Phenotypes of COPD in Central and Eastern Europe

Chronic Obstructive Pulmonary Disease (COPD) is a significant cause of morbidity and mortality in Europe and a major consumer of resources in both primary and secondary healthcare (1,2). Both clinical features of disease severity and quality of COPD patient care may have substantial influence on disease outcomes. Traditionally, COPD has been categorized using the FEV1 (forced expiratory volume at one second ) - based GOLD (The Global Initiative for Chronic Obstructive Lung Disease) classification . Other factors independently associated with survival include age, dyspnoea, health status, hyperinflation, gas exchange abnormalities, exacerbation frequency, exercise capacity, pulmonary hemodynamic, and nutritional status (3). Together these factors explain some of the existent heterogeneity within each GOLD stage in terms of symptoms, exacerbations, quality of life and exercise capacity (4). Recently, interest has emerged for the identification of clinical COPD phenotypes, as defined by ''a single or combination of disease attributes that describe difference between individuals with COPD as they relate to clinically meaningful outcomes'' (5). Many previous studies have attempted to identify and quantify the prevalence of different phenotypes of COPD using populations of various sources, severities, and particularities. Yet there is no consensus on the number and definition of different phenotypes. However, there must be a compromise between the oversimplification of the term COPD as a definition that encompasses the entire spectrum of patients with incompletely reversible airflow obstruction caused largely by smoking and the complexity of considering each patient individually as an orphan disease. The most frequently reported phenotypes are emphysema and chronic bronchitis, along with a subset of asthma sufferers. Recently, an extended list of proposed phenotypes have been proposed (6) including: (A) infrequent exacerbators with either chronic bronchitis or emphysema; (B) overlap COPD-asthma; (C) frequent exacerbators with emphysema predominant; and (D) frequent exacerbators with chronic bronchitis predominant. While there is consensus of substantial, but not complete, overlap among these phenotypes, the distribution of these phenotypes may differ widely between different countries and healthcare systems. Thus, the objectives of this study are to better understand the patient characteristics and treatment patterns of those diagnosed with COPD between different CEE countries. Knowledge of this information may provide insight into the variability of phenotypes between different healthcare systems and may subsequently contribute to a better understanding of the factors associated with patient outcomes and have the potential to improve the care of COPD patients.