OBJECTIVES

: We analyzed the development of disease-specific and generic health-related quality of life (HRQL) over three years in a large cohort of COPD patients and identified factors associated with deterioration.

METHODS

: Three years after baseline, 1182 participants of the German COPD cohort COSYCONET were re-examined and completed the disease-specific Saint George´s Respiratory Questionnaire (SGRQ), which consists of three components (activity, impacts, symptoms) summarized in a total score, and the generic EQ-5D Visual Analog Scale (EQ VAS). Logistic regression models were used to determine predictors for clinically relevant HRQL deterioration (using established MCIDs) considering baseline information on COPD GOLD grade, age, sex, BMI, education, smoking status, comorbidity burden, symptoms, and exacerbation history. Inverse Probability Weights were included to account for dropout bias.

RESULTS

: The majority of patients were male (61%) with a mean age of 64 years and FEV₁ %predicted 56%. Mean FEV₁ declined by 150 ml over three years. During the same period, disease-specific HRQL significantly deteriorated as indicated by an increase in 1.3 units in SGRQ total score. This deterioration was completely driven by the activity component (+4 units). The generic EQ VAS remained unchanged. A clinically relevant worsening of SGRQ/EQ VAS was observed for 39% and 35% of patients, respectively. Regarding the disease-specific SGRQ, patients with baseline GOLD grade 2, 3 or 4 had a significantly higher risk of deterioration compared to grade 1 (OR=1.5, OR=2.5, OR=2.8 respectively). Furthermore, underweight (OR=1.7), the presence of sputum (OR=1.7) or dyspnea (OR=1.5) and active smoking (OR=1.6, ref. never smoker) were identified as predictors for deterioration. These factors were also significant predictors when using the EQ VAS, except smoking and underweight.

CONCLUSIONS

: Knowledge about factors predicting changes in HRQL may help to identify subgroups of patients with special needs for disease management.