Lung function test? % means fev1/fvc?

[Jastini]

Hello.

I’m a asthmatic, which have Been having issues for sometime now.

Yesterday I did a spirometry test, and my doctor told me, I have a lung function of 76% compared to my age (25m).

Now I wonder if that is 76% is my fev1/fvc results.

Cause, as far as I can read, this isn’t supposed to be 100%, or have I misunderstood?

My doctor looked at me, as if things are not quiet good....

[hypercat54]

Hi your lung function is your FEV1 only and is the most important figure. It is worked out on the basis of the normal for your age group, sex etc. So if the normal for this was say 90% then your percentage would be out of that ie 76% and not out of 100%.

I hope this clarifies it a bit for you. x

[Phil40 in reply to hypercat54]

So the percentage is taken from what your lung capacity should be at that age.

So a 25year old with a 76% FEV1 will have a different overall actual FEV1 than a 50 year old with a 76% FEV1?

That doesn’t seem right to me but I am probably just getting it all confused again.

[Ergendl in reply to Phil40]

Everyone's lung function declines naturally with age. That's why the readings are compared with someone your age. At my last lung function test, my reading was accidentally compared with a 33 year old, when I'm 64, which made it look as if my lungs had declined a bit. However, my "lung age" is now 63, which is a great improvement on last year's 80.

[Phil40 in reply to Ergendl]

That makes sense. I try not to get too lost in the numbers as I always forget what means what.

This medical game is trickier than it looks. No wonder there are so many doctors that are sh

[soulsaver]

I'm probably over explaining here because, albeit with good intentions, there is erroneous info perpetuated on this site.

So:

FEV is a volume ( not a %).

Fev1 is the volume, usually in litres, of air you can blow out in 1 second from fully inflated lungs.

That result is then compared to the 'normal' volume expected from someone of your gender, height and age based on stats gathered over many years from (thought to be) healthy individuals.

So if your Fev1 is reported to you as 76% it means your best blow volume is 76% of what would be expected from healthy lungs of a person of same gender height and age as you.

Now if your Fev1/Fvc was 76%, that would not be 'obstructed' and the Dr would be over the moon if a diagnosed asthmatic could consistantly hit that result.

So the Dr must have meant FevI percentage of expected.. But you probably best ask them.

[Jastini in reply to soulsaver]

Thank you very much for this response. (and all of the others) I can understand why my doctor was concerned if u only blew 76% fev1 at my best blow. I guess this is not what you’d suspect from a 25 year old

[soulsaver in reply to Jastini]

You can look up what you should be achieving on a peak flow chart and monitor your control by graphing daily measures. You can get a manual meter on prescription, or buy one for £10 or so on amazon.

You should have been encouraged to keep a PF diary so your asthma control can be monitored and exacerbations spotted in good time?

[Jastini in reply to soulsaver]

I have been doing this for the past year. My daily pf is 550, and for male my age normal is 610

[Superzob in reply to Jastini]

I think you need to be careful not to read too much into this figure of 76%. The AVERAGE person of your age would score 100%, but 95% of people fall within what is called the 95 percentile range. This is 80-120%, so you are just below the bottom of the "normal" range (as you can see, some people are lucky enough to have amazing lungs, 20% above the average!).

I've calculated that I may have started out where you are now, but then I'm 69 with 50% lung function, but very few symptoms. In fact, with treatment started only 3 years ago, my lung function has increased to 63%. Early treatment in your case may be a very effective option.

[Phil40 in reply to soulsaver]

Yes that answer. That’s the one I meant

[Jastini]

I’d very much love to hear stories about people experiencing improvement in fev1

[Gary56]

This might help.

.

kivihealth.com/blog/underst...

Your FEV1is important when you’re having an attack, not so much as when you aren’t. Possibly the % is based on Fev1/Fvc?

[soulsaver in reply to Gary56]

Fev1 for asthma sufferers is MORE important when not having an attack because if it leaves the normal expected results it can indicate an attack or infection is imminent. You then need to refer to your personal agreed action plan - which maybe increase inhaler/ see respiratory nurse/Dr/a&e .

You don't need a measure to tell you you're having an attack

[Gary56]

I stand corrected on that point, thank you, but as a standard indication of lung function, not so much. Many factors are involved FEV/FVC, DLCO etc. Though I assume, as an indication of future attacks, may give a clue to the severity.

[Jastini]

Thank you for all the answers. Really appreciate the comfort this community provides

[Gearoidin]

I was told last week that my FEV1 had gone up from high 70s to high 80s....am 62 with bronchiectesis. I was delighted but my consultant said it wasnt all that relevant, that FEV can go up or down on any particular day. I must say I wondered why bother measuring it so?