Smoking, COVID-19 and Mendelian Randomisation

It's been interesting to watch how the Guardian has been covering the research into smoking and COVID-19. Like many media outlets, they reported the news last spring that researchers had found an inverse association between smoking status and Covid-related hospitalisations and that work was underway to see if nicotine patches would help people recover from the disease. 

Since then there have been many more relevant studies published which the Guardian has ignored, possibly because they nearly all show that smokers are less likely to be infected with the virus than non-smokers. 

It has only revisited the topic twice. The first was when some researchers in San Francisco did some modelling and claimed that smokers (and vapers) were more 'medically vulnerable' to COVID-19. The second was when a study was retracted because of undisclosed 'links to the tobacco industry'.

In the meantime, there have been six editions of a comprehensive meta-analysis, the last of which looked at 87 studies and concluded that smokers are 33% less likely to be infected with the coronavirus, no more likely to be hospitalised with Covid than non-smokers and no more likely to die from Covid than non-smokers. 

The Guardian is not alone in ignoring all this research. Hardly anybody in the media has touched the issue for over a year. But the Guardian is back today with a new story...

Smokers up to 80% more likely to be admitted to hospital with Covid, study says

Smokers are 60%-80% more likely to be admitted to hospital with Covid-19 and also more likely to die from the disease, data suggests. 

 A study, which pooled observational and genetic data on smoking and Covid-19 to strengthen the evidence base, contradicts research published at the start of the pandemic suggesting that smoking might help to protect against the virus. This was later retracted after it was discovered that some of the paper’s authors had financial links to the tobacco industry.

The unwary reader might assume from this that only one study has suggested that 'smoking might help to protect against the virus' and that this study was retracted. This is untrue. Dozens of studies have come to that conclusion, including in top journals such as the NEJM, Nature and the Lancet, and the one that was retracted was not published 'at the start of the pandemic'. (It is also important to note that it was not retracted because there was anything wrong with it; only that the journal has a policy of not publishing research by anyone with 'links' to tobacco.)

The new study uses Mendelian Randomisation which looks at the health outcomes of people who have certain genes. In this instance, it looks at people who have a genetic propensity to smoke. Apparently these people were more likely to be hospitalised with Covid, although the authors acknowledge that a genetic propensity to smoke may also correlate with a more general propensity to take risks with one's health such as ignoring social distancing guidelines. 

Mendelian Randomisation can be a very useful tool, but it has so far been shown to be weak at best and misleading at worst when it comes to lifestyle-related diseases. The obvious problem is that people who have genes which give them a propensity to do something do not necessarily do it. This is a particular problem when it comes to smoking because people's propensity to smoke has been severely curtailed by decades of public education, stigmatisation, high taxes and so on. 

Consequently, MR studies have found a link between smoking and lung cancer, but the association is much smaller than that found in observational epidemiology. In MR studies, it barely doubles the risk whereas smoking increases the risk by a factor of 10 or 20 in reality. If you take these studies seriously, smoking doesn't increase the risk from most cancers at all and only mildly increases the risk from a few others. (I have written about this before.)

MR research into alcohol has also been near-useless. MR studies have been cited as evidence that moderate drinking doesn't reduce the risk of heart disease (in contrast to many dozens of epidemiological studies which show that it does), but it is an inconvenient fact that MR studies don't show any risk from drinking either. An MR study published last year failed to find any statistically significant link between drinking and any disease except, bizarrely, lung cancer.

The methods are simply too blunt to find anything other than the strongest associations (smoking and lung cancer being the obvious example). Advocates of MR in lifestyle research claim that it cuts out confounding factors, such as socio-economic status, but it has a much bigger problem in that it incorrectly identifies people as smokers or drinkers when they are not. 

“The study adds to our confidence that tobacco smoking does not protect against Covid-19, as their Mendelian randomisation analyses are less susceptible to confounding than previous observational studies,” wrote Dr Anthony Laverty and Prof Christopher Millett of Imperial College London in a linked editorial published in the journal Thorax.

This is activist-driven spin (we have encountered Christopher Millett before and the editorial in question openly calls for more 'tobacco control' policies). The obvious point is that if smokers were 60-80% more likely to be admitted to hospital with Covid, we would see evidence of it in the hospital admissions data. But we don't. Time and time again, we find that smokers are less likely to be admitted to hospital with Covid. 

MR studies take a bit of work for journalists to get their heads around and the studies themselves rarely provide enough information for the reader to see what is going on. In this instance, as with the moderate drinking issue, MR seems to have been wheeled out to contradict findings that are inconvenient for the 'public health' lobby rather than to provide illumination.

The study also contains some observational epidemiology. The number of smokers in this part of the study is suspiciously small. Only 3.3% of the sample confess to smoking (the national rate is 14%). This may reflect the demographics of the kind of people who sign up for these things, or it may reflect undisclosed smoking, or both. Whatever the reason, the researchers still found that smokers were less likely to be infected with Covid, with heavy smokers being half as likely to be infected. You have to go to the supplementary tables to discover this. The authors do not report it in the text.

The idea that smokers are more likely to suffer more from COVID-19 if they get it is, of course, very plausible. Nearly all the evidence shows that former smokers are more likely to be hospitalised with Covid, presumably because they are more likely to have pre-existing health conditions.

The question is whether smokers are less likely to catch the virus in the first place. And if they are, why? If they aren't, why do antibody tests of whole populations (before vaccination campaigns began) find that smokers are less likely to have antibodies, i.e. they are less likely to have been infected? 

Confounding factors cannot be blamed for this and a study which combines the MR method of assuming somebody is a smoker based on their genetic profile with an observational element based on a sample that is clearly not representative of the public at large and contains hardly any smokers does not give us a compelling answer. Nor, if this study is correct, does it explain why all the other studies are wrong. 

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Idiotic sugar reduction scheme spreads to Europe

The UK's hopeless sugar reduction scheme is spreading to Europe thanks to the equally hopeless WHO. 

I've written about it for The Critic...

If you want to know what the new, outlook-looking, post-Brexit, global Britain is all about, the Department of Health dropped a clue this week. In a punch on the nose for embittered Remoaners, it announced that the UK “has been chosen by the World Health Organization (WHO) to lead a new Sugar and Calorie Reduction Network to take global action on sugar and calorie reduction.” In a press release, the Department of Health mentioned twice that the WHO’s EU region “covers around 50 countries” and has “a much wider reach than the European Commission’s remit.” In your face, Eurocrats!

The UK has been selected because of its “world-leading expertise in domestic sugar and calorie reduction”. The UK may be one of the fattest nations in Europe, but thanks to the nearly-dead Public Health England it “has seen good progress with its sugar reduction programme — with sugar reduced by 13 per cent in breakfast cereals, yogurts and fromage frais”. Swarthy foreigners are naturally eager to emulate this triumph and they kneel at our feet awaiting instruction. They, too, want to make chocolate bars slightly smaller and corn flakes less tasty.

“Today’s announcement puts into action the UK’s ‘Global Britain’ ambitions”, said the Department of Health, presumably with a straight face. The scheme will be run by the new Office for Health Improvement and Disparities which opens for business at the start of next month as the replacement for Public Health England. If there was any doubt that the Office for Health Improvement and Disparities would be Public Health England with new stationery, it has been confirmed by its embrace of this dog’s dinner of a policy.

Do read it all.

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Lowering the drink-drive limit didn't work in Scotland

My City AM column today is about the way governments prefer legislating to governing...

In December 2014, Scotland introduced a new policy modifying its drink-drive limit, to reduce the number of alcohol-fuelled traffic accidents. The legal limit was slashed from 80 to 50mg per 100ml of blood. Now, seven years later, a study published in the Journal of Health Economics has looked at the impact of the policy. The results are perhaps surprising.

Do have a read.

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How a typo tricked the media: half a beer a week won’t harm your health

First published in Spectator Health in February 2017

Eggs were on faces yesterday after some astonishingly bad science reporting in sections of the media. In articles that have since been taken offline, the Telegraph and Mirror announced that half a pint of beer a week is sufficient to harden the arteries and cause heart disease. Given the almost homeopathic quantities of alcohol involved — not to mention the fact that moderate drinking is known to reduce heart disease risk — this was a rather surprising finding, but it had supposedly been published in the Journal of the American Heart Association and was therefore considered legit.

Alarm bells started ringing when the Telegraph came up with this eyebrow-raiser:

‘The UK study defined consistent long-term heavy drinking as equivalent to drinking one serving of alcoholic spirit, half a pint of beer or half a glass of wine per week.’

The idea that drinking half a pint of beer once every seven days constitutes ‘long-term heavy drinking’ is patently ludicrous. There are some strange ideas floating around in the world of ‘public health’ these days, but things are not quite that mad. You have to wonder how that sentence got written, let alone approved and printed, without somebody at the Telegraph saying ‘surely that can’t be right’?

The rest of the story hinged on this basic error. The study itself is pretty good. Its authors set out to see whether heavy drinking stiffens people’s arteries, because arterial stiffness is a predictor of cardiovascular disease. They used a database of civil servants stretching back to the 1980s and measured something called pulse wave velocity (PWV) to gauge the state of their arteries. The higher the number, the harder the arteries.

The authors note that previous research has found the relationship between PWV and alcohol consumption to be J-shaped, which is to say it is relatively high for non-drinkers, lower for moderate drinkers and high again for heavy drinkers. This is significant because the relationship between cardiovascular disease and alcohol consumption is also J-shaped, ie moderate drinkers have a lower risk than both those who abstain and those who drink heavily.

The authors set out to test this and succeeded. Defining heavy drinkers as anyone who consumed more than 14 units a week, and measuring in metres per second (m/s), they found PWV levels among men of 8.8 m/s for non-drinkers, 8.3 m/s for moderate drinkers and 8.7 m/s for heavy drinkers. Among women the readings were 8.6 m/s, 7.9 m/s and 8.3 m/s.

Over the years, the PWV levels rose, but it was the non-drinkers and ex-drinkers who saw their levels rise the most. By contrast, the authors note that ‘stable moderate drinkers have the lowest PWV values throughout the study period’.

This seems to confirm the J-curve, but how does it support the claim that drinking half a pint a week gives you heart disease? It doesn’t. The study found the exact opposite of what the Telegraph and Mirror claimed. It showed that moderate drinkers, including those who limit themselves to a swift half once a week (if such people exist), have a lower risk of heart disease than those who never drink at all. So how did the press get it so wrong?

If you are going to rely on reporting science by press release, you have to be confident in the press release. Unfortunately for the fourth estate, this one was a stinker. The study’s authors defined anyone who drank more than 112 grams of alcohol a week as a ‘heavy drinker’. There are eight grams of alcohol in a unit, therefore they were drinking more than 14 units, but when the press release tried to explain this, it all went wrong:

‘Consistent long-term, heavy drinking was defined in this UK study as more than 112 grams (3.9 ounces) of ethanol per week (roughly equivalent to one serving of alcoholic spirit, half a pint of beer, or half a glass of wine); consistent moderate drinking was 1-112 grams of ethanol per week.’

The first part is true and so is the last bit. It is the middle section that’s the problem. 112 grams is by no means ‘roughly equivalent to one serving of alcoholic spirit… [etc]’. It is 14 servings of alcoholic spirit. I can’t be sure how this error crept in. My hunch is that whoever wrote it meant to put ‘eight grams of ethanol is…’ just before ‘roughly equivalent…’, but failed to do so.

Whatever the reason for this slip, it was dutifully repeated by sections of the media and the bizarre notion that ‘long-term heavy drinking’ is defined as one unit a week was born. And since the study found that heavy drinkers have harder arteries, this turned into ‘Just half a pint of beer a week increases risk of heart disease — new study’ (you can read the now deleted Telegraph article here thanks to the Wayback Machine).

I hesitate to call anything a new low in health reporting but this is definitely in the same postcode as the nadir. I think there are two lessons that can be learned from it.

Firstly, if proof were needed that some reporters do not read the research they write about, this is it. It is glaringly obvious that the journalists in this instance did not give so much as a cursory glance to the abstract, let alone to the tables. This is worth bearing in mind next time you read a health report in a newspaper.

Second, it says something about the outlandish claims made by ‘public health’ academics that a journalist would find it perfectly believable that they have not only started to define ‘heavy drinking’ as one small drink a week, but that they view this as a potentially lethal dose.

Daft as this may seem, it has to be put in the context of previous assertions by the ‘public health’ lobby which have been accurately reported under such headlines as ‘Cancer risk of two beers a year’, and ‘No safe level of drinking, health chiefs warn’. If you spend your working hours reading press releases from people who think that roast potatoes and buttered toast are the new asbestos, it can’t be easy to separate fact from fantasy.

The Telegraph and Mirror did such a bad job of reporting this particular story that they made the rest of the media look like Pulitzer prize winners, but the truth is that everybody covered it pretty badly. The Sun ran with ‘Men who drink ONE pint a day are “increasing their risk of having heart disease or a stroke”‘ and the Daily Mail went with ‘How just one pint a day can increase the risk of heart disease by prematurely ageing the arteries’.

While both newspapers avoided the ‘half a pint a week’ booby trap, they used the lightest of ‘heavy drinkers’ as their example to make a claim that is not supported by the study. On average, the people in the study who drank more than 14 units a week had stiffer arteries than those who drank less, but averages can be misleading. There is nothing in the data to suggest that 14 units is the threshold at which risk increases. It could be 30 or 40 units for all we know.

More importantly, every newspaper ignored the crucial finding that the heavy drinkers only had an ‘increased risk of heart disease’ if you compared them to moderate drinkers. It was the non-drinkers – both ex-drinkers and lifelong teetotallers — who had the stiffest arteries of all.

This is biological evidence which supports the enormous quantity of epidemiological evidence showing the benefits of moderate drinking to the heart. It is the only reason anyone in academia would be interested in it and yet it is the one finding that went without mention yesterday. 

 
Off the back of a typo in a press release, a study which found that moderate drinking protects against heart disease turned into a story about tiny quantities of alcohol causing heart disease. It’s a good job nobody takes this stuff seriously any more otherwise the public could become confused.

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Disruptive innovation webinar - today

I'll be speaking at a webinar on vaping at 7pm UK time (2pm EST). I'll be mainly talking about how the UK became a success story for tobacco harm reduction by not doing too much. Click here to sign up.

There's a new report to accompany it, including a chapter by me about the British experience.

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The envy of the world

I've got an article in the Daily Mail today about the NHS.

The reality is that it is not normal for a health service in a rich country to have a flu crisis every winter.

We expect to wait months for an operation and are pleasantly surprised if we wait less than several hours in A&E.

We are meant to be impressed by being able to see a GP today, even though we called yesterday. Services that would be substandard in many countries are regarded in Britain as normal, if not excellent.

The fact is that the NHS is a failing system. The UK has 2.5 hospital beds for every 1,000 people, close to half the EU average and less than a third of the number in Germany — or even Bulgaria.

We have 2.8 practising doctors for every thousand people, fewer than any EU country bar Poland and Cyprus and well below the EU average of 3.7 per 1,000.

The UK's cancer survival rates lag behind Italy and France, and more of us die from cancer than do Belgians, the Dutch, Germans, the Japanese and New Zealanders — all countries with a social health insurance system.

Rates of 'avoidable deaths' are even worse.

In 2014, a league table by the Commonwealth Fund found that Britain performed well on 'access', 'equity' and 'care process' but came second-last for 'health care outcomes'.

What does that mean? As the Left-wing Guardian newspaper put it, the 'only serious black mark against the NHS was its poor record on keeping people alive'.

Do have a read.

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The gambling epidemic that never grows

First published by Spectator Health in February 2016

Doctors prescribe drugs to tackle Britain’s gambling epidemic’ was the top story on the Times‘s front page on Wednesday. ‘The growing toll of problem gambling in Britain,’ it said, ‘is now so serious that the NHS has started prescribing £10,000-a-year drugs for some of the worst addicts.’ The Times echoed calls from the Campaign for Fairer Gambling for a ‘crackdown on fixed-odds betting terminals (FOBTs), which have been dubbed the “crack cocaine” of gambling’.

There are several problems with this story. A few years ago, I dug into the claim that FOBTs were the ‘crack cocaine of gambling’ and found that virtually every form of gambling has been given this tag at one time or another. I tracked it back to Donald Trump in the 1980s who used it to describe a video bingo game called Keno which he saw as a threat to his casino business. Since then it has been used to attack video lottery terminals, slot machines, pokies, horse racing, lotteries, casinos, internet gaming and scratchcards.

When my research was published I had the vague hope that people would think twice before parroting the ‘crack cocaine’ claim about FOBTs in the future, but that was clearly in vain. Three years later, it is seemingly impossible for any newspaper to write about these machines without including this evidence-free metaphor.

Secondly, there is precious little evidence that there is a ‘growing toll of problem gambling in Britain’. The British Gambling Prevalence Survey is by far the most thorough body of research in this area. Sadly now disbanded, it produced three reports using two separate methodologies to measure problem gambling between 1999 and 2010. Under one methodology, it found that gambling prevalence was 0.6 per cent in 1999, 0.6 per cent in 2007 and 0.9 per cent in 2010. Under the other methodology, it found prevalence rates of 0.8 per cent in 1999, 0.5 per cent in 2007 and 0.7 per cent in 2010. This suggests little, if any, change in the first decade of this century despite the introduction of FOBTs and the liberalisation of much of the gambling industry.

The British Gambling Prevalence Survey has since been replaced by Health Surveys for England and Scotland. The latest English report, published in 2013, found a problem gambling prevalence of 0.5 per cent under one methodology and 0.4 per cent under the other. The latest Scottish report found a prevalence rate of 0.5 per cent under both measures. If there is an ‘epidemic’ of problem gambling, it has been missed by every reputable survey.

The Times ignores the latest prevalence studies and instead claims that there are 562,000 problem gamblers in Britain. This is based on the fact that ‘the last gambling prevalence survey in 2010 found there were 450,000 problem gamblers in the Britain [sic] but experts at GamCare say the number of addicts is likely to grow in proportion to the size of the industry’.

Leaving aside the dubious assumption behind this factoid, the industry is not growing. After adjusting for inflation, the British gambling sector has a lower Gross Gambling Yield (which essentially means revenue) than it did in 2008. Contrary to popular belief, the number of bookmakers has been falling i the long term and has expanded only fractionally in the short term. The number of bookies peaked in 1968 at 15,782 before falling to an all-time low of 8,732 in 2000. It has risen only very slightly in the years since. At the last count, there were 8,819 bookies in the UK, representing a one per cent rise on the fin de siècle nadir, significantly less than population growth and a far cry from the ‘dramatic proliferation’ claimed by opponents of gambling.

As for the situation getting so bad that the NHS is having to dish out drugs at a cost of £10,000 per person, the prescriptions (for naltrexone) are being handed out by the National Problem Gambling Clinic, a private organisation which is mainly funded by the Responsible Gambling Trust (which, in turn, is entirely funded by the gambling industry). According to the Responsible Gambling Trust, the drug does not cost £10,000 a year. It costs £68 for three months. When I asked them about it, they told me that the clinic has only prescribed it five times since April 2015.

These are not minor discrepancies. There is a world of difference between the publicly funded NHS dishing out £10,000-a-year drugs to the countless victims of Britain’s gambling epidemic and a predominantly privately funded clinic prescribing £272-a-year drugs to five people against a backdrop of problem gambling rates that have barely fluctuated since 1999. But when have facts ever got in the way of a moral panic?

UPDATE

Since this article was written the rate of problem gambling has remained at 0.5-0.7%. It has not fallen since fixed odds betting terminals were effectively banned. See A Safer Bet. The number of bookies has, however, collapsed to 6,735 and thousands of people have lost their jobs.

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