It was reported this week that 3,726 lives [were] saved by introducing the smoking ban in 2004.
This is due, we are told, to the absence of second hand smoke in public places. At first glance this seems to be a positive development but such a stunning success surely deserves a closer look, if only to discover how we got something so right for once.
Explaining the study and its methodology, Dr Luke Clancy, former chairman of ASH Ireland, warned that it was “complex” and indeed readers can log on and read the full complexity at the PlosOne website. While it is not easy fodder it includes a simple graph that would appear to dramatically undermine the findings of the study.
The graph shows that since the introduction of the smoking ban in 2004 rates of heart disease, strokes and, to a lesser extent, cancers have been falling steadily over nine years. But it also shows that this was the case in the twelve years leading up to the ban. It clearly demonstrates that, ban or no ban, death rates from those three illnesses were falling anyway. One can speculate that better medical interventions and treatments are responsible for this, along with greater awareness of health among the general population.
The government body responsible for compiling the official statistics, the Central Statistics Office, shows that, year-on-year, we are living longer. So the reported drop in the most common diseases, as reported in this research, fits perfectly with the real facts on the ground.
Where the research departs from the facts is when they attribute this natural fall to the absence of ‘second hand’ smoke. Complex conditions such as heart disease, strokes and cancers are multifactorial. That is, it is very difficult to attribute the disease to any one factor. Contributing causes may be stress, alcohol, diet, lack of exercise, hereditary reasons, viral infections and smoking, amongst others.
For this research to have any validity then all other contributing factors must be ignored. Added to that, the natural falls in the various named diseases before 2004 must be ignored too. The research does not explain why, when public areas were full of tobacco smoke before 2004, rates for heart disease, strokes and cancers were already falling.
Neither does it address any of the other contributing factors, many of which have been positively addressed in the last 20 years. It dismisses better overall health education and awareness, improved interventions and treatments and chosen healthier lifestyles in favour of demonising smokers. As such, it appears selective and skewed. A cynic could accuse the authors of beginning with a conclusion and looking for the proof.
Chris Snowden, head of the Lifestyle Economics Unit at the renowned Institute of Economic Affairs in London, has already commented on this study on his blog. The online magazine Spiked published an article on studies similar to this one and it illustrates the difficulty with this kind of investigation.
There are some other interesting facts to ponder. Dr Clancy’s study is an epidemiological study and the first law of epidemiology is that while it may show correlation it doesn’t show cause. Yet in this instance he claims to have discovered cause. The Central Statistics Office doesn’t list a single death from passive smoking in this country, nor has any other country officially listed it as a cause of death. It seems strange to claim that almost 4,000 lives have been saved by the absence of ‘passive smoke’ when it cannot be proved that anyone died of passive smoking in the first place.
The largest study ever on passive smoking and its effects was conducted by Dr Enstrom & Dr Kabat and published in the British Medical Journal in 2003. They studied 118,000 people over a 39-year period and analysed exposure to second hand smoke relative to heart disease, lung cancer, and chronic obstructive pulmonary disease. The study failed to find any significant link between passive smoking and these three conditions.
Another problem with Dr Clancy’s study is this. When research like appears in the public domain we have to ask, why were mortality rates falling long before the smoking ban and why hasn’t its introduction made them fall more dramatically? Were we simply getting things right all along without any help from the nanny state?
I would suggest that politicians take this study with a pinch of salt but, some might argue, that might be bad for you too.