Hi , and thanks for your post and question - it's a good one! I see my good colleague, , has provided a thorough and comprehensive answer. I agree with all she has shared with you.
Since Rebecca spoke about intrinsic and extrinsic causes of asthma, I thought you might gain some additional insight from this article (also authored by a colleague and respiratory therapist), in which he explains the ramifications of both intrinsic and extrinsic asthma: https://asthma.net/living/extrinsic-vs-intrinsic.
I do hope you find the information is helpful for you!
Wishing you well,
Leon L (author/moderator asthma.net)