Advancing medicine, changing lives - Medical Research Council

PROFILE: Dr Cari Free, London School of Hygiene and Tropical Medicine
Promoting
healthy lives
Diet, education, genetics and lifestyle are
just some of the factors that have an impact
on our health and our risk of developing
diseases like cancer or obesity. MRC
scientists are working to understand more
about how these factors come together
to influence health and disease, making
discoveries that can change the lives of
individuals, communities and
whole populations.
In January 2012 the Department of Health launched
an affordable mobile phone support programme for
smokers, which has been proven to double quit rates. This
programme was developed for UK patients by Dr Cari Free
at the London School of Hygiene and Tropical Medicine
(LSHTM) with MRC funding. Around 1,000 smokers are now
signing up each month.
Cari’s office at the LSHTM is high-ceilinged and airy. The
walls are lined with medical textbooks on everything from
cancer to condoms. It’s here that she works four days a
week as a senior lecturer, leading research studies in public
health. On the fifth day of the week she’s a GP in South
London which keeps her in touch with some of the patients
her research will benefit.
Smoking is a notorious public health problem, causing heart
attacks, stroke and lung cancer and it’s fast becoming an
epidemic in developing countries like India and China. So
affordable and effective ways to help people quit are in
higher demand than ever.
A few years ago, Cari heard about a study in New Zealand
called Stomp, which used motivational mobile phone text
messages to encourage smokers to give up. Results were
promising, but it was unclear whether the text messages
helped people to stop long term. So the LSHTM researchers
decided to do a modified version of the study in the UK to
pin down whether text message support really does help
people to stay off cigarettes. After a successful pilot study,
the MRC agreed to fund a large-scale trial involving 5,800
people, known as Txt2stop.
Five text messages were sent each day to participants for
the first six weeks of the study, preparing them to quit
by asking them to think about why they wanted to stop
smoking. After the quit date they were sent supportive
messages, including reassurances about when the cravings
would subside.
of people who said they’d quit had either relapsed by the
time they saw us or just cut down rather than quit.”
So what is Txt2stop’s secret to success? Was there a
winning formula for the text messages that really cut to the
core of people’s nicotine addiction?
“People said that it was like having somebody at your side
reminding you that you were going to quit and why you
were doing it – and the tone of the messages was definitely
set up to be supportive in that way,” says Cari.
“People particularly liked the messages where they got
feedback about what they’d gained and how well they’d
done. For example we sent messages saying ‘shortly after
you start quitting your carbon monoxide level goes back
to normal’ and then they’d receive a message at the point
when their levels had returned to normal saying ‘well done’.
One person said she was on the way to the shops to buy
cigarettes when she got that message and then turned
around and went home again.”
The research team thinks the text message support works
by helping to sustain people’s motivation at times when
their resolve is weaker, and through providing contact and
support over a 24-hour period. For example, trial members
could text the word CRAVE to receive a supportive message
when they were struggling with craving.
“The peak of a cigarette craving only lasts for a minute,
so part of the idea behind that message was whilst you’re
texting, waiting for the message to arrive and then reading
it, you’re not smoking – and by that point, the craving has
usually subsided,” explains Cari.
Txt2stop was equally effective for all age groups and across
all levels of addiction and its benefits were so immediately
clear that the Department of Health launched the
programme on the NHS smoking website earlier this year.
The results were very exciting, says Cari: “The trial very
clearly demonstrated that text message support doubles
the number of people who quit smoking after six months
compared with those who didn’t receive the texts.”
An important part of the study’s design was independently
measuring whether people really had quit. So study
members also had to post in samples of their saliva six
months after taking part in the trial. These were tested for
cotinine, a by-product of nicotine, which is a stable and
reliable test of whether someone is smoking or has smoked
over the previous few days.
“That was really just to check they were telling the truth,”
explains Cari. “That’s important, because about 30 per cent
“Smoking cessation is one of the most cost-effective
interventions you can make from a public health
perspective because about half of people who smoke
beyond the age of 40 will shorten their life as a result. The
intervention represents a major cost saving to the NHS,”
says Cari.
Txt2stop could have an even bigger impact beyond our
shores. The World Health Organization predicts that by
2030 the annual worldwide smoking death toll will have
risen from six million to eight million, with the biggest
rise occurring in poorer countries. With mobile phone
usage widespread across the world, Txt2stop could offer
a low-cost and effective means of helping people in these
countries to give up.
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