The association of patient-reported symptoms and clinical and lung function parameters in patients with chronic obstructive pulmonary disease in stable phase

Objectives: Few 'real-life' studies were conducted on the relationship between functional and clinical features in chronic obstructive pulmonary disease (COPD). We described the correlation between clinical and functional respiratory parameters in one-year follow-up observational study during stable phase COPD and regular inhalation therapy.Methods: In 237 patients, the impact of respiratory symptoms was evaluated using the modified Medical Research Council (mMRC) dyspnea scale, the COPD assessment test (CAT), and a self-assessment of patient's perceived COPD severity (Mapel scale) at baseline (T0) and after one year (T1).Results: Mean CAT and mMRC scores at T0 were 10.55 and 1.2, respectively. The majority of patients pointed out mild symptoms (values between 1 and 2 at Mapel scale). Mean CAT score at T0 did not differ after subdividing our population in the four spirometry GOLD stages. In the year of follow-up, FEV1 and hyperinflation indexes improved. CAT score was significantly associated with mMRC (p < 0.001), residual volume (RV) (p = 0.023), and RV/total lung capacity % (p = 0.011).Conclusion: The impact of symptoms in COPD stable patients was related to hyperinflation indexes and mMRC. There was no correlation between significant changes in CAT score and other symptom evaluation scores after one year.