The methods other than spirometry in the early diagnosis of COPD

Chronic obstructive pulmonary disease (COPD) is a major cause of mortality and morbidity around the world. The diagnosis od COPD is based on the presence of clinical symptoms and the fact that the ratio of post-bronhodilator forced expiratory volume in 1 second to forced expiratory vital capacity(FEV1/FVC) is less than 0.70. Persistent limitation of airflow which is a characteristics of COPD is reproducible and most common lung function test that is why it is usually measured by spirometry. The small airway diseases and the parenchymal destruction play a role in the pathogenesis of COPD at different rates over time resulting in chronic airflow limitation. These pathologies are not always together at the same time and the contribution of those to the development of COPD differ from one individual to another. The pathophysiological involvement of small airways in COPD has been confirmed. When the obstruction of the small airways occur either by mucus, smooth muscle hypertrophy, inflammatory infiltration or air wall thickening; then the consequence is the increased resistance and ventilation impairment. The parenchymal destruction can be estimated via scanning and at the initial assessment of a COPD patient, it gives information about the concomitant pulmonary diseases and/or differential diagnosis. There is an increasing interest on symptomatic individuals whose whose COPD diagnosis has not been confirmed yet with spirometry but diagnosis is based on alternative methods and approaches. Although these methods nowadays are commonly used for the clinical research, they will offer an opportunity to the clinician to find out the COPD patients at an early stage. Herein we will discuss the available methods other than spirometry in the early diagnosis of COPD before the overt disease is confirmed.