My peak flow and my FEV1 are higher than the predicted, even when I get sick (for me <700 on the PF bad news, so is 110% on the FEV1). I found a few research papers on pubmed suggesting that PF and FEV1 are only sensitive to the medium to large airway function, and not sensitive to the small airway (<2mm) function. My FEF 25-75 has always been <80% predicted (sometimes<50%), but no consultant has ever paid any attention to these numbers, in 15 years I've had spirometry taken. I wonder why, and I also wonder if there are now more sensitive methods than spirometry and PF. E.g. I've read about "Impulse Oscillometry" (ios)-- anyone heard about this? Google showed that they do it at Cambridge (of course).
My symptoms are air trapping, chest tightness, inability to talk, waking up from breathless at night, chest tightness when changing body pasture, and exercise-induced asthma, But these are all self-reported, and they are not convincing to anyone with an authority to help -- they just stick a PF meter in my face and call it a day. Eos counts and IgE work better, but i must go off prednisone each time to get them elevated again. NO is normal.
Review Paper 1: ncbi.nlm.nih.gov/pmc/articl...
Review Paper 2: pubmed.ncbi.nlm.nih.gov/215...
Review Paper 3: rc.rcjournal.com/content/65...
pamphlet on IOS from the manufacturer:
You are without question correct in your analysis. I have the same problem (high FVC & FEV1, lower mid flows) and a defect in the Small Airways can indicate a worse quality of life (peer reviewed report)
As a mild asthmatic in childhood with a past history of light smoking (I had no detectable asthma at the time) I have also been cast aside by the medical community but that was two decades ago. I still have a negative methacoline test for asthma but positive for excercise induced.
I’m about to embark on a review after 20 years where I’ll request an IOS and a CT scan, both gold standard for SAD. IOS is available here but only in one lab with a 6 week wait. This surprises me because the tech is cheap and it’s being billed as a solution for primary care.
I’m personally hoping a new consultant may have more to offer and the thinking on mild disease & treatment has changed since my last review.
The question is if it is indeed SAD what can they do? Fostair has been formulated to reach the smallest airways, Singulair had been proven to have an impact and lastly NAC has shown to improve SA function. It may be worth speaking to your GP to get onto this course of medication.
I’ve read your past posts and see you’re well versed in all this. Here’s another report that may be of interest mayoclinicproceedings.org/a...
The problem as I see it is that most COPD”ers have abysmal small airway function but complain little so as someone with Asthma & you’re just over the LLN it’s passed off. This is where new thinking on obstructive disease comes into play, treat the symptoms not the numbers.
It’s not helped by the fact the jury’s out on the value or relevance of mid flow on spirometry.
I notice your FVC is outstanding, this could account for the lower mid flows, see article below:
pftforum.com/blog/it-it-tim...
May I ask which hospital IOS is available at? Seems easier to book than a CT scan (and the device may even be doable via DIY for IOS, not for a CT scan
).
Indeed, looks like there is a lot of overlap in reviews, between COPD and small airway asthma. I see that some inhalers (like Qvar) have smaller aerosol particles. However, I am not sure if they adjust per the surface area of small airways (supposedly much larger than the larger airways). In my mind, to make a proper effect the formulation should contain much more steroid for the small airway formulation, and then it probably will approach systemic amounts anyway (the alveoli might have a dimension of 2.5).
I am allergic to Fostair -- my face swells.