As an alternative we’re considering to define asthma/COPD overlap as either 1) a diagnosis of COPD with asthma in the history, or 2) a diagnosis of asthma with COPD in the history (with the 1st option more frequently occurring).
Did someone encounter this issue before or does anyone have a suggestion for a different definition (or a concept that I overlooked)?
Yeah, typical problem. This concept is too granular, and the source codes are not mapped to it, even though it sounds like a concept capturing both Asthma and COPD. In fact it captures the patients that have both asthma AND COPD, while you are looking for something that is asthma OR COPD.
You need to go one level up. There you got Asthma and Chronic obstructive lung disease. Which is why you want to use Atlas and check the record counts (RC), it will tell you immediately if no data support this concept (you are “below the clouds” in the jargon).
Though I am not a pulmonologist, I have an experience investigating the effect of rate control medication in patients with COPD or asthma (ref).
To my knowledge, the asthma/COPD overlap syndrome is relatively newly suggested disease entity, of which definition remains elusive.
It may not be able to be defined by using one concept ID because this disease does not exist in ICD 9/10 code system (too novel disease entity).