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‘The greatest epidemiologist ever – he must have saved hundreds of thousands
from premature death.’ Anyone so called by their peers would be entitled
to bask in the golden glow of retirement, awaiting only the obituarists.
But Richard Doll, who was 80 last month, is not like that at all. He still
puts in a full day’s work and more – unpaid – at the Imperial Cancer Research
Fund unit at the Radcliffe Infirmary in Oxford. As he says, there is still
so much to do to change the disorderly, frequently fatal ways of the world.

As a young man he thought his generation of the 1930s could change the
world, but half a century later he has settled for changing those bits of
it which are susceptible to the force of his intellect. Along the way he
has proved just how powerful epidemiology – the study of epidemic disease
– is as an instrument of modern medical science, saving countless lives
by exposing the lethal link between cigarette smoking and lung cancer. That
doctors can now write ‘smoking’ as a contributory cause on death certificates
is largely due to his indefatigability in the face of both hostility from
the tobacco industry and initial scepticism from other medical researchers.

Despite his battles, he is courteous, quiet, austere – but not without
humour – and many years younger in his face and gait than his age. He is
also sharp, a stickler for the evidence and forthright about contemporary
medical questions. One of his greatest concerns is the debate about the
benefits of lowering cholesterol levels. ‘It’s the most important thing
for the Department of Health to get straight,’ he says. It is not just
the sheer prevalence of heart disease and other atherosclerotic conditions
that makes the cholesterol debate so decisive, says Doll, but the fact that
they are largely preventable. ‘One can do something about them, nationally,
to reduce the risks.’

For almost 30 years medical researchers have been trying to establish
whether lowering cholesterol in blood, either through diet or drugs, reduces
the risk of heart disease. Doll is convinced that it does, but not everyone
agrees.

Late last year Finnish scientists published controversial results purporting
to show that a group of business executives on a controlled diet, low in
saturated fats and cholesterol, were twice as likely to die of coronary
heart disease than those in a control group who followed no particular diet.
This was quickly followed by a paper in the British Medical Journal questioning
the safety of the drugs doctors prescribe to lower cholesterol levels. Five
international studies had found people taking the drugs to be at increased
risk of accidents and violent death. Then, in July, came the much-publicised
claims of a Swedish doctor that the benefits of lowering cholesterol ‘have
been exaggerated by a tendency in trial reports, reviews and other papers
to cite supportive results only’.

None of this sways Doll. The problem is, he says, that a number of people
in Britain misunderstand the statistics and ‘the waters have been muddied
by a number of incompetent reports’. He is convinced that lowering cholesterol
neither increases the risk of colon cancer (as has been claimed) nor makes
people any more likely to die from injuries incurred in accidents. ‘But
with reputable scientists you only need one or two to express contrary results
to confuse the public.’

Most cholesterol is transported in the blood by protein complexes known
as low density lipoproteins, and it is only in this form that the substance
is believed to contribute to the clogging of arteries. Researchers on the
‘anti’ side of the cholesterol debate argue that the more saturated fats
you eat, the more LDL cholesterol you will produce. Some go further and
claim that unsaturated fats are beneficial because they prevent the accumulation
of LDL cholesterol in blood. Doll is ‘quite satisfied’ that the crucial
dietary parameter is the ratio of saturated to unsaturated fat, although,
as he admits, ‘this hasn’t been accepted by all cardiologists’.

With his colleague Richard Peto, Doll is seeking money to launch what
he believes is the only kind of study that can finally resolve the debate:
a large-scale trial, enrolling perhaps tens of thousands of people, designed
to weigh the benefits against the harm, if any, of cholesterol-lowering
drugs. At present such drugs are prescribed only for people at high risk
of heart disease, but Doll and Peto would test their effects on the many
people at lower, but still above average, risk.

Doll talks about opposition to such trials not only from food companies
but from scientists on the other side of the cholesterol debate. ‘It’s extremely
difficult to get money to do this on a big enough scale to get a conclusive
answer. The people with public money are being very tight fisted.’

These are the opinions of a hardened campaigner, someone who is both
adept at the art of persuasion and acutely aware of the forces that sway
public opinion. Doll has ‘given up’ one Sunday newspaper because of what
it has published about the health risks of cholesterol. The perennial problem,
he says, is the tendency of journalists and editors to give equal weight
to ‘people who have studied the subject, are good statisticians and good
biologists’ and the ‘odd views’ of a minority of scientists. ‘You can’t
blame the public for not knowing what to do,’ he says. As one example of
a dissident scientist who has captured the attention of the press, he cites
Peter Duesberg, the California-based virologist who claims that HIV does
not cause AIDS.

Doll likens the public’s confusion over cholesterol today to the attitudes
in the 1950s towards lung cancer and cigarette smoking. He was in the eye
of that storm and had the satisfaction of finally winning hands down. For
some time, though, victory looked uncertain.

Before hearing the story of that famous campaign I asked him about his
early life and his passion for the apparently bloodless study of medical
statistics.

He was born in Hampton, Middlesex, the son of a GP. He was to become
a doctor eventually, but his first love at school was mathematics and he
was always interested more in scientific research than practising medicine:
‘There was so much we didn’t know in those days.’ He decided to read maths
at Trinity College, Cambridge, but was turned down because of a bad concluding
paper in the scholarship exam. ‘The reason I did so badly was because I
had drunk so much strong Trinity ale the night before. I was so annoyed
with myself but I have often thought since that the ale I drank that night
was the best drink I ever had.’

So it was to be medicine, studied at St Thomas’s Hospital in London,
where he wrote an article on medical statistics for the medical school gazette.
He qualified in 1937, when it was already obvious that there was going to
be a war in Europe, and he became part of the tide of youthful social concern
that was disturbed by poverty in England and the rise of Fascism on the
continent. So concerned was Doll about the impact of poverty on health,
his idealism fired by the Spanish Civil War, that he joined the Inter-Hospital
Socialist Society. He was called up to the army in August 1939 and sent
to France in September.

Vivid eye for detail

Nothing happened for seven months then, suddenly, the British were trapped
by the German army and Doll found himself swept along in the terrifying
retreat to Dunkirk, shelled from the ground and strafed from the air. When
he got back to Britain he sat down and wrote his story of the chaos, which
was published 50 years later in the British Medical Journal. It shows a
strong narrative gift and a vivid eye for detail. Throughout the march to
the coast he carried medical supplies in a knapsack, but he kept his morphine
in his hand because of a horror of being hit and being unable to reach for
it.

He was rescued and sent back to England. In 1941 he was posted to the
Middle East where he was in charge of the infectious diseases ward of a
hospital in Egypt and then, for a year, he cruised up and down the Mediterranean
in a hospital ship. Invalided out in 1944 with a tubercular kidney he became
simply one more young doctor looking for a medical research position in
which he could also use his maths. A rare niche. But he found such a job
with Francis Avery Jones studying the aetiology of the peptic ulcer, which
was thought to arise from, among other things, irregular working hours.
As they soon discovered, ulcers are not caused this way, but Doll gained
experience in medical statistics. His next job was with Austin Bradford
Hill, professor of medical statistics at the London School of Hygiene and
Tropical Medicine.

Without knowing it, Doll had discovered his life’s work. But those early
steps were to plunge him into a controversy which echoes even now. With
Bradford Hill he set out to investigate the cause of lung cancer in a project
funded by the Medical Research Council.

The incidence of lung cancer had risen alarmingly during the Second
World War and so had deaths from the disease. Various possibilities were
put forward – atmospheric pollution and the exhaust fumes of cars were favourites,
especially since blinding smog was still common in Britain’s towns and cities.
The MRC wrote to 20 London hospitals asking them to help the Hill-Doll study.
The physicians and ward sisters cooperated so that the team were told whenever
a patient was admitted with possible lung cancer. Cases of gastric and bowel
cancer were in one control group, while patients of the same age and sex
in the same hospitals as those with lung cancer formed another. In all,
the team interviewed some 5000 patients in the two years between 1948 and
1950, of whom 650 proved to have lung cancer.

The study of lifestyle threw up startling and overwhelming evidence.
‘When we analysed the data we were able to conclude that smoking was emphatically
a cause of lung cancer – not just that it was associated with it.’ In reply
to anyone who might question the causal link, Doll is adamant: ‘If by proof
you mean demonstration of a relationship of which the only reasonable interpretation
is cause and effect, and the evidence is strong enough to take action to
try to prevent the disease, I think you can say you’ve got proof.’

Realising the result was dramatic, Bradford Hill and Doll took their
findings to Harold Himsworth, the secretary of the Medical Research Council,
who insisted on another study based on patients in other cities in case
there was something special about London. After the team interviewed patients
in Bristol, Leeds, Newcastle and Cambridge it was clear that the results
were the same and they published their findings in the BMJ. Lung cancer,
they wrote, was almost completely absent in nonsmokers but increased in
line with how much, and for how many years, people smoked.

The reception was indifferent, although similar results were beginning
to emerge in the US. ‘Practically nothing happened,’ says Doll. ‘A lot of
quite senior scientists wrote letters saying it was nonsense – it hadn’t
been shown experimentally and there were all sort of snags – which only
showed that they didn’t understand epidemiology.’

Fear of cancer phobia

So with the help of the British Medical Association, Doll and Bradford
Hill wrote to virtually every doctor in England asking them about smoking
habits. Their intention was to follow the doctors up to see if the smokers
got lung cancer. ‘By 1954 we already had sufficient evidence to predict
who would be likely to get cancer,’ says Doll. After that, most cancer researchers
accepted the link. In 1957 the MRC wrote to the Department of Health saying
that smoking caused cancer of the lung. The Royal College of Physicians
published a report in 1962 accepting it.

‘It was different the nearer you got to the politicians,’ says Doll.
The government kept asking the MRC to do more research but Himsworth refused
on the grounds that it had already been proved. The Department of Health
had an advisory committee on cancer which, in Doll’s words, was ‘very frightened’
about public education. In those days doctors seldom told patients they
had cancer. ‘The advisory committee told the Department of Health that no
public education would be attempted because it would cause cancer phobia,’
says Doll. ‘Their policy was to do nothing and health ministers reflected
this view. Not until the 1960s, the decade after our findings, did society
begin to come to grips with this epidemic disease.’ Before the study Doll
had been a smoker himself.

Although the tobacco industry in this country never attempted to put
pressure on him personally, the fight goes on to this day. Doll says he
would not ban smoking and thus criminalise it, but he would impose stiffer
taxes. ‘Abominable’ is how he describes the industry’s efforts to promote
smoking in the Third World. It was ‘unbelievable’ he says, that Lady Thatcher
should lend her name to Philip Morris – a tobacco company which still claims
that proof that smoking causes cancer has ‘yet to be developed’.

Important though it is, the lung cancer research is only one of many
epidemiological studies undertaken by Doll over the past 40 years. His name
comes very high in a recent survey of the top 50 most frequently cited papers
in the BMJ. As the survey’s author remarks: ‘The emergence of modern epidemiology,
the increasingly detailed study of drug side effects and the considerable
individual influence of Sir Richard Doll are the three themes to emerge
from my study of the top 50.’

Radiation interests

Chief among Doll’s other main interests has been the controversy surrounding
the health effects of radiation. It all started in 1957 when the British
government asked him and a colleague to find out the quantitative relationships
between exposure to radiation and the development of cancer.

Nuclear bomb testing in the Pacific, from which there was fallout all
over the world, had led to enormous public concern. Could low levels of
radiation do enough damage to DNA to pose a health risk? ‘The effects have
now proved to be so small as to be virtually zero, but there was no clear
evidence at the time.’ In 1957 Doll and his colleagues published evidence
that there is a quantitative relationship with leukaemia so they had to
assume that even very small doses had a proportional effect. The worldwide
nuclear test ban treaty stemmed partly from this work.

Another medical advance that interested Doll was the introduction of
oral contraceptives. ‘I saw that it was very important to check that they
had no side effects,’ says Doll. In the mid-1960s, Doll and his colleagues
found that the pill can cause thrombosis depending on how much oestrogen
it contains. Their research was the signal for manufacturers to alter the
make-up of the pill, reducing the oestrogen dose to a safe level. The pressing
question now is whether oral contraceptives cause a slight risk of breast
cancer. ‘I think they do at young ages, but it is compensated for by protection
against cancer of the ovaries.’

At the moment he is working with colleagues at the ICRF and the National
Radiological Protection Board to examine the effects of radiation on servicemen
who took part in nuclear tests in Australia three decades ago. This work
is for the Ministry of Defence and it has about 23 000 participants and
a similar number of controls. Although it is too soon to speculate, early
results show that very few people can have been harmed.

Among his other current interests are the leukaemia clusters around
Sellafield. He has studied the medical histories of the local populations
near 14 nuclear installations and found no evidence of an increase in cancer
generally, with only a small increase in childhood leukaemia. And even with
leukaemia, he emphasises, ‘the clusters do not increase the nearer you
get to the plant’. There is growing evidence that the clusters may instead
reflect factors such as population movement and density. For example, says
Doll, childhood leukaemia tends to be worse in isolated places.

Doll is also involved in the study of the effects of radon in domestic
houses which is being run by the NRPB, Department of the Environment and
the Imperial Cancer Research Fund. The findings, he believes, could lead
to compulsory alterations to more than 100 000 houses in Britain. The gas
collects in fissures in underground rock and people whose houses are built
on rock that is deeply cracked may be exposed to significantly higher levels
of the gas which harms them as they inhale it.

Like the research into smoking, the study is large: by 1994 the researchers
will have interviewed 900 to 1000 patients with lung cancer and four or
five times that number of controls. The radon has to be measured not in
just one house but in every house that the people have ever lived in. ‘The
amount in houses varies enormously – certainly by more than a hundredfold.’
Doll cannot say as yet whether many cases of cancer can be attributed to
radon. Cornwall, parts of Devon and spots in Somerset, Northamptonshire
and Derbyshire are the worst affected.

As chairman of an NRPB committee, Doll is also involved in an inquiry
into the effects of nonionising radiation such as that experienced near
overhead powerlines. ‘It doesn’t look to be a likely cause of cancer but
you cannot put your hand on your heart and say ‘no biological effects’,
so you cannot rule it out yet.’

Was he still the socially concerned scientist that he was when young?
He said that he now looks to a benevolent capitalism to provide for the
needs of the world. He also believes very strongly that whatever might be
laid at the door of industry and science, only industry and science can
solve the problems. The fashionable antiscientism of some of today’s intellectuals
finds no echo here.

Glyn Jones is a science writer and film-maker based in Wiltshire.