Revista Portuguesa de Pneumologia (May 2006)
O trabalho de caminhada dos seis minutos não se correlaciona com o grau de obstrução do fluxo aéreo em doentes portadores de Doença Pulmonar Obstrutiva Crónica (DPOC) Six-minute walk work is not correlated to the degree of airflow obstruction in patients with Chronic Obstructive Pulmonary Disease (COPD)
Abstract
Introdução: No teste de caminhada dos seis minutos, o principal parâmetro é a distância percorrida. Não se considera o peso corporal, embora se conheça a sua influência na capacidade de exercício. Por outro lado, existem evidências de que o grau de obstrução não se correlaciona com a distância caminhada. Objectivo: Verificar se existe correlação entre o grau de obstrução do fluxo aéreo e o trabalho de caminhar obtido a partir do produto distância x x peso (DxP). Materiais e métodos: Foram estudados 60 doentes portadores de doença pulmonar obstrutiva crónica. As variáveis fisiológicas e funcionais foram correlacionadas com a distância percorrida e com o produto distância/peso. Resultados: Não se encontraram correlações entre o trabalho de caminhar e o grau de obstrução ao fluxo aéreo, nem com os volumes pulmonares. Encontrou-se correlação positiva e significativa da distância com a difusão de monóxido de carbono (DLCO) (r=0,6; pIntroduction: The six-minute walking test distance, despite being considered the main parameter, does not consider body weight which is known to influence exercise capacity. A body of evidence shows the degree of airflow obstruction does not correlate to walking distance and the body weight affects the work/energy required to perform the walk. Objective: To verify if the degree of airflow obstruction correlates to six-minute walk work obtained by weight - walking distance product. Patient and methods: A total of 60 patients with chronic obstructive pulmonary disease were evaluated. The physiological and functional variables were correlated to distance and body weight - walking distance product (WxW). Results: There were no correlations between six-minute walk work and the degree of airflow obstruction. A positive and significant correlation were observed between the distance and Carbon Monoxide Diffusing Capacity (DLCO) (r=0.6; p<0.01) and between the distance and final SatO 2 (r= 0.3 ; p <0.05). Correlation between distance and Borg scale was negative and significant (r= -0.3; p<0.05). The six-minute walk work was positive and significantly correlated to DLCO (r= 0.7; p<0.01) and negative but significantly correlated to Borg scale in the initial (r= - 0.3; p<0.01) and final of the test (r= -0.4; p<0.05). Conclusion: Based on this data, there was no correlation between the degree of airflow obstruction and six-minute walk work test. The DLCO was the only respiratory functional parameter significantly correlated to the distance and to the six-minute walk work.
