The BODE Index After Lung Volume Reduction Surgery Correlates With Survival

Abstract

A recently introduced, multidimensional index called BODE (body mass index [BMI], degree of airflow obstruction assessed by spirometry, grade of dyspnea, and exercise capacity), quantified by 6-min walking distance (6MWD), has excellent predictive power with respect to outcome in COPD. We investigated whether the BODE index is able to predict survival after lung volume reduction surgery (LVRS). Retrospective study. Tertiary university hospital. One hundred eight-six COPD patients (76 women) with severe emphysema (mean +/- SD age, 64 +/- 8 years; mean FEV(1), 28 +/- 8% of predicted). Bilateral thoracoscopic LVRS. BMI, pulmonary function, 6MWD, and the modified Medical Research Council dyspnea score were assessed before and 3 months after LVRS, and the BODE index was calculated. The patients were followed up with respect to survival for a median time of 40 months (range, 3 to 116 months) after surgery. The mean BODE index decreased from 7.2 +/- 1.6 preoperatively to 4.0 +/- 2.0 at 3 months after LVRS (p < 0.001). The postoperative but not the preoperative BODE correlated with survival, although preoperative patient characteristics were comparable between short-term (< 5 years) and long-term (> 5 years) survivors. A decrease to a lower BODE score class was associated with a reduced mortality (hazard ratio, 0.497, 95% confidence interval, 0.375 to 0.659; p < 0.001). The C statistic for the ability of the BODE index to predict the risk of death was larger (0.74) than that for the FEV(1) (0.63), the degree of dyspnea (0.64), or the 6MWD (0.62). The postoperative BODE index is a powerful predictor of survival in COPD patients after LVRS.