Quality of life in patients with chronic obstructive pulmonary disease: the predictive validity of the BODE index

Background: Chronic obstructive pulmonary disease (COPD) is currently the fourth cause of mortality and morbility in the developed world. Patients with COPD experience a progressive deterioration of health-related quality of life (HRQOL). A new model of severity classification, the body mass index, bronchial obstruction, dyspnoea, exercise (BODE) index, has recently been proposed. Objective: To evaluate the relationship between HRQOL and the BODE index, and the predictive ability of BODE on HRQOL measurements. Methods: Two HRQOL questionnaires were administered, namely the Nottingham Health Profile (NHP) and St George's Respiratory Questionnaire (SGRQ), in a sample of 67 patients with severe COPD. Results: Pearsonś correlation coefficient analysis shows a positive correlation between the BODE index and the total scores of the specific ( P < 0.001), and general HRQOL ( P < 0.001); the analysis shows a significant correlation between the BODE index and the subscales of symptoms, activity and impact of SGRQ ( P < 0.001) and the subscales energy and physical mobility of the NHP ( P < 0.001). The regression analysis shows that the BODE index is a significant predictor of HRQOL, explaining 46,1% of the total score of the SGRQ ( P < 0.001) and 14.8% of the total score of the NHP ( P < 0.001). Conclusions: The BODE index is good at predicting the worsening of HRQOL in patients with severe COPD. Chronic Respiratory Disease 2008; 5: 7—11