@article{3108410,
    title = "Chronic obstructive pulmonary disease with mild airflow limitation: Current knowledge and proposal for future research – A consensus document from six scientific societies",
    author = "Rossi, A. and Butorac-Petanjek, B. and Chilosi, M. and Cosío, B.G. and Flezar, M. and Koulouris, N. and Marin, J. and Miculinic, N. and Polese, G. and Samaržija, M. and Skrgat, S. and Vassilakopoulos, T. and Vukić-Dugac, A. and Zakynthinos, S. and Miravitlles, M.",
    journal = "International Journal of COPD",
    year = "2017",
    volume = "12",
    pages = "2593-2610",
    publisher = "Dove Medical Press Ltd",
    doi = "10.2147/COPD.S132236",
    keywords = "bronchodilating agent;  budesonide;  corticosteroid;  ipratropium bromide;  muscarinic receptor blocking agent;  placebo;  tiotropium bromide, airflow limitation;  airway obstruction;  cardiopulmonary exercise test;  chronic obstructive lung disease;  comorbidity;  computer assisted tomography;  disease exacerbation;  dyspnea;  exercise tolerance;  follow up;  forced expiratory volume;  forced vital capacity;  human;  hyperinflation;  lifestyle modification;  lung diffusion capacity;  lung emphysema;  lung gas exchange;  lung volume;  mortality rate;  pathophysiology;  physical activity;  prevalence;  quality of life;  respiratory tract inflammation;  Review;  smoking cessation program;  spirometry;  thorax radiography;  adult;  aged;  animal;  chronic obstructive lung disease;  consensus;  female;  lung;  male;  medical research;  methodology;  middle aged;  pathophysiology;  predictive value;  procedures;  prognosis;  pulmonology;  risk factor;  severity of illness index;  smoking;  standards;  very elderly;  vital capacity, Adult;  Aged;  Aged, 80 and over;  Animals;  Biomedical Research;  Consensus;  Exercise Tolerance;  Female;  Forced Expiratory Volume;  Humans;  Lung;  Male;  Middle Aged;  Predictive Value of Tests;  Prognosis;  Pulmonary Disease, Chronic Obstructive;  Pulmonary Medicine;  Research Design;  Risk Factors;  Severity of Illness Index;  Smoking;  Spirometry;  Vital Capacity",
    abstract = "Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality and morbidity worldwide, with high and growing prevalence. Its underdiagnosis and hence under-treatment is a general feature across all countries. This is particularly true for the mild or early stages of the disease, when symptoms do not yet interfere with daily living activities and both patients and doctors are likely to underestimate the presence of the disease. A diagnosis of COPD requires spirometry in subjects with a history of exposure to known risk factors and symptoms. Postbronchodilator forced expiratory volume in 1 second (FEV1)/forced vital capacity <0.7 or less than the lower limit of normal confirms the presence of airflow limitation, the severity of which can be measured by FEV1% predicted: stage 1 defines COPD with mild airflow limitation, which means postbronchodilator FEV1 ≥80% predicted. In recent years, an elegant series of studies has shown that “exclusive reliance on spirometry, in patients with mild airflow limitation, may result in underestimation of clinically important physiologic impairment”. In fact, exercise tolerance, diffusing capacity, and gas exchange can be impaired in subjects at a mild stage of airflow limitation. Furthermore, growing evidence indicates that smokers without overt abnormal spirometry have respiratory symptoms and undergo therapy. This is an essential issue in COPD. In fact, on one hand, airflow limitation, even mild, can unduly limit the patient’s physical activity, with deleterious consequences on quality of life and even survival; on the other hand, particularly in younger subjects, mild airflow limitation might coincide with the early stage of the disease. Therefore, we thought that it was worthwhile to analyze further and discuss this stage of “mild COPD”. To this end, representatives of scientific societies from five European countries have met and developed this document to stimulate the attention of the scientific community on COPD with “mild” airflow limitation. The aim of this document is to highlight some key features of this important concept and help the practicing physician to understand better what is behind “mild” COPD. Future research should address two major issues: first, whether mild airflow limitation represents an early stage of COPD and what the mechanisms underlying the evolution to more severe stages of the disease are; and second, not far removed from the first, whether regular treatment should be considered for COPD patients with mild airflow limitation, either to prevent progression of the disease or to encourage and improve physical activity or both. © 2017 Rossi et al."
}