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