Prognostic utility of the 2011 GOLD classification and other multidimensional tools in Asian COPD patients: a prospective cohort study

BACKGROUND: How well the 2011 Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification prognosticates for Asian patients with COPD is unknown. OBJECTIVE: The authors aimed to study the predictive utility of the GOLD 2011 classification for exacerbations and mortality as compared with other multidimensional tools in an Asian population. METHODS: In all, 1,110 COPD patients were prospectively followed between March 2008 and March 2013. They were classified using the 2011 and 2007 GOLD guidelines, modified Medical Research Council score, St. George’s Respiratory Questionnaire (SGRQ), and Body mass index, Obstruction, Dyspnea (BOD) index. Outcome measures were exacerbations and mortality. Multivariable survival analyses and receiver operating characteristic (ROC) curves were used to assess the different classification systems. RESULTS: Time-to-event analyses demonstrated earlier exacerbations in 2011’s GOLD D when compared with GOLD A (hazard ratio [HR] 0.54, 95% confidence interval [CI]: 0.31–0.95, P=0.032) and GOLD B (HR 0.62, 95% CI: 0.45–0.85, P=0.003) and higher mortality when compared with GOLD A (HR 0.37, 95% CI: 0.16–0.88, P=0.025) and GOLD B (HR 0.46, 95% CI: 0.31–0.70, P<0.001). The areas under the ROC curve for GOLD 2011, GOLD 2007, modified Medical Research Council, St. George’s Respiratory Questionnaire, and BOD index were 0.62, 0.59, 0.61, 0.60, and 0.61, respectively, for the prediction of exacerbations and 0.71, 0.70, 0.71, 0.71, and 0.72, respectively, for the prediction of mortality (ROC comparator, P>0.05). CONCLUSION: The 2011 GOLD classification predicts exacerbations and mortality moderately well in Asian COPD patients. Its prognostic utility is similar to that of other multidimensional systems.