Relationship between BODE index, quality of life and inflammatory cytokines in COPD patients
Background and aims: Recently a multidimensional grading system based on the body mass index (B), degree of airflow obstruction (O), dyspnea (D) and exercise capacity (E) - the BODE index - has begun to be used increasingly for the evaluation of chronic obstructive pulmonary disease (COPD) patients. The aim of our study was to investigate the relation- ship between the BODE index and disease duration, annual exacerbation and hospitalization rates, health related quality of life and systemic inflammatory markers like C-reactive protein (CRP), tumor necrosis factor (TNF)-α and interleukin (IL)-8. Materials and methods: In 88 stable COPD patients we evalu- ated the body-mass index, pulmonary function tests, Modified Medical Research Council dyspnea scale and six- minute walk test (6MWT). BODE scores were determined. Disease duration, number of exacerbations and hospitaliza- tion in the previous year were recorded. We also performed arterial blood gases analysis, administered the St. George’s Respiratory Questionnaire (SGRQ) and measured serum lev- els of CRP, TNF-α, IL-8. Results: According to BODE score 52% of patients were BODE 1, 21% BODE 2, 15% BODE 3 and 12% were BODE 4. There was a significant relationship between BODE index and COPD stage as classified according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) (p < 0.001). Correlations between BODE score and disease duration (p = 0.011), number of exacerbations (p < 0.001) and hospitaliza- tions (p < 0.001) in the last year were also observed. SGRQ symptom, activity, emotion scores and total scores were found to be significantly correlated to BODE (p < 0.001). Serum CRP levels and BODE were also correlated (p = 0.014); however, no correlation was found between serum levels of TNF-α and IL-8 and BODE. Conclusions: As the BODE index shows a strong correlation with various prognostic and follow up parameters of COPD and systemic inflammation, its use should be considered for the evaluation of COPD patients.