Concurrent validity between field tests and cardiopulmonary exercise testing in patients with idiopathic pulmonary fibrosis.

BACKGROUND: Maximal treadmill cardiopulmonary exercise testing is the gold standard for assessing functional capacity in patients with idiopathic pulmonary fibrosis (IPF). PURPOSE: Primarily to investigate the concurrent validity between three field tests and cardiopulmonary exercise testing in these patients. METHODS: Patients performed the cardiopulmonary exercise testing, a six-minute walk test, an incremental shuttle walk test, and, the Glittre-ADL test. For cardiopulmonary exercise testing, the ten seconds with the higher average of the peak oxygen uptake obtained within the last 30 seconds were considered; for six-minute walk test and incremental shuttle walk test, the longer distance; and for the Glittre-ADL test, the shorter time spent. Concurrent validity was assessed using different regression models based on the best adjustment of the data. RESULTS: Twenty-two patients with IPF were assessed, aged: 68 ± 8.1 years, 13 male. Patients presented a peak oxygen uptake of 16.5 ± 3.6 mL.kg-1.min1, achieving a distance of 512.6 ± 102.8 meters in the six-minute walk test and 415.7 ± 125.1 meters in incremental shuttle walk test. The walking distance in the six-minute walk test and the incremental shuttle walk test explained, respectively, 64% and 56% peak oxygen uptake variance observed in the cardiopulmonary exercise testing (R2 = 0.64,p < .001; R2 = 0.56,p < .001). The time spent in the Glittre-ADL test was 233.4 ± 88.7 seconds and explained 47% of the peak oxygen uptake variance observed in cardiopulmonary exercise testing (R2 = 0.47,p = .001). CONCLUSION: The six-minute walk test, incremental shuttle walk test, and Glittre-ADL test were considered valid tests to explain the peak oxygen uptake variance obtained by the cardiopulmonary exercise testing in patients with IPF.

Perception of patients with interstitial lung diseases submitted to inspiratory muscle training.

BACKGROUND: Although inspiratory muscle training reduces dyspnea in patients with chronic respiratory diseases, it was not yet evaluated in a sample composed exclusively of patients with interstitial lung diseases. OBJECTIVE: To discuss the perception of patients with interstitial lung diseases about inspiratory muscle training intervention. METHODS: This is a qualitative study. Data were collected using semi-structured interviews, transcribed, and analyzed by thematic analysis. RESULTS: Fourteen patients (64 ± 7 years) with interstitial lung disease were interviewed. Average participation in the inspiratory muscle training program was 90% (range, 66-100%). Three themes were elaborated: 1) dyspnea and other symptoms in daily life (e.g. "I could not carry out a bag; I was very uncomfortable"); 2) less symptom and greater performance (e.g. "I wash and change my clothes, house cleaning, do everything without feeling anything"); and 3) IMT: a time dedicated to my health (e.g. "For me it was great because I saw my evolution every day"). CONCLUSION: Patients noticed improvements in symptoms and performance related to daily activities. Despite initial difficulties, patients continued training as planned.

Test-retest reliability and concurrent validity of a digital manovacuometer / La reproducibilidad de test-retest y la validez concurrente del manovacuometro digital / Reprodutibilidade teste-reteste e validade concorrente de manovacuômetro digital

The manovacuometer is a simple, quick and non-invasive test which measures the maximal respiratory pressures (MRS). Guidelines recommend the use of a digital manovacuometer due to its high accuracy. The purpose of this study was to assess the test-retest reliability and concurrent validity of a digital manovacuometer in measuring the maximal inspiratory and expiratory pressures (MIP/MEP) and nasal inspiratory pressure while sniffing (SNIP). A total of 30 healthy subjects were assessed (20-30 years old) using the UFMG and MicroRPM(r) (Micro Medical, UK) digital manovacuometers. To assess reliability, Intraclass Correlation Coefficient (ICC) and Student's t test it was used for dependent samples. For the validity assessment, the following were used: Pearson correlation, Student's t test for dependent samples, linear regression and the Bland-Altman method. The level of significance was set at 5% (p<0.05). The ICC values were significant and showed a good magnitude (0.76 to 0.89) and no significant differences were found between the means of the variables of the UFMG digital manovacuometer analyzed within two days (p>0.05); the correlation between observed values from the two instruments was of high magnitude for all variables (0.82 to 0.85); no significant difference was found between the values obtained for both instruments (p>0.05); a strong association was observed between measures of MIP and MEP obtained by the two methods and Bland-Altman analysis showed no systematic overestimation or underestimation of maximal respiratory pressures and SNIP. In conclusion, the results suggest that the UFMG manovacuometer is a reliable and valid instrument for assessing MIP, MEP and SNIP in healthy subjects.

La manovacuometría es una prueba sencilla, rápida y no invasiva que mide las presiones respiratorias máximas (PRM). Directrices recomiendan el uso del manuvacuómetro digital debido a su alta precisión. El objetivo de este estudio fue evaluar la reproducibilidad test-retest y la validez concurrente de un manuvacuómetro digital para medir las presiones inspiratoria y espiratoria máximas (PImáx y PEmáx) y de la presión inspiratoria nasal durante la aspiración (SNIP). Se evaluaron 30 sujetos sanos (20-30 años) por medio de los manovacuómetros digitales UFMG y MicroRPM(r) (Micro Medical, UK). Para evaluar la reproducibilidad, se utilizó el coeficiente de correlación intraclase (CCI) y el test t de student para muestras dependientes. Para el análisis de la validez se utilizaron: la correlación de Pearson, el test t de student para muestras dependientes, el análisis de regresión lineal y el método Bland-Altman. El nivel de significación considerado fue del 5% (p<0,05). Los valores de CCI fueron significativos y de buena magnitud (0,76 a 0,89) y no se encontraron diferencias significativas entre las medias de las variables del manovacuómetro UFMG analizadas en los dos días (p>0,05). La correlación entre los valores observados en los dos instrumentos fue de alta magnitud para todas las variables (0,82 a 0,85); no hubo diferencia significativa entre los valores medios obtenidos en los dos instrumentos (p>0,05); Se observó una fuerte asociación entre las medidas de las PRM obtenidas por los dos métodos y el análisis de Bland-Altman no demostró sobreestimación o subestimación sistemática de las PRM y del SNIP. En conclusión, los resultados sugieren que el manovacuómetro UFMG es fiable y válido para la evaluación de las PRM y SNIP en sujetos sanos.

A manovacuometria é um teste simples, rápido e não invasivo que mensura as pressões respiratórias máximas (PRM). Diretrizes recomendam o uso do manovacuômetro digital devido à sua alta precisão. O objetivo deste estudo foi avaliar a reprodutibilidade teste-reteste e a validade concorrente de um manovacuômetro digital na mensuração das pressões inspiratórias e expiratórias máximas (PImáx e PEmáx) e da pressão inspiratória nasal durante o fungar (SNIP). Foram avaliados 30 indivíduos saudáveis (20-30 anos) utilizando os manovacuômetros digitais UFMG e MicroRPM(r) (Micro Medical, UK). Para avaliar a reprodutibilidade, foi utilizado o Coeficiente de Correlação Intraclasse (CCI) e teste t de student para amostras dependentes. Para análise da validade foram utilizados: a correlação de Pearson, o teste t de student para amostras dependentes, a análise de regressão linear e o método Bland-Altman. O nível de significância considerado foi de 5% (p<0,05). Os valores de CCI foram significativos e de boa magnitude (0,76 a 0,89) e não foram encontradas diferenças significativas entre as médias das variáveis do manovacuômetro UFMG analisadas nos dois dias (p>0,05). A correlação entre os valores observados nos dois instrumentos foi de alta magnitude para todas as variáveis (0,82 a 0,85); não houve diferença significativa entre os valores médios obtidos nos dois instrumentos (p>0,05); foi observada forte associação entre as medidas das PRM obtidas pelos dois métodos e a análise de Bland-Altman não demonstrou superestimação ou subestimação sistemática das PRM e do SNIP. Em conclusão, os resultados sugerem que o manovacuômetro UFMG é confiável e válido para avaliação das PRM e SNIP em indivíduos saudáveis.