N-EOV 1.88 ± 0.7 L, p = 0.007), a higher mortality rate [7 (54%) vs. N-EOV 8 (27%), p = 0.02], higher minute ventilation/carbon dioxide production (V̇˙E/ V̇˙ CO2) slope (42 ± 7 vs. N-EOV 36 ± 8, p = 0.04), reduced peak ventilation (L/min) (26.2 ± 16.7 vs. N-EOV 40.3 ± 16.4, p = 0.01) and peak oxygen uptake (mlO2 kg-1 min-1) (11.0 ± 4.0 vs. N-EOV 13.5 ± 3.4 ml●kg-1●min-1, p = 0.04) when compared with N-EOV group. We found that EOV group had a higher risk of mortality during follow-up (long-rank p = 0.001) than patients with N-EOV group. CONCLUSION: The presence of EOV is associated with greater severity of coexisting HFrEF and COPD and a reduced prognosis. Assessment of EOV in participants with coexisting HFrEF-COPD, as a biomarker for both clinical status and prognosis may therefore be warranted.

Non-invasive ventilatory support accelerates the oxygen uptake and heart rate kinetics and improves muscle oxygenation dynamics in COPD-HF patients.

BACKGROUND: The aim of this study was to explore the effects of non-invasive positive pressure ventilation (NIPPV) associated with high-intensity exercise on heart rate (HR) and oxygen uptake (V̇O2) recovery kinetics in in patients with coexistence of chronic obstructive pulmonary disease (COPD) and heart failure (HF). METHODS: This is a randomized, double blinded, sham-controlled study involving 14 HF-COPD patients, who underwent a lung function test and Doppler echocardiography. On two different days, patients performed incremental cardiopulmonary exercise testing (CPET) and two constant-work rate tests (80% of CPET peak) receiving Sham or NIPPV (bilevel mode - Astral 150) in a random order until the limit of tolerance (Tlim). During exercise, oxyhemoglobin and deoxyhemoglobin were assessed using near-infrared spectroscopy (Oxymon, Artinis Medical Systems, Einsteinweg, Netherland). RESULTS: The kinetic variables of both V̇O2 and HR during the high-intensity constant workload protocol were significantly faster in the NIPPV protocol compared to Sham ventilation (P < 0.05). Also, there was a marked improvement in oxygenation and lower deoxygenation of both peripheral and respiratory musculature in TLim during NIPPV when contrasted with Sham ventilation. CONCLUSIONS: NIPPV applied during high-intensity dynamic exercise can effectively improve exercise tolerance, accelerate HR and V̇O2 kinetics, improve respiratory and peripheral muscle oxygenation in COPD-HF patients. These beneficial results from the effects of NIPPV may provide evidence and a basis for high-intensity physical training for these patients in cardiopulmonary rehabilitation programs.

The Effect of Adding Noninvasive Ventilation to High-Intensity Exercise on Peripheral and Respiratory Muscle Oxygenation.

BACKGROUND: We sought to assess whether noninvasive ventilation (NIV) as an adjunct with high-intensity exercise (HIEx) is more effective than exercise alone or exercise + sham on respiratory and peripheral oxygenation and vascular function in subjects with coexisting COPD and heart failure (HF). METHODS: On separate days, subjects performed incremental cardiopulmonary exercise testing and 3 constant load tests: HIEx, HIEx+NIV, and HIEx+sham (bi-level mode, Astral 150). Subjects were randomized with a 1:1 block allocation for the HIEx+NIV group and HIEx+sham group until the limit of tolerance (Tlim). Peripheral and respiratory oxygenation were assessed by oxyhemoglobin (O2Hb) and deoxyhemoglobin (Hb) using near-infrared spectroscopy in the respiratory and peripheral musculature. Vascular function was assessed by endothelial function using the flow-mediated vasodilation (FMD) method. RESULTS: There was a significant increase in FMD (mm), FMD (%), and shear stress in the HIEx+NIV group when compared to HIEx or HIEx+sham (P < .05). Less extraction of O2 (Hb) in the peripheral and respiratory muscles was observed in the HIEx+NIV group (P < .05). We also found correlations between peripheral muscle oxygenation (O2Hb) at the moment 80% of Tlim (r = 0.71, P = .009) and peak of Tlim (100%) (r = 0.76, P = .004) with absolute FMD (mm) immediately after HIEx+NIV. CONCLUSIONS: NIV as an adjunct to HIEx can acutely unload the respiratory musculature with better redistribution of available blood flow and beneficially modulate endothelial function. These results may influence the approach to cardiopulmonary rehabilitation in patients with coexisting COPD-HF.

Right Ventricular Contractile Reserve: A Key Metric to Identifying When Cardiorespiratory Fitness Will Improve With Pulmonary Vasodilators.

Cardiorespiratory fitness (CRF) has been proposed as a vital sign for the past several years, supported by a wealth of evidence demonstrating its significance as a predictor of health trajectory, exercise/functional capacity, and the quality of life. According to the Fick equation, oxygen consumption (VO2) is the product of cardiac output (CO) and arterial-venous oxygen difference, with the former being a primary driver of one's aerobic capacity. In terms of the dependence of aerobic capacity on a robust augmentation of CO from rest to maximal exercise, left ventricular (LV) CO has been the historic focal point. Patients with pulmonary arterial hypertension (PAH) or secondary pulmonary hypertension (PH) present with a significantly compromised CRF; as pathophysiology worsens, so too does CRF. Interventions to improve pulmonary hemodynamics continue to emerge and are now a standard of clinical care in several patient populations with increased pulmonary pressures; new pharmacologic options continue to be explored. Improvement in CRF/aerobic capacity has been and continues to be a primary or leading secondary endpoint in clinical trials examining the effectiveness of pulmonary vasodilators. A central premise for including CRF/aerobic capacity as an endpoint is that pulmonary vasodilation will lead to a significant downstream increase in LV CO and therefore peak VO2. However, the importance of right ventricular (RV) CO to the peak VO2 response continues to be overlooked. The current review provides an overview of relevant principles of exercise physiology, approaches to assessing RV contractile reserve and proposals for clinical trial design and subject phenotyping.

Respiratory and peripheral muscle strength influence recovery of exercise capacity after severe exacerbation of COPD? An observational prospective cohort study.

BACKGROUND: Patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) have decreased exercise tolerance, which may persist for months. In this context, little is known about the associations between muscle strength and recovery of exercise capacity. OBJECTIVE: To assess whether respiratory and peripheral muscle strength influence recovery of exercise capacity in patients hospitalized due to AECOPD. METHODS: Twenty-seven AECOPD patients (aged 69 ± 7 years, 56% male) were included. The following assessments were performed within 24 to 72 h of hospital admission: (i) respiratory muscle strength, measured by maximal inspiratory and expiratory pressures (MIP and MEP); (ii) peripheral muscle strength, assessed by handgrip and quadriceps muscle strength; and (iii) exercise capacity, measured by 6-min walking distance (6MWD). The 6MWD was reassessed 30 days later to determine the recovery of exercise capacity. RESULTS: After 30 days, while 63% of the patients showed clinically important improvement in the 6MWD (recovery ≥ 30 m), 37% showed no change (recovery < 30 m). During hospital stay, the non-recovered group had lower quadriceps muscle strength compared to the recovered group (15 ± 5 vs. 22 ± 6 kgf; P = 0.006), with no significant difference for MIP, MEP and handgrip strength. Only quadriceps muscle strength was associated with recovery of exercise capacity (r = 0.56; P = 0.003). CONCLUSION: AECOPD patients with quadriceps muscle weakness during hospitalization have poor recovery of exercise capacity after 30 days. This finding suggests the importance of early rehabilitation to improve quadriceps strength and accelerate functional recovery after AECOPD.

Obstructive sleep apnea reduces functional capacity and impairs cardiac autonomic modulation during submaximal exercise in patients with chronic obstructive pulmonary disease: A follow-up study.

BACKGROUND: Functional capacity and heart rate variability (HRV) are important prognostic markers in chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea syndrome (OSA). However, the impact of the overlap of these diseases and the one-year clinical follow-up has not yet been evaluated. OBJECTIVES: To assess whether the presence of OSA can impair functional performance and cardiac autonomic control during exercise in patients with COPD; and to verify whether the overlap of these diseases could lead to worse clinical outcomes during the one-year follow-up. METHODS: Thirty-four patients underwent pulmonary function tests, echocardiography and polysomnography for diagnostic confirmation, disease staging, exclusion of any cardiac changes, and allocation between groups. The patients underwent the six-minute walk test (6MWT) to assess functional capacity and HRV during exercise. Subsequently, patients were followed up for 12 months to record outcomes such as exacerbation, hospitalization, and deaths. At the end of this period, the patients were revaluated to verify the hypotheses of the study. RESULTS: The OSA-COPD group showed greater functional impairment when compared to the COPD group (p=0.003) and showed worse cardiac autonomic responses during the 6MWT with greater parasympathetic activation (p=0.03) and less complexity of the autonomic nervous system, in addition to being more likely to exacerbate (p=0.03) during one year of follow-up. CONCLUSION: OSA-COPD produces deleterious effects on functional performance and a greater autonomic imbalance that impairs clinical outcomes.

Is the six-minute step test able to reflect the severity and symptoms based on cat score?

BACKGROUND: This is the first study to investigate the performance of 6MST in COPD patients divided into different symptom severity groups based on the CAT questionnaire score. OBJECTIVES: To evaluate the relationship between the degree symptomatology using the chronic obstructive pulmonary disease (COPD) Assessment Test (CAT) with the six- minute step test (6MST) in COPD patients. METHODS: This is a cross-sectional study in which 59 patients with COPD were evaluated. The groups were stratified according to the subsequent cutoff points: CAT <10 (little impact) n= 22; CAT 11-20 (moderate impact) n=20; CAT <20 (large impact) n=17. During 6MST the individuals were instructed to go up and down a single step with a height of 20 centimeters (cm). RESULTS: Comparing the groups in relation to performance on the 6MST, the number of climbs on the step were significantly higher in the CAT group <10 when compared to the CAT group >20, the variation in HR between rest and peak exercise (∆ HRpeak- rest) was lower in the CAT>20 group compared to the CAT<10 group and the CAT 11- 20 group. We found direct relationships between the number of ascents and descents in the 6MST vs the CAT score (r=0.35, p=0.007); and 6MST vs degree of obstruction of %FEV1 (r-0.46, p=0.002) We verified a linear regression model in which the FEV1 (L) and the CAT score influenced 29% in the performance of the 6MST. CONCLUSION: The COPD severity represented by the FEV1 and the CAT score are associated and influenced by 29% the performance of 6-minute step test. Our findings may have important implications for the clinical evaluation of these patients as well as for rehabilitation.

Exercise modulates the immune system in cardiorespiratory disease patients: Implications for clinical practice during the COVID-19 pandemic.

BACKGROUND: Patients with cardiorespiratory problems often suffer from systemic inflammation. Stress due to the disease and continuous inflammation can undermine the success of the rehabilitation program. OBJECTIVE: This review has been undertaken primarily to understand the effectiveness of exercise training on the immune system in individuals undergoing cardiorespiratory rehabilitation and its implications for further management during the COVID-19 pandemic. METHODS: Assessors analyzed related studies identified in the MEDLINE, PROQUEST, PUBMED, Cochrane Library, CINAHL, EMBASE, Google Scholar, Physiotherapy Evidence, and Science Direct databases. The studies were divided into groups focused on the effect of exercise on blood leukocytes, the anti-inflammatory effect, and the role of nutrition and exercise in resolving inflammation. RESULTS: Twenty-eight studies were included in this review. The number of studies included in each section was as follows: the effects of exercise training on leukocytes in cardiorespiratory conditions (n = 8), anti-inflammatory effect (n = 6), and the role of nutrition and exercise in resolving inflammation (n = 14). The bias risk assessment showed poor internal validity; most included studies were assigned no and unclear descriptors. CONCLUSIONS: Substantive evidence is presented that emphasizes the role of moderate-intensity exercise in boosting the immune system in patients with cardiorespiratory diseases. Exercise has anti-inflammatory effects that are vital for overall well-being and resolving longstanding inflammation. Individuals with an active lifestyle had a better pathogen immune response than more sedentary individuals. Our findings highlight the current need to investigate the long-term effects of cardiorespiratory rehabilitation programs.