Health status measured with the CRQ does not predict mortality in COPD.

Abstract

One purpose of measuring health status is to predict future outcomes. The aim of this study was to investigate the ability of health status derived from the Chronic Respiratory Disease Questionnaire (CRQ) to predict mortality in chronic obstructive pulmonary disease (COPD). One-hundred and forty-three patients with COPD were recruited. Health status, using the CRQ, and pulmonary function were measured at entry. Mortality after 7 yrs was then assessed. Univariate and multivariate Cox proportional hazards analyses were performed to predict those factors related to mortality. Of all the patients, 13 could not be followed up and 40 had died. The survival rate was 69% at 7 yrs. Univariate regression analyses revealed that the dyspnoea and emotional function domains and the total score of the CRQ were weakly but significantly correlated with mortality from all causes. However, multivariate regression analyses revealed that age and forced expiratory volume in one second were the strongest predictors of mortality, and health status was not a significant factor. Although there was a weak but significant relationship between health status and subsequent mortality in chronic obstructive pulmonary disease, it was not significant after an adjustment for age and pulmonary function. Mortality cannot be predicted from Chronic Respiratory Disease Questionnaire scores.