One in Five Patients with Asthma, COPD, or Asthma and COPD, Has ACO Overlap

June 18, 2019

Twenty percent of patients with either or both asthma and COPD have an overlap of symptoms.

Asthma and chronic obstructive pulmonary disease (COPD) are both conditions that can make it difficult to breathe and it’s possible to have both conditions at the same time. An NIH study found that about 20% of people with COPD, asthma, or both conditions had an overlap of symptoms, or Asthma-COPD overlap (ACO).

The study sought to estimate how often and in what ways symptoms overlapped among patients who are currently diagnosed with asthma, COPD or both. The study concluded that one in five individuals with a diagnosis of COPD, asthma, or both in primary care settings have an overlap of symptoms based on current international medical guidelines.

To gather data, The Respiratory Effectiveness Group (REG),, followed individuals, 40 years and older, who had more than two primary care visits during a two-year period in the United Kingdom's Optimum Patient Care Research Database (OPCRD). Individuals were classified based on diagnostic codes. REG is an a not-for-profit international initiative researching respiratory medicine.

While individuals diagnosed with ACO tend to be over 40, they are generally younger than people who are diagnosed with COPD. Besides the study’s age requirement, participants were also asked whether they had a history of smoking or still continued to smoke. Data was also included on whether the participants continued to have trouble breathing after using a bronchodilator.

The 2,165 participants broke down into the following categories: There were 1,015 participants with COPD only, 395 with both asthma and COPD, and 755 diagnosed with asthma only. Patients with ACO had an average age of 70 years. Study participants were 60% men and 73% former smokers. Sixty-six percent were either overweight or obese.

Patients with an ACO classification were also likely to have other medical conditions, including diabetes (53%), cardiovascular disease (36%), hypertension (30%), eczema (23%), and rhinitis (21%).

While both asthma and COPD can make breathing difficult, these conditions are different in an important way. Asthma symptoms can come and go, often prompted by an allergic reaction, but COPD symptoms are constant and can worsen over time. COPD is often caused by breathing fumes that irritate the lungs. Research has not yet confirmed exactly how the two conditions are related but a diagnosis of ACO can better address the mix of symptoms, helping to not only control asthma, but prevent COPD symptoms from worsening. More research is needed to clarify exactly how ACO affects patients.