My fondness for waking up to the sound of the radio was put severely to the test on Sunday morning when the words ‘should consult their GP’ drifted nonchalantly into my dreamy subconscious. The correct response, of course, since I am a husband and father on Sundays and not a GP, is to groan to myself: ‘What have they done now?’, hide under the pillow and hope it will all go away. Curiosity got the better of me, however, and shortly after I joined the ranks of other disbelieving GPs on Twitter, threatening to drown out the dawn chorus with our tweeted mutterings.
What ‘they’ (which is the Department of Health (DOH) in this case) have done is to launch a publicity campaign advising anyone with a cough for more than three weeks to see their GP, because it could be a sign of lung cancer. GPs are all for helping people with lung cancer, but no-one was saying that this was a good idea. There was a mixture of stress about a tidal wave of expectorating patients flooding our Tuesday surgeries (why does the Government have to launch these initiatives on a Bank Holiday weekend when we only have a 4 day week to mop up the fallout?), to concern about raising unnecessary anxiety, the harm of unwarranted chest x-rays and the overall cost to both patients and the health service of this newly trumpeted advice.
Anyone with a cough? Really? Taken at face value, the advice would mean that a baby with a cough for more than 3 weeks should see their doctor to exclude lung cancer – clearly this is ridiculous, but if the campaign makes no mention of age then how are the public meant to know who is too old and who is too young? And 3 weeks? Did they really mean 3 weeks? Don’t the DOH know that 35% of people with a simple viral respiratory infection will cough for 3 weeks? Of course they do – their own publicity poster on coughs and colds states that ‘Colds can last about 2 weeks and may end with a cough’ so don’t worry, and certainly don’t think about antibiotics – about 2 weeks must mean that some last 3 weeks, surely? Now this means that the public are meant to understand that a normal cough can certainly last 2 weeks or more and is nothing more than a harmless virus, but if your cough lasts 3 weeks then DON’T DELAY, IT COULD BE CANCER! Hmmm…can’t help feeling we need a large dose of common sense here!
So why have the DOH done this? Well, lung cancer is worth looking at because survival rates are currently very poor – with approximately 40% of patients being alive 1 year after diagnosis, and only 15% surviving 5 years. Earlier diagnosis could make a difference in some (but not all) lung cancers, and who would not want to achieve better survival from cancer? Lung cancers associated with cough are more likely to be in a place where they can be fully removed (and so cured) by surgery, and so cough is a better symptom to focus on than, for instance, breathlessness or chest pain (by the time you have these symptoms with lung cancer you are not very likely to be cured with treatment). They have chosen 3 weeks in part because of something called ‘slippage’ – the tendency for public health messages to be watered down. If you say ‘drink no more than 14 units of alcohol’, people are likely to assume that 21 wouldn’t be too bad, if you advise people that their cholesterol should be below 5.0 then 5.5 sounds ok, and if you say 3 weeks for a cough, then people might just go to their doctor after 4 or 6 weeks. The problem is that we are all wonderfully different when we behave as patients. Some will ‘slip’ far further then 6 weeks (or even not go at all – maybe if it could be cancer they don’t want to know) while others will now present to the doctor without fail on day 22 of any cough.
Let us assume that a person has lung cancer, and is just beginning to get symptoms from it. We could put that person into one of four categories like this:
Those in the blue sections do not need this campaign, as they will see their doctor early anyway, while those in the white quadrant will not be helped by the advertising either, as sadly their cancer will already be too advanced once it has started to give symptoms so going earlier will not change the outcome. The red quadrant, therefore, is the target group – those who have cancer which could be treated, but whose natural tendency is to see their doctor late. The questions then, are these: How large is this group? Will the campaign reach them, or are they the sort of people who don’t respond to advertising campaigns? And will the earlier pick up really lead to a better survival? On the other side of this argument also lies the potential harm of the campaign – how many people who don’t have cancer will see their doctor unnecessarily, worry needlessly and be exposed to chest x-rays that do not reveal anything of concern?
Well there has been a pilot study that answers some of these questions. In response to a similar, local advertising campaign people were nearly twice as likely to see their GP if they had a cough for more than three weeks, and the referral rate for chest x-rays went up by 20%. While this was hailed in the study as evidence that the intervention was successful, we must remember that these are not, in themselves, good things. In fact appointments with a GP and chest x-rays must be seen as costs in this programme, not benefits, and the question is – is it worth it? More positively there was an increase in the lung cancer diagnosis rate of 27% in the study period. Even this, however, is not the ultimate goal, which is better survival from lung cancer. The extra cases of lung cancer were spread across all stages of the disease from early to advanced, and so many of them would not fall into the crucial red quadrant in the above diagram. The study authors concluded that a larger study was required, but, as so often happens with pilot studies, it has been hailed as a success and a national programme rolled out.
So where does that leave us? In need of a good dose of common sense! The DOH know that a public health message has to be simple in order to hit home – and so they have reduced this to a one-liner: Cough for 3 weeks = see your GP. The GP is left to fill in the details. Well here’s my take on it:
Certainly we should be mindful of lung cancer in people who are at risk. A smoker over the age of, say, 40 with an unexplained cough for 3 weeks would do well to take the advice at face value – I would want to do a chest x-ray. If the same person coughed up blood, I’d be concerned enough to do an x-ray even if it only happened once. On the other hand, if you are young or have never smoked, but your cough is dragging on, we might decide to do an x-ray at some stage, but are far more likely to sort your cough out if we look for other causes – like asthma, allergic rhinitis or heartburn. Certainly a cough that goes on much beyond 4 weeks is worth seeing your doctor about – but in most cases this won’t be because we are worried about lung cancer, it will be because the cough is driving you and your family mad, and there might be something we can actually do about it!
