Expert: Kevin Smith - 10/4/2009

Question
Dear Kevin

Sue is not here anymore I'm afraid. I'd like you to just answer my one and single question. If my spirometry result is PD20FEV1: 0.89 mg/ml which kind of asthma do I have ? Is it mild , moderate or severe? Please answer this simple question of my. The answer matters to me extraordinarily.

Thanks a lot
Soheil

Answer
Hi Soheil,

Unfortunately, it's not going to be that easy to assign what severity of asthma you have based on that number:

It needs to be compared to the same test preformed several times and the differences noted.

It needs to be compared to another test called FVC

Your age, sex, height, weight, overall health, etc need to be considered.

However, for a very down-and-dirty idea of where you stand ( in other words, not a diagnosis, but a guideline )for FEV1:

"Patients with mild persistent asthma are said to have FEV1 values of more than 80% of predicted, patients with moderate persistent asthma have values of 60 to 80% of predicted, whereas those with severe persistent asthma have values of less than 60% of predicted"

as per: http://ajrccm.atsjournals.org/cgi/content/full/169/7/784

In order to get your predicted score, you can use a formula such as those at:

http://www.medal.org/visitor/www%5CActive%5Cch8%5Cch8.01%5Cch8.01.01.aspx

but you should be aware of which formula your test was using in order to keep your calculations accurate. Also, be aware that these calculations are for FEV1, not necessarily PD20FEV1.

That's about all I can provide for you at the moment - in order to get a 'keyword' diagnosis, many areas of your medical background have to be considered.

Good luck!