Sunday 27 November 2011

The failure of the Scottish smoking ban

A new study in PloS has found that Scotland's smoking ban had no effect on the country's smoking rate in the long term. Authored by the notorious Jill Pell and colleagues from Glasgow University, the study shows that there was an upswing in quit attempts in the months before and after the implementation of the ban (March 2006), but that these attempts had no lasting effect on smoking prevalence.

The graph below, which comes from the PloS study, shows 12 years of smoking prevalence data. The dotted line shows the predicted rate based on past performance. The vertical line shows the smoking ban.

If you look closely, you can see that smoking prevalence dropped below the anticipated level for a while around the time of the ban, but then rose back to the normal level where it has remained ever since.

... in October–December 2005 immediately prior to the introduction of the ban prevalence fell by 1.70% more than expected from the underlying trend. The magnitude of the decay parameter, −0.08, (95% CI −0.38, 0.22) indicates that this effect was short lived with prevalence returning to its long term trend by the last quarter of 2006.

The graph below shows the quantities of nicotine replacement therapy (NRT) being handed out by the Scottish NHS between 2003 and 2009. Again, the dotted line shows the predicted figures.

Assuming that NRT prescriptions are a marker for total quit attempts (a reasonable assumption), there was a rise in people trying to give up around the time of the ban. Quit attempts then fell below the average for the next two years. This suggests that many of the people who would have made a quit attempt in 2007 or 2008 brought their attempt forward to late 2005/early 2006. Having failed to quit at the time of the ban, these people did not try again in the next couple of years. Over the whole period, there was no increase in the number of people who tried to quit.

The rise in quit attempts was no doubt bolstered by the publicity about the ban and the expensive smoking cessation campaigns that accompanied the legislation. As the study's authors note:

In the six months leading up to implementation of the legislation there were two high profile television campaigns.

It was not the ban, but the fear of the ban, combined with increased advertising for smoking cessation services, that led to the increase in quit attempts—this is evident from the fact that the 1.7% drop in smoking prevalence pre-dated the ban by several months. Contrary to the expectations of anti-smoking lobbyists, the ban itself did not help people sustain their quit attempts, nor did it have any independent effect on the smoking rate. Given the choice of giving up smoking or giving up the pub, many of them gave up the pub.

Despite a large surge in the amount of NRT being distributed, there was no lasting effect on smoking prevalence. The short term blip was not sustained in the medium- or long-term. Ultimately, the ban failed to achieve what its advocates hoped and predicted. It also suggests that NRT products are not very good at helping people quit for more than a few weeks or months.

This should all be contrasted with the claims put forward before the ban. In 2005, NHS Scotland's 'evidence-based' review of the literature found that:

Prospective cohort studies reported reductions in smoking prevalence of 7–20% and population-based studies comparing workplaces with and without restrictions showed 15–20% lower prevalence. Partial restrictions had little or no effect. A recent meta-analysis reported a 3.8% reduction in absolute prevalence (pooled effect) associated with smoke-free workplaces.

Given the uncertainty around the precise estimate, the benefit of reduced smoking prevalence has been estimated using conservative estimates of the effect, with a range of 1–3%.

A more conservative estimate would have been 0%. It would have been right.

And let us cast our minds back to 2006 when the BBC reported this breathless forecast from Scotland's Chief Medical Officer...

Ban will 'eradicate lung cancer'

Lung cancer could be virtually wiped out in Scotland as a result of the smoking ban in public places, according to the chief medical officer.

Dr Harry Burns said lung cancer rates would be reduced to just a few hundred cases a year in the future.

Dr Burns said: "Imagining Scotland with no lung cancer is not trivial speculation. In the 1960s, one in 100 men died of lung cancer. Today, rates are falling all the time and thanks to the smoking ban, I expect the reduction in deaths to accelerate until dying from the disease becomes a rare occurrence.

"Anecdotal evidence shows that since the smoking ban, there has been a surge in the numbers of smokers seeking help to give up."

We now know that this "surge" was a temporary blip which was followed by two years of fewer people "seeking help to give up." It turns out that Imperial Tobacco was better at predicting the future than Harry Burns. This, also from 2006...

Imperial not worried by smoke ban

The world's fourth-largest tobacco group, Imperial Tobacco, has said it does not expect UK smoking bans to have a significant impact on business.

"We believe [UK] smokers will continue to choose to smoke regardless of regulations and our view is supported by experiences in other markets," said Imperial.

Can we expect a mea culpa from the anti-smoking campaigners who predicted a huge drop in the number of smokers, if not the elimination of lung cancer? Can we expect them to reassess their strategy in the light of yet another broken promise?

We cannot. As I have said many times, tobacco control is not a results-driven business. As in Ireland, where the smoking rate is now higher than before the ban, the anti-tobacco industry has only one response to failure—more of the same. Pell et al's conclusion epitomises this mindset.

Quit attempts increased in the three months leading up to Scotland's smoke-free legislation, resulting in a fall in smoking prevalence. However, neither has been sustained suggesting the need for additional tobacco control measures and ongoing support.

Heads, we win. Tails, you lose.


Bill Gibson said...

These results from Prof Pell also confirms once and for all that her claimed 17% Reduction in Heart Attack Admissions was false. Maybe a nudge to Debs Arnott and Sheila Duffy is required as they still push the lie at every opportunity.

Xopher said...

In addition to all the above damning evidence it should be remembered that NRT was not always easily available.
'Legislation' in 2001/2 was passed to provide greater access to NRT but, try as I might, I can't see any evidence of this affecting the long-term steady decline in smoking prevalence.

Well worth reading at the dormant Nearlydone site is the Memorandum to the Health Committee by Professor Scruton, according to ASH(but no longer on ASH website!), "high priest philosopher of the libertarian right defrocked and exposed as grimy hack for tobacco industry"

Even the most unprincipled Arthur Daley couldn't stoop to the depths of Tobacco Control.

Anonymous said...

I don't know that Tobacco Control will be bothered about these figures. As I understand it, they have very long-term objectives (which keeps them in jobs ad inf!).

Whatever one says about variations in the graph, on the whole the smoking trend is downwards. ASH ET AL would say that this is precisely their objective. All the rest, heart attacks etc is mere noise, and they do not care whether it is true or not.

The probability is that a halt in the massive waste of resources will only be called when the natural law of 'diminishing returns' takes effect. Already, it is clear that plain packaging and horrible pictures on cigarette packets is going to be a massive failure. What is the phrase? Oh yes...'familiarity breeds contempt'. Another is the plan to make cigarettes go out if left unattended. I think that Spain is already experimenting with this, and, to be honest, as a smoker, I do not mind that! Re-lighting a fag is no trouble at all and fags last longer! What is the problem? Also, as we all know, ever increasing prices and taxes on tobacco create a black market of tax free products. It must be so. Also, not only tobacco can be smoked! There are many alternative materials which are 'smokable', as the American Indians knew.

What to me is horrific is the compliance of MPs.

Anonymous said...

These PLoS study figures appear not to agree with a report last week which stated that smoking prevalence in Scotland had increased to 25 or 26% (can't remember exactly).

Anonymous said...

Further to my comment above:

Dr Evil said...

The ban will not eradicate lung cancer as smoking is only a contributory factor and then only for a subset of smokers. There will always be some who have genetic predisposition to small cell lung cancer anyway. Genetic diversity.

Anonymous said...

'Lung cancer could be virtually wiped out in Scotland as a result of the smoking ban in public places, according to the chief medical officer."

Of course, no reason or proof is given.

But here:

Cigarette Smoking Among Adults --- United States, 2006

In 2006, an estimated 20.8% (45.3 million) of U.S. adults were current cigarette smokers

Table 2 tells us that current smokers account for 20.9% of the cases of lung cancer.

Soooo, the 20.8% of adults that are current smokers account for 20.9% of the lung cancers!!!

Obviously, smoking 'causes' lung cancer and doing away with smoking will do away with lung cancer.

Welll, 20.9% anyway. :)

Gary K.

Christopher Snowdon said...


We've been through this before, I think. Many people give up smoking when diagnosed with lung cancer and people who are ex-smokers are are greater risk of lung cancer. The relevant comparison is ever-smokers vs never-smokers.

Anonymous said...

Dear Sir,
With ALL due respect.

1)"Many people give up smoking when diagnosed with lung cancer."

If you have data on that, I would like to see it. The data I have found shows that there were 44.4 million ex-smokers(USA) in 1990 and 48 million in 2006. This indicates that about 90% of them quit at least 15 years ago. Quitters of over 10-15 years have about the same risk for lung cancer as never-smokers. Otherwise,why quit?

2)" ex-smokers are are greater risk of lung cancer"

70% of lung cancers occur over the age of 65 and about 33% of ex's are aged 65 or older. Current smokers and never-smokers are about 7-8%.

The true comparison would be between smokers(current+ex's with similiar risk) and non-smokers(never+ex's with similiar risk).

Gary K.

Christopher Snowdon said...

The source you give shows that 49.8% of the population have never smoked and 17.9% of lung cancer cases are never-smokers. To put it another way, 82% of lung cancer affects the 50% of the population who has ever smoked.

I'm not very interested in getting into the 'does smoking cause lung cancer?' debate again. Any evidence you have which overturns the consensus view should be sent to the tobacco industry who, I'm sure, will be delighted to receive it.

Anonymous said...

OK, you do not have to comment on my posts.

As for the 'consensus view'; do you mean, like the 'consensus view' that smoking bans cause a immediate reduction in heart disease hospital admissions? :)

And yes, I do have a streak of 'smart ass' in me. :(

Gary K.

Christopher Snowdon said...

Right, but I'm not saying it's correct because it's the consensus view. It's correct because virtually every piece of evidence supports it. The fact that some other popular beliefs might be wrong does not alter that in any way.