Chronic obstructive pulmonary disease – diagnosis and classification of severity

Abstract

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