Use of six-minute walking test to predict peak oxygen consumption in pulmonary vascular disease.

In recent years, exercise capacity has received increasing attention due to its use as a prognostic tool and its association with functional status in patients with pulmonary vascular diseases. For this reason, both distance walked in the 6‐min walking test (6MWD) and VO2peak are included in the risk assessment table of the current clinical guidelines for PH. However, despite the validity of both tests, the CPET is the gold standard examination for assessing exercise capacity, even though it is an expensive test that requires a skilled operator and specialized equipment with limited availability

Biological Activity of NHC-Gold-Alkynyl Complexes Derived from 3-Hydroxyflavones

In this paper we describe the synthesis of new N-heterocyclic carbene (NHC) gold(I) derivatives with flavone-derived ligands with a propargyl ether group. The compounds were screened for their antimicrobial and anticancer activities, showing greater activity against bacteria than against colon cancer cells (Caco-2). Complexes [Au(L2b)(IMe)] (1b) and [Au(L2b)(IPr)] (2b) were found to be active against both Gram-positive and Gram-negative strains. The mechanism of action of 1b was evaluated by measurement of thioredoxin reductase (TrxR) and dihydrofolate reductase (DHFR) activity, besides scanning electron microscopy (SEM). Inhibition of the enzyme thioredoxin reductase is not observed in either Escherichia Coli or Caco-2 cells; however, DHFR activity is compromised after incubation of E. coli cells with complex 1b. Moreover, loss of structural integrity and change in bacterial shape is observed in the images obtained from scanning electron microscopy (SEM) after treatment E. coli cells with complex 1b

Validity of instruments to measure physical activity may be questionable due to a lack of conceptual frameworks: a systematic review

BACKGROUND: Regulators' guidance documents for the development and validation of patient reported outcomes (PROs) advise the use of conceptual frameworks, which outline the structure of the concept that a PRO aims to measure. It is unknown if currently available PROs are based on conceptual frameworks. This study, limited to a specific case, aimed (i) to identify conceptual frameworks of physical activity in chronic respiratory patients or similar populations (chronic heart disease patients or the elderly), and (ii) to assess if the development and validation of PROs to measure physical activity in these populations were based on a conceptual framework of physical activity. METHODS: Two systematic reviews were conducted through search in Medline, Embase, Psychinfo, and Cinahl databases up to January 2010. RESULTS: In the first review only 2 references, identified from 581 references about physical activity in the defined populations, provided a conceptual framework of physical activity in COPD patients. In the second review, out of 103 studies developing PROs to measure physical activity or related constructs, none of them was based on a conceptual framework of physical activity. CONCLUSIONS: These findings raise concerns about how the large body of evidence from studies that use physical activity PRO instruments should be evaluated by health care providers, guideline developers, and regulatory bodies

Effect of pulmonary hypertension on exercise tolerance in patients with COPD: a prognostic systematic review and meta-analysis

Background: Pulmonary hypertension (PH) is a frequent complication in patients with COPD. Objective: To determine if, in patients with COPD, the presence of PH decreases exercise tolerance. Methods: We included studies that analysed exercise tolerance using a cardiopulmonary exercise test (CPET) in patients with COPD with PH (COPD-PH) and without PH (COPD-nonPH). Two independent reviewers analysed the studies, extracted the data and assessed the quality of the evidence. Results: Of the 4915 articles initially identified, seven reported 257 patients with COPD-PH and 404 patients with COPD-nonPH. The COPD-PH group showed differences in peak oxygen consumption (V'O2peak ), -3.09 mL·kg-1·min-1 (95% CI -4.74 to -1.43, p=0.0003); maximum workload (Wmax), -20.5 W (95% CI -34.4 to -6.5, p=0.004); and oxygen pulse (O2 pulse), -1.24 mL·beat-1 (95% CI -2.40 to -0.09, p=0.03), in comparison to the group with COPD-nonPH. If we excluded studies with lung transplant candidates, the sensitivity analyses showed even bigger differences: V'O2 , -4.26 mL·min-1·kg-1 (95% CI -5.50 to -3.02 mL·kg-1·min-1, p<0.00001); Wmax, -26.6 W (95% CI -32.1 to -21.1 W, p<0.00001); and O2 pulse, -2.04 mL·beat-1 (95% CI -2.92 to -1.15 mL·beat-1, p<0.0001). Conclusion: Exercise tolerance was significantly lower in patients with COPD-PH than in patients with COPD-nonPH, particularly in nontransplant candidates

Assessment of Exercise Capacity in Post-COVID-19 Patients: How Is the Appropriate Test Chosen?

There is a wide range of sequelae affecting COVID-19 survivors, including impaired physical capacity. These sequelae can affect the quality of life and return to work of the active population. Therefore, one of the pillars of following-up is the evaluation of physical capacity, which can be assessed with field tests (such as the six-minute walk test, the one-minute standing test, the Chester step test, and the shuttle walking test) or laboratory tests (such as the cardiopulmonary exercise test). These tests can be performed in different contexts and have amply demonstrated their usefulness in the assessment of physical capacity both in post-COVID-19 patients and in other chronic respiratory, metabolic, cardiologic, or neurologic diseases. However, when traditional tests cannot be performed, physical function can be a good substitute, especially for assessing the effects of an intervention. For example, the Short Physical Performance Battery assessment and the Timed Up and Go assessment are widely accepted in older adults. Thus, the test should be chosen according to the characteristics of each subject

Physical Activity Characteristics across GOLD Quadrants Depend on the Questionnaire Used

BACKGROUND:The GOLD multidimensional classification of COPD severity combines the exacerbation risk with the symptom experience, for which 3 different questionnaires are permitted. This study investigated differences in physical activity (PA) in the different GOLD quadrants and patient's distribution in relation to the questionnaire used. METHODS:136 COPD patients (58±21% FEV1 predicted, 34F/102M) completed COPD assessment test (CAT), clinical COPD questionnaire (CCQ) and modified Medical Research Council (mMRC) questionnaire. Exacerbation history, spirometry and 6MWD were collected. PA was objectively measured for 2 periods of 1 week, 6 months apart, in 5 European centres; to minimise seasonal and clinical variation the average of these two periods was used for analysis. RESULTS:GOLD quadrants C+D had reduced PA compared with A+B (3824 [2976] vs. 5508 [4671] steps.d-1, p<0.0001). The choice of questionnaire yielded different patient distributions (agreement mMRC-CAT κ = 0.57; CCQ-mMRC κ = 0.71; CCQ-CAT κ = 0.72) with different clinical characteristics. PA was notably lower in patients with an mMRC score ≥2 (3430 [2537] vs. 5443 [3776] steps.d-1, p <0.001) in both the low and high risk quadrants. CONCLUSIONS:Using different questionnaires changes the patient distribution and results in different clinical characteristics. Therefore, standardization of the questionnaire used for classification is critical to allow comparison of different studies using this as an entry criterion. CLINICAL TRIAL REGISTRATION:ClinicalTrials.gov NCT01388218

Use of automatic 6-minute walking test recording system in patients with chronic respiratory diseases

To the editor: Physical capacity tests are used for the diagnosis, prognosis and monitoring of chronic respiratory diseases (CRD), such as Chronic Obstructive Pulmonary Disease (COPD) or Pulmonary Hypertension (PH).1 Among these tests, the most widely used is the 6-minute walking test (6MWT).2 Additionally, the guidelines highlight the need to continuously record biological signals, particularly oxygen saturation (SpO2), which has been shown to be a prognostic marker in CRD.2 [...]The study was supported by grants from Societat Catalana de Pneumologia (SOCAP) (ESTEVE TEIJIN/2021), PI17/1515 and PI21/0555 from the Instituto de Salud Carlos III (ISCiii), co-funded by the European Union (ERDF/ESF, ”A way to make Europe” “Investing in your future”) and Premi d’Innovació de l’Hospital Clínic de Barcelona (2021). For UPC authors this work has been supported by the Spanish Ministry of Science and Innovation under contract PID2021-124463OB-I00, the Catalan Government under contract 2021 SGR 00326 and the Catalan Department of Research and Universities.Peer ReviewedPostprint (published version

Efectos de la hipertensión pulmonar en la capacidad de ejercicio en pacientes con enfermedad pulmonar obstructiva crónica

Introduction: The impact of pulmonary hypertension (PH) on exercise tolerance in chronic obstructive pulmonary disease (COPD) has not been fully elucidated. It is necessary to characterize pulmonary hemodynamics in patients with moderate to severe COPD in order to improve their management. The aim of the study was to determine whether in COPD the presence of PH is associated with reduced exercise tolerance in a cohort of stable COPD patients. Methods: Cross-sectional analysis of 174 COPD patients clinically stable: 109 without PH and 65 with PH (COPD-PH). We assessed socio-demographic data, lung function, quality of life, dyspnea, cardiopulmonary exercise testing (CPET), constant workload endurance time (CWET), and six-minute walk test (6MWT). We elaborated a logistic regression model to explore the impact of PH on exercise capacity in COPD patients. Results: COPD-PH patients showed lower exercise capacity both at maximal (CPET) (43(20) versus 68(27) Watts and 50(19)% versus 71(18)% predicted peak oxygen consumption (VO2peak), COPD-PH and COPD, respectively), and at submaximal tests (6MWT) (382(94) versus 486(95) m). In addition, the COPD-PH group had lower endurance time than the non-PH COPD group (265(113) s and 295(164) s, respectively). Conclusions: The presence of PH is an independent factor that impairs exercise capacity in COPD. SPANISH Introducción: El impacto de la hipertensión pulmonar (HTP) en la tolerancia al ejercicio en la enfermedad pulmonar obstructiva crónica (EPOC) no se ha dilucidado en su totalidad. Es necesario caracterizar la hemodinámica pulmonar de los pacientes con EPOC moderada a grave para poder mejorar su manejo. El objetivo de este estudio fue determinar si la presencia de HTP en la EPOC se asociaba con una disminución en la tolerancia al ejercicio en una cohorte de pacientes con EPOC estable. Métodos: Estudio transversal de 174 pacientes con EPOC clínicamente estables: 109 de ellos no mostraban HTP y 65 de ellos sí (EPOC-HTP). Valoramos la información sociodemográfica, la función pulmonar, la calidad de vida, la disnea, realizamos una prueba de ejercicio cardiopulmonar (PECP), medimos el tiempo de tolerancia de ejercicio constante y realizamos de marcha de seis minutos (6MWT, por sus siglas en inglés). Elaboramos un modelo de regresión logística para explorar el impacto de la HTP en la capacidad de ejercicio de los pacientes con EPOC. Resultados: Los pacientes con EPOC-HTP mostraron una menor capacidad de ejercicio, tanto en las pruebas máximas (PECP) (43 (20) W frente a 68 (27) W y 50 (19)% frente a 71 (18)% de consumo de oxígeno máximo predicho (VO2 max), para pacientes con EPOC-HTP y pacientes con EPOC, respectivamente) como en las pruebas submáximas (6MWT) (382 (94) m frente a 486 (95) m). Además, el grupo de EPOC-HTP presentó un menor tiempo de resistencia que el grupo de EPOC sin HTP (265 (113) s y 295 (164) s, respectivamente). Conclusiones: La presencia de HTP es un factor independiente que afecta a la capacidad de ejercicio en la EPOC

Correction: Can health status questionnaires be used as a measure of physical activity in COPD patients? (vol 47, pg 1565, 2016)

This article from the March 2015 issue of the European Respiratory Journal was published with an error in the author list. The third author, Corina De Jong, was incorrectly listed as Corina De Jongh. The article has been corrected and republished online

Socio-environmental correlates of physical activity in patients with chronic obstructive pulmonary disease (COPD)

BACKGROUND: Study of the causes of the reduced levels of physical activity in patients with COPD has been scarce and limited to biological factors. AIM: To assess the relationship between novel socio-environmental factors, namely dog walking, grandparenting, neighbourhood deprivation, residential surrounding greenness and residential proximity to green or blue spaces, and amount and intensity of physical activity in COPD patients. METHODS: This cross-sectional study recruited 410 COPD patients from five Catalan municipalities. Dog walking and grandparenting were assessed by questionnaire. Neighbourhood deprivation was assessed using the census Urban Vulnerability Index, residential surrounding greenness by the satellite-derived Normalized Difference Vegetation Index, and residential proximity to green or blue spaces as living within 300 m of such a space. Physical activity was measured during 1 week by accelerometer to assess time spent on moderate-to-vigorous physical activity (MVPA) and vector magnitude units (VMU) per minute. FINDINGS: Patients were 85% male, had a mean (SD) age of 69 (9) years, and post-bronchodilator FEV1 of 56 (17) %pred. After adjusting for age, sex, socio-economic status, dyspnoea, exercise capacity and anxiety in a linear regression model, both dog walking and grandparenting were significantly associated with an increase both in time in MVPA (18 min/day (p<0.01) and 9 min/day (p<0.05), respectively) and in physical activity intensity (76 VMU/min (p=0.05) and 59 VMUs/min (p<0.05), respectively). Neighbourhood deprivation, surrounding greenness and proximity to green or blue spaces were not associated with physical activity. CONCLUSIONS: Dog walking and grandparenting are associated with a higher amount and intensity of physical activity in COPD patients. TRIAL REGISTRATION NUMBER: Pre-results, NCT01897298