Survival characteristics and predictors of mortality in COPD subjects

Abstract

<b>Background:</b> COPD is the fourth leading cause of mortality worldwide. <b>Objective:</b> To determine the predictors of mortality in COPD subjects and the difference between clinical characteristics between survivor and non-survivor subjects. <b>Methods:</b> One-year prospective cohort study of 120 COPD subjects was conducted. Sociodemographic, clinical variables and quality of life measured by Saint George’s Respiratory Questionnaire(SGRQ) and Short-Form 36 physical and mental scale(PCS SF-36, MCS SF 36) were included. Logistic and Cox regression models were used to assess the influence of these variables on mortality. <b>Results:</b> After 1 year of follow-up, 15(12.5%) subjects had died of which 53.3% were due to COPD exacerbation . A greater percentage of the non-survivor subjects were women. No difference was found between survivor and non-survivor subjects in terms of age group, sex, education, smoking habits, SGRQ and depression. However, significant difference was predicted in SF 36, FEV1(Litres), GOLD scale, BODE Index, Comorbidity Index and BMI. PCS SF36 (OR 0.852; 95% CI, 0.67–1.08; p=0.014), MCS SF36 (OR 1.06; 95% CI, 0.93–1.22; p=0.048), Age (OR 1.077; 95% CI, 0.94–1.23; p=0.036) and previous hospitalization (OR 264.93; 95% CI, 4.781–14829; p=0.001) proved to be associated with mortality in logistic regression analysis. Age, FEV1, BODE and CAT Score were also linked to mortality in the model. BMI, sex, depression and SGRQ did not correlate with mortality. <b>Conclusions:</b> Previous hospitalization in 1 year (AUC=0.846) and Length of stay (AUC=0.823) occupied first and second place as mortality predictors, followed by FEV1(L), BODE Index, PCS SF36. So early recognition of these predictors should be considered by treating physician.