F-133 Symptom variability associates with rapid decline of lung function in COPD patients

Purpose: While the symptom variability is an important characteristic in asthma patients, symptoms in COPD patients are thought to have little variability. However, significant portion of COPD patients perceived variability in their symptoms. Symptom variability impacts on daily life activity and may be associated with exacerbation. However, there is no report investigating the impact of symptom variability on the natural course of COPD. Methods: We analyzed the data of COPD patients in the Korean Obstructive Lung Disease (KOLD) cohort who had been followed longer than 1 year. Symptom scores of annually checked SGRQ were used and symptom variability was defined as standard deviation (SD) of SGRQ score 3. Patients were divided into two groups according to the presence or absence of symptom variability. Baseline and long-term clinical characteristics were compared between two groups. Results: Among 347 patients, 191 patients were classified as COPD with symptom variability and 156 patients were as COPD without symptom variability. Baseline characteristics in terms of age, smoking history, FEV1, blood eosinophil (%), comorbidity, the proportion of patients with chronic bronchitis symptoms were not different between two groups. In addition, frequency of exacerbations did not differ between the groups. However, annual rate of FEV1 decline was faster in COPD patients with symptom variability than in those without symptom variability (-32.3 ± 21.1 vs. -26.2 ± 17.9 mL/year, P = 0.010). Conclusion: COPD patients having symptom variability showed accelerated decline of lung function.