Last month in the Tribune I published an article defending smoking.
Well, after weeks of reading mind-mangling academic and medical articles I have come up with the answer. Are you ready, it's a corker.
There isn't one.
There is no randomised, double blind, controlled trial to show that smoking causes cancer in humans. Nor is there a randomised, double blind, controlled study to show that it causes heart disease. There is also no controlled study to show that reducing smoking lowered the incidence of these diseases.
Unfortunately for us smokers, this does not mean that smoking is not harmful. It also does not mean that everyone has been lying about smoking being harmful. It just means that, like most things in life, the answers are not that simple. Thus, we have the substance of this article - trying to untangle the complexities of how and why smoking is linked to early death.
One of the many interesting things I discovered is how utterly impossible it is to find truly objective studies. Hello and welcome to humanity - everyone has an agenda. And if you think that the medical profession and anti smoking lobby groups occupy some high moral ground that is somehow above all that, let me tell you, you are profoundly wrong. Smoking and smoking cessation are highly emotional and highly lucrative subjects, two things that make it almost impossible for anyone to approach it objectively.
Want a specific example? Ok. Dr Michael Fiore, chairman of the national panel developing smoking cessation guidelines in America is the director of a research centre that has directly received over $1.4 million from the makers of nicotine supplements. They also pay him around $40K a year for honorariums and consulting work. Want to know what's in the smoking cessation guidelines that he is responsible for distributing to hospitals and GPs across America? Yep, you guessed it. Everyone should take nicotine supplement products because that will stop them smoking.
Interestingly enough, there is considerable evidence that nicotine supplements don't actually work. They may get you through the first six weeks or so, but you are more likely to take up smoking again within 18 months if you quit with nicotine products than if you go cold turkey.
I was quite surprised to find that the most effective thing you can do to stop in the long term is hypnotherapy. There are several reputable studies that showed significantly better long term results using hypnotherapy over nicotine supplements. Why is it, do you suppose, that doctors and national guidelines will recommend nicotine supplements, but will pretty much ignore something that has be proven to be more successful in aiding long term smoking cessation? Am I being too cynical in ascribing this to the influence of pharmaceutical companies, who make millions out of turning cigarette addicts into Nicobate addicts?
This sort of thing happens in Australia too. When the National Health and Medical Research Council (NHMRC) were putting together the recommendations for anti smoking legislation, they were sued for deliberately ignoring much of the literature that disproves the link between passive smoking and long term health problems. And a Federal Court Judge found this to be true. Despite this, all their recommendations (based on the supposed dangers of passive smoking) were pushed through and became law.
Bias is not limited to professional media and large corporations. While I have no means of profiting from this discussion, I did notice that I was far less sceptical of articles that described the benefits (yes, benefits!) of smoking than I was of anything describing its detriments. I, too, have an agenda you see.
However, I have tried to overcome my prejudices and here is what I have found.
Actually, before I launch into all the medical facts, let me make one point. Less than ten years ago it was accepted medical fact that stomach ulcers were caused by stress and/or poor diet. It was also accepted medical fact that bacteria cannot survive in the stomach because it is full of hydrochloric acid. This was fact and it was beyond dispute. Then a pathologist from Perth found what looked like live bacteria in the contents of someone's stomach. He thought this was a bit odd, but rather than say to himself that medical fact says these bacteria cannot exist and therefore these bacteria do not exist, he showed them to one of his scientist mates. The two of them spent a few years looking into it and found these bacteria only occurred in the stomachs of people suffering from gastritis and stomach ulcers. Terribly excited by this discovery, they tried to tell the world that they had found the cause (and the cure) for stomach ulcers. The scientific and medical communities glanced at their research and then joyfully scoffed and pitied the poor fools who were making such tits of themselves by publicly disputing known facts in this way. Three years later the poor fools had proven their hypothesis, won a Nobel Prize and made a couple of squillion dollars curing the world of stomach ulcers. The scientific and medical communities have maintained a sulky and resentful silence on the matter ever since.
The history of medicine is rife with this kind of story. All disease is the result of an imbalance in the four humours, leeches will fix everything, over-emotional women can be cured by a hysterectomy, cholera is caused by evil miasmas, bacteria are too small to have any effect on illness, mosquitoes cannot spread disease to humans, butter is good for you, butter is bad for you, all you need to do is sacrifice a good goat and all will be well with your village. All these things were known medical 'fact' at some point in history. Then someone came up with a new theory, the medical communities scoffed and pitied until, eventually, the evidence became overwhelming and unpalatable new ideas became generally accepted wisdom.
While I am not claiming that the detrimental effects of smoking are totally apocryphal, I am convinced that the health effects of smoking is not as comprehensively understood as it appears on the surface.
So, what evidence do I have for this claim? Well, firstly, as I stated earlier, there is no absolute proof that smoking causes early death. All the studies talk about risk factors. Smoking is implicated as a risk factor for lung cancer, heart disease, pancreatic cancer, stroke, premature facial wrinkles, impotence, cervical cancer, miscarriage, multiple sclerosis, chronic bronchitis, asthma, diverticulitis, diabetes, anal cancer (seriously), gum disease, fibrosis progression in chronic hepatitis C, macro proteinuria, Alzheimer's, hypertension, hepatocellular carcinoma, pelvic inflammatory disease, breast cancer, thyroid disease, tuberculosis, colorectal adenomas, restless leg syndrome, subarachnoid haemorrhage and renal disease, among others.
Smoking is also indicated as a significant risk factor in suicide and HIV infection (but not the progression to full blown AIDS). Hmmm…. but we'll come back to that in a moment.
So, what does 'risk factor' mean? It doesn't mean that if you smoke you will definitely suffer any or all of the diseases listed above, but it does mean that if you smoke you are more likely to have these diseases that you would be if you didn't smoke. How much more likely? Well, I can't tell you that. No one can. The interaction between risk factors in each individual is too complex to allow simple black and white answers.
Also, in the vast majority of diseases listed above, risk factors have only an epidemiological (statistical) basis not a medical one. Epidemiology is mathematical, not medical interpretation of data and the answers you get depends a great deal on what you are looking for and how you find it.
If you take a sample of 2,000 people and identify all the people who are infected by HIV and all the people who smoke and find a positive correlation between smoking and HIV infection then you have statistical proof that smoking is related to HIV infection. What you do not have is proof that smoking causes HIV infection. Clearly it doesn't. HIV infection is caused by blood to blood contact with someone who already has the virus. It is not caused by hugging, touching or smoking with someone who has HIV.
Also, you have to ask the right questions of your sample population to be able to establish correlations. It is entirely possible that there is a positive correlation between wearing orange jumpers and being infected by HIV, but no-one in their right mind is going to look for such a correlation and so no one has ever asked a population of HIV infected people whether they commonly wear orange jumpers.
Everyone studying a disease will ask about smoking habits though, because they start with the premise that there is a link and work backward from there. Then, based on post hoc ergo proctor hoc (one thing happened after another thing, therefore the first thing was the cause of the second thing) we have proof that smoking causes everything that can kill you.
Again, it's not that simple. If you have a Type A personality you are both more likely to have heart disease and more likely to smoke; if you are from a low socio-economic background you are also both more likely to have heart disease and more likely to smoke, but where is the cause and effect? Is it the personality type, the smoking or the socio economic factors that causes heart disease? Or is it some complex interaction between them? The truth is that we do not know.
Pancreatic cancer, as another good example, has a statistical link with smoking that no one has been able to find a definitive medical basis for. There are a number of theories around poisons ingested through smoking, but they are all based on the idea that there is a statistical link so let's find the reason for it. Pancreatic cancer also has a statistically significant link with being tall. I am not making this up, google it yourself. You are significantly more likely to get pancreatic cancer if you are tall. No one knows why, but it is quite acceptable to say that we don't know the reason but there is no medical basis for thinking that being tall, on its own, causes cancer therefore it must be a correlating factor not a causative one. Not so with smoking, of course, that must be significant because everyone knows that smoking is the cause of all disease.
The other thing that is not widely known about epidemiology is how much of a correlation is required to prove a cause and effect link. Lies, damn lies and statistics, eh? If you smoke you are 2,400% more likely to get lung cancer than you are if you don't smoke. 2,400% - that's a lot. However another way of describing these statistics is to say that if you smoke you have a 99.8% chance of not getting lung cancer. The actual numbers? In 100,000 smokers, 160 of them will get lung cancer, whereas only 70 out of 100,000 non-smokers will. Lung cancer is pretty rare, no matter how risky your behaviour. Beware of any report that only talks in percentages and doesn't give you the actual data as well.
Epidemiology is inherently unreliable; statistical bias and confounding factors can skew the results and prove a link where none exists. The National Cancer Institute of America recognises this and says that a relative risk of at least 2 is the minimum to prove a significant link. You would think that this requirement from a prestigious body would have some force, right? Not so. The World Health Organisation conducted a study of passive smoking that found a relative risk of 1.17 for lung cancer in non-smoking co-workers of smokers. This was trumpeted around the world as proof that passive smoking increases your risk of lung cancer by 17%. No one pointed out that this was absolute bollocks. No one.
There is a huge difference between relative risk and absolute risk. Based on the lung cancer data above, your risk of getting lung cancer as a non-smoker is 0.07%. If the WHO is correct and your relative risk is 1.17 because you work with a smoker, your absolute risk of getting lung cancer rises to 0.08%. Statistically, your increased risk of death is less than your risk of dying in a high school football game or a vicious pig attack. I didn't make this up, and it was noted in the report itself that "the increased risk is not statistically significant" (Journal of the National Cancer Institute, October 1998), and yet this report is quoted as one of the studies proving a link between passive smoking and lung cancer. It's quite hard to fathom that prestigious organisations carry on this way and maintain their credibility.
However, lets move on to studies that do show a statistically significant link between smoking and disease. Again, on the surface it's proof, but scratch the surface a little and it is not always reliable. There is a significant statistical link between smoking and cervical cancer. There is also a statically significant link between being a prostitute and getting cervical cancer. Neither of these facts means that smoking or prostitution causes cervical cancer. We now know that the most common cause of cervical cancer is the human papilloma virus. Being a prostitute means that you are more likely to be exposed to the virus and that you are more likely to smoke, but smoking itself is not the cause of the cancer. Despite this relatively recent discovery, anti smoking literature still blames an entirely arbitrary 13% of all cases of cervical cancer on smoking.
It puzzles me though, that so many of the studies I looked at started with the assumption that any statistical link between smoking and a disease is a causative one, not merely a correlation. We have a link, therefore we need to find a reason for it, so keep going lads, you'll come up with something if you try hard enough!
Having said all that, there are some diseases where smoking as a risk factor has a genuine medical basis, not just a statistical one: emphysema, high blood pressure and heart disease being the main ones. Heart disease is one of the leading causes of death in first world countries so let's take a closer look at that.
The best medical information we have at the moment shows that nicotine speeds up the heart, raises blood pressure (aka hypertension), and constricts the arteries throughout the body. Carbon monoxide (one of the many chemicals ingested through smoking) robs the heart of its oxygen supply and, combined with nicotine, increases blood clotting and clogging. Thus we postulate that smoking can lead to heart disease and early death.
However, again, even if this is absolutely true, it is not as simple as it appears on the surface. The human body is a marvellously complex machine; it is designed to heal itself and resist damage to all its functions. So you can indulge in behaviour that damages your heart (such as having your husband jump out from behind the couch and frighten 10 shades of shite out of you) but your heart and cardiovascular system will heal itself (although your husband may not) and continue on its merry way until you get too old to be able to heal anymore and you die.
Apart from just getting too old, there are other things that will stop your body healing itself, or will cause so much damage that it is simply unable to do so, and this is where we come back to risk factors. Smoking, excessive drinking, poor diet, stress, childhood circumstances, genetic predispositions, excess body fat and personality type are all significant risk factors for damage to your heart and cardio vascular system that your body cannot heal on its own. While these risk factors are fairly well understood, what is not well understood is the complex interaction between them.
If you put me (38 year old female smoker with no family history of heart disease, an ok diet, not quite enough exercise, low cholesterol, have been known to have more than 2 standard drinks in a night, type A personality and a normal BMI) in a room with Man X (40 year old male non smoker, a family history of heart disease, non drinker, good diet, slightly high cholesterol, regular exercise, Type B personality, incipient pot belly) which one of us would have a higher risk of heart disease? Well, even with all that information, no one could give you the answer. Both of us have some high risk factors and some low risk factors.
Do I have no family history of heart disease because my entire family died of malaria before heart disease manifested itself? How long have I had an ok diet? Did I eat well as a child? Was I exposed to lead paint, significant amount of pollution or chemically grown foods as a child? How long have I not been exercising? How often do I drink too much? How long have I been drinking too much? Will I stop before I'm 40? How long have I smoked? How much do I smoke? How will this change over time? How does my genetic makeup react to all these risk factors? Is my DNA easily unravelled or is it incredibly robust? How do these answers compare to Man X? What is the trade off between my low cholesterol and my smoking? If I grew up in the country, eating fresh food and breathing clean air, will that protect me from the effects of being a smoker now? Am I less at risk because I live in Melbourne, where the air is relatively clean, than Man X who grew up in Beijing breathing fetid air during his formative years?
Well, I'll be able to tell you the answer definitively in about 50 years when Man X and I will both be dead and statisticians can slot us into the appropriate category. Right now, all we know is that I am at risk because I smoke and he is at risk because of his family background.
Which brings us to another favourite term in the anti smoking literature. Preventable death. Man X cannot do anything to alter his family background. DNA is, at the moment, immutable. I can do something about my risk factors - I can stop smoking. Within a few years this will probably reduce my risk to near the same level as a non-smoker. Therefore if I continue to smoke and end up dying of heart disease at 70 it was a preventable death because without my increased risk factor I could have lived to 80. If Man X dies of heart disease at 70 this was presumably not a preventable death because he could not alter his genetic predisposition to heart disease. The logic is irrefutable.
Over the last century life expectancy in first world countries (excluding indigenous populations of course, but that's a discussion for another time) has increased somewhere between 20 and 30 years. It is also the first time that I know of that it has become morally reprehensible not to aspire to longevity. In Roman times, medieval Europe, pre-Columbian North America, pre-industrial Japan and China death was so prevalent and inexplicable that fighting against it was pointless. Either you lived or you didn't. Now, for the first time in human history, we do not expect to die young at the hands of capricious fate. For the first time we have the concept of preventable death. And we're pissed about it. Why? Why is it not ok to live as we choose rather than as long as we possibly can?
For the first time just the idea of dying young(ish), from any cause, is anathema. We do not choose to die for honour, principles, religion or because our ant overlords ordered us to, we think people who do so are insane. And people who choose a lifestyle that may lead to early death are not much better.
I have no desire to die young, I have two children, a lovelyhusband and a very entertaining life, I'd like to be around to enjoy those things for some time yet. I do not however, aspire to 15 years of dementia in a nursing home, unable to recognise anyone I used to love and having some kind nurse change my nappy for me. Longevity alone is not an ambition. Quality of life is.
I enjoy smoking; it has many benefits that are now verboten to discuss. It acts as an anti depressant, it increases alertness and cognitive function, it is a social bond and an enjoyable pastime. All these things are beneficial to health and longer life. I accept that the trade off is that it increases my risk of suffering many diseases, but this is a fully informed choice I have made for myself and I am concerned about the rights of government and society to impinge on my ability to make that choice. And it is a slippery slope. Where do we go from here?
Apparently the next step in anti smoking measures is being discussed by the same panel that bought us no smoking in indoor public areas. On the table is requiring all GPs to provide smokers with anti smoking literature at every visit, banning smoking in outdoor public areas, banning smoking inside private homes, banning depictions of smoking in film and theatre, and, my personal favourite, requiring smokers to have a licence before they can buy cigarettes.
I know the anti smoking lobby justifies the legislation against smoking with the idea that second hand smoke is dangerous, but this really is complete rubbish. Let me give you some examples to add to the WHO idiocy outlined above. Dr James Enstrom conducted a study of 35,000 Californian non-smokers married to smokers to establish whether passive smoking has any long-term health effects. This is not dodgy science cooked up in Phillip Morris' backroom, the data was provided by the American Cancer Society and the study was peer reviewed and published in the British Journal of Medicine. Dr Enstrom found absolutely no link between second hand cigarette smoke and long term health problems. There are dozens of other studies that have had the same results, and virtually none, where the science is robust, to prove that second hand smoke is dangerous.
However, justified or not, the anti smoking brigade have pretty much won the war on tobacco and now they turn their attention to alcohol and the obesity crisis. 20 years ago we were talking about banning cigarette ads, now we are talking about banning junk food ads. All well and good you say, our children should not be exposed to that kind of pressure. I could almost agree, but what happens in the next 20 years?
Dr Majid Ezzati, Associate Professor of International Health Harvard University claims that diabetes is already a higher risk factor for early death than smoking is, I suspect that very soon diet will take over from smoking as the cause celebre for self important interest groups, but what are they going to do about it? You can't ban people from eating can you? So, do you legislate an exercise requirement? How do you enforce it? Or do we just ban all forms of junk food? That's going to put a bit of a kink in the economy, but it's all perfectly justified if we gain another generation of befuddled octogenarians, right?
I rather like to sit down occasionally with a book, a glass of wine and a Tim Tam. What is going to happen to that in 20 years time? Will I need to get a licence to buy chocolate? If I exceed my quota, will I be able to get some chocolate-coated biscuits on the black market? Sounds ridiculous, right? I agree, but if we have decided that rational adults are no longer able to make their own decisions about physically hazardous behaviour, where do you draw the line? Is it with active behaviour? Or do we start on hazardous passive behaviour as well? And who gets to decide where the line of demarcation is?
I'm like a broken record aren't I? It's not simple, there are no easy answers and the causes and effects are far too complicated to propose a simple or definitive solution. Governments and lobby groups would far better serve their cause and the interests of a free society by allowing a rational and informed debate on this, or any other, issue than this hysterical insistence on banning free choice and then justifying it with junk science.
The truth is that, no matter how much I might wish it isn't so, smoking is indisputably going to increase your chances of preventable early death, we just don't know by how much, how preventable your death will be and how much earlier you will die because of it.
However, despite all my disagreements with the way the smoking issue is dealt with and no matter how much I might wish it isn't so, smoking is indisputably going to increase your chances of preventable early death. We just don't know by how much, how preventable your death will be and how much earlier you will die because of it. All you can do is make a fully informed decision, be prepared to change your mind as more facts come to light and never ever accept statistics at face value.
Read In Defence of Smoking - Part I
References
Joe Jackson was my first inspiration for this piece. He published a gracefully written and well thought out piece about smoking that, while I believe it garnered him a huge amount of hate mail, is well worth a read.
http://www.joejackson.com/smoking.php
McNeill "Smoking and mental health - a review of the literature" St George's Hospital Medical School London, Action on Smoking and Health.
http://old.ash.org.uk/html/policy/menlitrev.html
James "Why I'm still dying for a cigarette" The Observer 29/12/2002
http://www.observer.co.uk/focus/story/0,6903,866130,00.html
Environmental tobacco smoke does not affect mortality
http://www.bmj.com/cgi/content/full/326/7398/0
Glassman AH, Stetner F, Walsh BT et al. "Heavy smokers, smoking cessation, and clonidine. Results of a double-blind randomized trial."
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3367452&dopt=Abstract
Berlin I, Spreux-Varoquaux O, Said S, Launay JM "Effects of past history of major depression on smoking characteristics, monoamine oxidase-A and -B activities and withdrawal symptoms in dependent smoker" Department of Clinical Pharmacology, Hopital Pitie-Salpetriere, Paris, France. Drug Alcohol Depend 1997 Apr 14; 45(1-2):31-7
www.biopsychiatry.com/smoking.htm
Why most medical research is false
http://medicine.plosjournals.org/archive/1549-1676/2/8/pdf/10.1371_journal.pmed.0020124-L.pdf
Smoking and heart disease
http://www.americanheart.org/presenter.jhtml?identifier=4726
There is a lot more. I'm still trying to collect all the scraps of paper and emails I sent myself. Stay tuned.
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