DIAGNOSIS OF COPD
THE DIFFERENCE
What distinguishes emphysema from Asthma ?Both happen in the airpipes called the bronchi that are the tubes which allow air to pass into and out from the lungs. Emphysema occurs due to the build up of mucus in the bulbous sacks that lie at the end of the air pipes - they are called the alveoli. Asthma occurs due to muscles causing constriction of the pipes themselves or when they become partially blocked with sticky mucus - sometimes both.These words are inspired by an article by Chris Le Roy. The full article can be read on the internet just now - recommended reading. To find it :
Type 'difference between asthma and emphysema' into the Google box (go Worldwide, not UK only). Click Google Search. On the list that comes up, find : "Asthma: Asthma versus emphysema" and click on it. The article should come up. David
DIAGNOSIS
OK so you’ve had a spirometer (that machine you blow into) test and it has measured your FEV1 and you’ve had an X-ray and other tests and have been told you have COPD.
This page is complicated but your GP might be able to explain it to you better than we can !!
What happens next?
Well, the FEV1 result is the one that really matters at the present time and is used to define how severe your COPD is. Let’s define again this FEV1 statistic. You blow into the tube, preferably sitting down and as hard as you can and for as long as you can, without coughing or pausing. If you are normal than most of the air in your lungs will be blown out in one second, like somebody who can blow out forty candles on a birthday cake all at once. But if you have COPD this doesn’t happen and to empty your lungs you have to blow out for say fifteen seconds and in the first second, the hardest blow part may only blow out one or two candles. So, FEV1 means Forced, for forcing the air out as hard as you can, Expiratory meaning breathing out not in, Volume, meaning the most air you can breathe out in 1, meaning one second. Now the GP or respiratory nurse will read the computer print out and interpret the result.
How does the computer or person do that?
Well your age and height will be known and the FEV1 that is expected at your age will be known. Remember that everybody’s FEV1 declines after about 30. So it’s a simple matter to put your FEV1 over the expected FEV1 and multiply by 100. And the result is given as a %.
When John did it back in 2002, his FEV1 was 0.86 and his expected FEV1 at the age of 58 and a height of 5 feet 8 inches was 3.16. So 0.86 over 3.16 times 100 equals 27%. “27%? He exclaimed, "27% of normal!”. The consultant was hesitant and then said “you have Severe Emphysema” pointing at the X-rays and then added “don’t worry, it’s not life threatening”. “Oh great” John said “Not now maybe, but how about later?” The consultant shrugged his shoulders “Nobody knows. You might be hit by a bus for all I know.” Why do people always come up with that? thought John - and then he exclaimed "I’m now paranoid about buses!"
Since 2002 John's FEV1 declined to 0.5 by 2007, which is a larger drop than should be expected over 5 years. However, in 2002 it was probably on the verge of dropping anyway. Average annual decline is around 0.03 if you do not smoke, twice that if you do.
So how do you know how serious your FEV1 figure in % terms really is?
NICE or the National Institute of Clinical Excellence (2004) states the following;
If your FEV1% is between 50- 80 %, then you have MILD COPD. If your FEV1% is between 30-49%, then you have MODERATE COPD.
If your FEV1% is below 30%, then you have SEVERE COPD.
If you don't understand this page, your GP or consultant will tell you whether you have mild, moderate or severe COPD or asthma or nothing at all !!
You can see now why John was so shocked. Unfortunately many of the symptoms of COPD only appear when you have reached the severe stage and that is when it is usually diagnosed. But all smokers over 40 beware – you may have the disease but don’t know it, and if you are treated early enough and STOP SMOKING then you may never have the symptoms at all. John kept wishing he'd known that and had a simple test.
30,000 people in the UK die of COPD and its complications every year and it is one of the fastest growing diseases. John gave up smoking two years before he was diagnosed but the damage to his lungs had already been done. And it is irreversible. But he knew he could slow down the progression of the disease and prolong his life, provided that he did not smoke again, took his medications and avoided extremes of cold and heat, ate sensibly and frequently, exercised and avoided people with infections.
John held that he would encourage anyone who smokes and is worried that there may be something wrong, to answer the questionnaire and see if they might be affected by COPD or some other ailment. If you have what you think is only smoker's cough, have it checked immediately. Don't forget it might not be serious, but on the other hand early diagnosis might save or prolong your life.