New research has found that metformin – a cheap drug routinely
used for the treatment of type 2 diabetes – could help millions
of people living with heart and circulatory disease in the UK.
Two studies involving the drug, led by researchers at the
University of Dundee and presented today at the British
Cardiovascular Society (BCS) Conference in Manchester, have
provided promising results for patients with high blood
pressure-induced heart damage and a condition called aortic
stenosis, which causes heart failure.
The MET-REMODEL trial, which was funded by the British Heart
Foundation, found that metformin could reverse harmful thickening
of the left ventricle - the heart's main pumping chamber. It also
helped to bring down high blood pressure and reduce bodyweight in
patients who had a heart attack.
The study involved treating people with coronary heart disease
with metformin or placebo over a period of 12 months to see how
the drug affected the heart and circulatory system. The dangerous
thickening of the left ventricle was reduced by twice as much in
those taking metformin compared to the placebo. Patients who took
metformin also had reduced blood pressure and lost an average of
3kg, compared to no weight loss in the placebo group.
Thickening of the heart’s main pumping chamber, or left
ventricular hypertrophy (LVH), is a serious risk factor for heart
attack and heart failure. It is often silent and so most people
don’t know they have it until they have a heart attack or stroke.
Major causes of LVH are high blood pressure, inflammation and
insulin resistance, which are also thought to be key drivers of
coronary heart disease.
In another study, funded by Scotland’s Chief Scientist Office
(CSO), the researchers looked at the records of diabetic patients
with a condition called aortic stenosis (AS). In people with AS,
the main artery which supplies blood to the body is narrowed. It
affects around 40% people over the age of 60 in the UK and can
lead to LVH and subsequently heart failure. The team found that
diabetic patients with AS who were treated with metformin were
less likely to die from heart attack, stroke or heart failure
than those on other diabetes treatment.
Using a variety of research approaches, including big data and
genomics, the researchers have identified some of the mechanisms
through which metformin might be exerting its beneficial effects.
They now believe the drug is helping AS and LVH patients by
tackling insulin resistance and inflammation, which then leads to
a reduction in the size of the left ventricle.
Dr Ify Mordi, a Clinical Lecturer in Cardiology at the University
of Dundee, who co-led the research1 and is presenting the results
as a finalist in the Young Investigator Prize competition today,
said:
“Metformin is emerging as a serious prospect for the treatment of
some forms of heart and circulatory disease. We know from our
previous research that it can reduce inflammation, which is
understood to be a major player in the development of heart
disease. This new research shows that metformin could potentially
become a new treatment option for patients with aortic stenosis
and thickening of the left ventricle. We need to undertake bigger
studies to confirm our findings, but if successful this could
offer hope for thousands, if not millions of patients across the
UK.”
Repurposing of cheap and readily available drugs for use in other
diseases is an important route to explore. On average it costs £2
billion and can take up to 12 years to develop a new drug from
discovery to approval for use in people. The success rate is low
(<5%), and new drugs come at a significant cost to the health
service. Because of this, repurposing of drugs for the treatment
of heart and circulatory disease could potentially save the NHS
billions of pounds every year.
Professor Jeremy Pearson, Associate Medical Director at the
British Heart Foundation, which part-funded the research, said:
“These studies provide real hope that metformin might help to
reduce deaths from heart and circulatory diseases, which
currently claim thousands of lives every year. Repurposing of
drugs like metformin is a great example of how scientists can
harness the power of medications which have more than one target
in the body.”
