Clinical and Functional Characteristics of COPD Patients Across GOLD Classifications: Results of a Multicenter Observational Study

Abstract

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease. The severity grading systems proposed by the Global initiative for Chronic Obstructive Lung Disease (GOLD) have changed over time. The aim of the study was to evaluate if the different GOLD classifications can capture the complexity of the disease by investigating the distribution of lung function and clinical parameters across the GOLD classification systems. This was an observational, retrospective, multicentre study. COPD patients were stratified according to the GOLD severity grading proposed in the 2007, and to the ABCD assessment tool present in the 2011, and 2017 versions of the initiative. Data from body plethysmography, DLCO, comorbidities, exacerbation history, pharmacological therapy and eosinophil counts were collected. A total of 1360 patients (73.4% males) were included in the analysis. Overall, 37% of the patients were severe-very severe according to GOLD 2007. Compared with GOLD 2011, applying the GOLD 2017 criteria, the proportion of the at risk categories (C and D) was reduced by ∼23%. Impairment in inspiratory capacity, DLCO and the prevalence of emphysema paralleled the GOLD 2007 classification only. The proportion of patients with ≥ 200 eosinophils/µL was higher in GOLD 2007 stages 3–4 compared with stages 1–2 (P = 0.008). Eosinophil levels were similar across risk classes in GOLD 2011 and 2017. Overall, 41.8% and 52.4% of the patients in the low risk groups according to GOLD 2011 and 2017 were exposed to inhaled corticosteroids. The GOLD 2011 and 2017 classifications, despite exploring symptoms and exacerbations, might miss other relevant patients’ clinical characteristics such as lung function and phenotypes, which have a significant impact on outcomes and disease severity.

Keywords:

• GOLD document
• COPD
• airflow obstruction
• eosinophil
• phenotype

Acknowledgments

This study was conducted according to the amended Declaration of Helsinki and approved by the ethical committee of the Coordinator Center (no. 220-2016). All of the participants gave their written informed consent.

Disclosure statement

D.R. reports personal fees from AstraZeneca, Boehringer Ingelheim and Neopharmed Gentili. M.C. reports grants from Chiesi and personal fees from Chiesi, AstraZeneca, Boehringer Ingelheim, Novartis, Menarini, Mundipharma, Almirall, and Zambon. F.D.M. reports fees for research from Boehringer Ingelheim Italia S.p.A. and Novartis and grants for board participation or lectures from Boehringer Ingelheim, GlaxoSmithKline, Chiesi, Zambon, Novartis, Guidotti/Malesci, AstraZeneca, Menarini, Mundipharma, and TEVA. F.B. has received honoraria for lectures and advisory board membership from AstraZeneca, Boehringer Ingelheim, and Chiesi Farmaceutici, Dompè, Guidotti/Malesci, Glaxo Smith Kline, Menarini, Zambon, Novartis. C.M. has participated as a lecturer, speaker, and/or advisor in scientific meetings and courses under the sponsorship of AstraZeneca, Biofutura, Boehringer Ingelheim, Chiesi Farmaceutici, Glaxo Smith Kline, Guidotti, Menarini, and Novartis. PR participated as a lecturer and advisor in scientific meetings and courses under the sponsorship of Almirall, AstraZeneca, Biofutura, Boehringer Ingelheim, Chiesi Farmaceutici, GlaxoSmithKline, Menarini Group, Mundipharma, and Novartis. Her department was funded by Almirall, Boehringer Ingelheim, Novartis, Zambon, and Chiesi Farmaceutici. N.S. has participated as a lecturer, speaker, and/or advisor in scientific meetings and courses under the sponsorship of AstraZeneca, Boehringer Ingelheim, Chiesi Farmaceutici, Guidotti/Malesci, Menarini Group, and Zambon and has received financial support for research and for congress attendance from AstraZeneca, Boehringer Ingelheim, Chiesi Farmaceutici, Guidotti/Malesci, and Novartis. P. Santus reports grants and personal fees from Chiesi Farmaceutici, grants from AirLiquide, Pfizer, Almirall, and AstraZeneca, and personal fees from AstraZeneca, Boehringer Ingelheim, Novartis, Menarini, Malesci/Guidotti, Mundipharma, Valeas, Berlin-Chemie, and Zambon. P. Solidoro has received honoraria for lectures and advisory board membership from AstraZeneca, Boehringer Ingelheim, Bristol-Myers Squibb, Chiesi Farmaceutici, Dompè, Guidotti/Malesci, GlaxoSmithKline, Menarini, MSD, Mundipharma, Novartis, Biofutura Pharma (Alpha Sigma), and Biotest. GS, GP, AGC, and LS declare that they have no competing interests.

Data availability statement

The data are available upon request.