Change in Peak Flow Readings

I take my peak flow readings 3 times a day and record the best of the 3 blows.

The reading first thing in the morning is always the lowest which I believe is expected however has dropped progressively from 560 to 495.

My peak reading for the day as also dropped slightly from an average of 600 to 575.

I recently had a spirometry test which showed my asthma was well controlled at this time. Any ideas why my peak flow should be dropping please.

I have also started to get an ache in the centre of my chest, could that be due to using my peak flow meter.

Any advice would be appreciated as having controlled asthma and a reducing peak flow does not make sense.

[EmmaF91 Community Ambassador]

Spirometry only shows how you are at the moment you are doing it, it doesn’t represent how you’re doing long term.

Assuming 600 is your best score you’re still in the safe zone and technically controlled, even in the morning (and yes typically morning PF if done pre med is the worst), and of you’re not getting any of the asthma symptoms you doing need to worry too much, just keep an eye on it. It could be that outside factors are mildly affecting you (the weather/temp etc) and as these improve your PF will pick back up again. Conversely it could be that you’re heading into an issue as allergy season approaches and may continue to see small drops. Don’t worry, just monitor and if you drop to yellow zone on your asthma plan or become symptomatic then see your AN/GP.

For me PFM don’t give me a sore chest (unless I’m really symptomatic when I try), so no advice there. It may be nothing (just muscles aching cause you’re working them hard on the PFM) it could be something (the start of a tight chest, costocondritis etc etc) so again keep and eye and see someone if you get concerned.

Hope this helps

[Hidden in reply to EmmaF91]

Hi Emma, thank you for your reply.

I think you are probably right about muscle strain, as the ache has eased quite a bit but still there.

Yes my morning peak flow is always pre meds which is the advice on the Asthma UK website.

I just did my my midday reading which is back up to 600 which is all good news and shows my meds are doing what they are supposed to do.

As you say I am still in the green zone in the morning although the overall variation for the day is 17.5%.

When I have spoken to an Asthma UK nurse before they are looking for a much smaller variation however I am comparing pre med in the morning with post med during the day. I will give them a ring tomorrow and see what they say.

Thanks again for your response, it’s so useful to receive feedback from the forum.

[Redwine55]

I've only started a peak flow meter in the last couple of months (despite having asthma for over 50 years) and I have noticed similar results to yours.

My peak flow readings are lower than the ones you have, probably due to age difference, but the pattern is similar. I also have experienced a similar central chest pain on occasions since using the peak flow meter regularly so you may be right about the cause of that.

Despite not having recorded readings for very long I have noticed over time that my asthma is worse in cold damp conditions and better in warm dry weather, so the current weather could be affecting your results.

Hope this is of some use.

[Hidden in reply to Redwine55]

Hi Redwine, thanks for the reply.

My asthma was never a problem for 3 years and then I picked up some kind of virus at the beginning of November and have had problems ever since. So I’ve never experienced the effect of weather on my asthma, I can imagine damp weather causing a problem.

My morning reading does fluctuate and has picked up today, I’ve not coughed up any phlegm over the last 2 days so that may be related.

The chest pan I am not sure of so I am just taking one reading 3 times during the day for the next few days and see it that helps.

[Hidden]

That isn’t quite how you’re supposed to do it. You take it three times one right after the other and record the highest number. You just ignore the other too. You can do that three times a day, but always use it three times, record the highest and ignore the other two.

You also have to ignore small differences. The difference between 575 and 600 is insignificant although it is typical for the morning’s highest number to be slightly lower than what you get in the evening. There’s absolutely no reason for using a peak flow meter to cause discomfort unless you’re having a TERRIBLE attack.

Your biggest difference wasn’t a 10% difference. Doctors consider drops to be significant at 20%.

You’re just worrying too much about small differences. 😀

[Hidden in reply to Hidden]

Hi Suckitup, like the name.

Yes you are probably right that I’m getting stressed over what are small differences, have to be more positive.