What is ACOS and how it’s treated?

What is ACOS and how it’s treated?

When a patient suffers from clinical features of both asthma and COPD (chronic obstructive pulmonary disease) it is referred to as ACOS (asthma-COPD overlap syndrome).

It is not always easy for doctors to distinguish asthma from COPD, particularly in older adults and in smokers.

The symptoms of asthma and COPD

The symptoms can appear to be quite similar. The typical features of asthma include wheezing, shortness of breath, chest tightness and a cough caused by chronic airway inflammation.

The symptoms of COPD include an ongoing mucus-producing cough (a smoker’s cough), shortness of breath, wheezing and chest tightness. Both conditions lead to chronic airflow limitation – in short, it’s difficult to breathe.

When a patient has features of both of these lung conditions, in other words ACOS, they are said to “have frequent episodes where their symptoms become worse, they have a poorer quality of life, their lung function deteriorates more quickly, their chances of dying is higher, and they use a far greater portion of healthcare resources than a patient who only has asthma or COPD.”

Who gets ACOS?

Patients with ACOS are mainly smokers with a history of asthma or non-smokers with long-standing asthma who developed an airflow obstruction that was not reversible.

Prevalence of patients with ACOS have been reported to be between lower than 10% in patients younger than 50, and over 50% in patients older than 80. Prevalence varies according to gender and age.

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.


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