ABSTRACT
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.
KEYWORDS:
Article highlights
In the present 1-year follow-up observational study on 237 patients with stable phase chronic obstructive pulmonary disease (COPD) and regular inhalation therapy, mean COPD assessment test (CAT) and modified Medical Research Council (mMRC) scores at T0 were 10.55 and 1.2, respectively.
The majority of patients pointed out mild symptoms, and the mean CAT score at T0 did not differ after subdividing our population in the four spirometry Global initiative for chronic Obstructive Lung Disease (GOLD) stages. In the year of follow-up, FEV1 and hyperinflation indexes improved. CAT score was significantly associated with mMRC, residual volume (RV), and RV/total lung capacity %.
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 systems of symptom evaluation after 1 year.
Author contributions
M.R.V., V.L., F.P., and O.R. conceived and designed the study, interpreted the data, and are the guarantors for the study. E.R. performed the statistical analysis and takes responsibility for the integrity and the accuracy of data analysis, and had full access to all of the data of the study. M.R.V., M.L., and F.P. wrote the manuscript. M.R.V., M.D., S.D., A.C., F.P., M.L., E.R., and O.R. assisted in literature search and interpretation of data and contributed substantially to the discussion of the article content and review and/or editing of the manuscript before submission.
Declaration of interest
The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.
Reviewer disclosures
Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.