Managing ACOS: The Asthma, COPD Overlap Syndrome

“ACOS is not an entity unto itself; it’s not a typical syndrome,” Brian Bizik, MS, PA-C, Asthma and Allergy of Idaho and Nevada, Immediate Past President of the American Academy of Physician Assistants in Allergy, Asthma, and Immunology, told MD Magazine as AAPA 2017.

Bizik explained that there are patients who have a primary diagnosis of COPD, but also share features that an asthma patient might have. And likewise, asthma patients who may have had asthma for a long period time start to develop symptoms that really mimic a long term COPD patient. “In this case we’re talking about a disease state like COPD where patients also have an overlap of symptoms with a separate disease state like asthma. And it makes a big difference in diagnosis and treatment, which is why it’s so important.”

According to Bizik, results from COPD gene studies and other research papers have suggested that about 15% of patients with COPD have features that give them an asthma overlap that’s significant enough to make a clinical difference. They may have a history of asthma, diagnosis of asthma as a child, or some of those traits that look more typically like asthma patients, but they are clearly COPD patients.

Bizik said experts haven’t quite yet nailed down the number of how many patients with asthma also have features of COPD, but he believes it’s probably in the same 10-15% range — especially patients with asthma who may have smoked for a long period of time. They may have had been diagnosed with asthma (or allergic asthma) as children, but over time, they’ve smoked and start to exhibit more signs of a typical COPD patient.

Bizik explained that he aims to help people visualize their patients. If one patient’s primary diagnosis is COPD, but also exhibits some asthma-like symptoms, clinicians should treat the patient as though he has COPD, using the GOLD guidelines (or whatever the clinician is most comfortable with). But, Bizik emphasized that clinicians should look at some of those features to find out whether he has eosinophilic asthma or allergies that would benefit from a referral to an allergist.

Likewise, if someone has asthma, but they’re starting to develop features that look more like COPD, clinicians should assess whether the patient still responds to an inhaled cortical steroid therapy. “There are questions you want to ask, especially when you’ve been treating patients for a long period of time: Are they starting to change a little bit? Have I overlooked some more typical asthma features even though I’m treating them for COPD?” Bizik stressed not to overlook some of those clues.