Chronic obstructive pulmonary disease--diagnosis and classification of severity

Chronic obstructive pulmonary disease (COPD) is a common, progressive and preventable non-communicable respiratory disorder. It is often confused with asthma and poorly understood by many lay people. The primary cause of COPD is tobacco smoking, but in the South African (SA) context, biomass fuel exposure/household pollution, tuberculosis, HIV and mining exposure are additional important causes.There is a very high prevalence of COPD in SA and it is the third leading cause of mortality globally.The diagnosis of COPD is based predominantly on symptoms, i.e. progressive shortness of breath and cough in a patient with risk factors–usually smoking. Lung function testing is required to formally make the diagnosis, which places a significant hurdle in correctly identifying COPD in SA, given the limited access to spirometry in many areas. Spirometry is also required to grade the severity of lung function obstruction.Severity assessment, which is used to plan a management strategy (predominantly bronchodilators with inhaled steroids in severe cases), combines symptoms, lung function and exacerbations. Based on these 3 factors, a patient can be categorised into 1 of 4 groups and appropriate management instituted. Additional comorbidities, particularly cardiovascular and mental illness, should also be evaluated.Early identification of COPD, with further avoidance of an aetiological cause such as smoking, is key in preventing disease progression.Appropriate therapy, comprising non-pharmacological and pharmacological interventions and based on a comprehensive severity assessment, should result in symptom improvement and reduced risk for exacerbations.