Updated 07 September 2017

ACOS – the little known syndrome asthma sufferers need to know about

Most people know a bit about asthma but very few of us have ever heard of asthma-COPD overlap syndrome (ACOS) - here's what you need to know.

The 3rd of May marks World Asthma Day – a global initiative aimed at improving asthma awareness and care across the globe. 

While most people know a bit about asthma, very few are aware of asthma-COPD overlap syndrome (ACOS) – a condition that often goes undiagnosed. 

When a patient has clinical features (symptoms) of both asthma and COPD (chronic obstructive pulmonary disease) it is known as ACOS.

Read: 13 quick facts on COPD

The symptoms of asthma and COPD

Asthma and COPD can cause similar symptoms – a fact that can make it difficult for doctors to differentiate between the two.

This is especially in older patients and people who smoke. Both asthma and COPD restrict airflow, making it difficult to breath.

Who gets ACOS?

ACOS is most commonly diagnosed in the following two groups of people:

  • People who have asthma and smoke
  • Non-smokers with long-term asthma and irreversible airflow obstruction

The prevalence of ACOS increases with age and varies according to gender.

Read: Asthma and children

What treatment is recommended?

Once the condition has been diagnosed, it is recommended that patients be referred for specialised care as outcomes for ACOS are often worse than for COPD or asthma alone.
Studies are ongoing with regards to the precise definition and most effective treatment for ACOS. 

Read More:

Psychological aspects of living with COPD

How severe is your asthma?

Chronic obstructive pulmonary disease (COPD) - from Natural Standard


Global Initiative for Asthma (GINA) and GOLD (Global Initiative for Chronic obstructive lung diseases). Global Strategy for Asthma Management and Prevention (2014). [online] Available from Page 3. Accessed April 25 2016. (2014) Official website of the American College of Allergy, Asthma & Immunology.[online] Available at (Accessed on 25 April, 2016). (2013) Official website of the National Institutes of Health. [online] Available at (Accessed 0n 25 April 2016) GINA & GOLD op.cit. p.2

Benfante, A. (2014) The asthma-COPD overlap syndrome (ACOS): hype or reality? [online]. Available at: (Accessed on 25 April, 2016). Ibid.

Blair K, Evelo A (2013). COPD: Overview and survey of NP knowledge. 2013. Nurse Practitioner: 38(6); 18–26.  GINA & GOLD, op. cit. p.3

This article was brought to you by Cipla Medpro South Africa (Pty) Limited and its affiliates.
Find out how Cipla is advancing healthcare for all in South Africa.


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