Diabetes and protecting your heart
One of the largest trials we ever funded was the Heart Protection Study, in partnership with the Medical Research Council. It aimed to prove whether reducing ‘bad’ LDL cholesterol levels can cut the risk of heart and circulatory diseases. The study began in 1994, and more than 20,000 volunteers took part, who either were at risk of developing or already had a heart or circulatory disease – including nearly 6,000 people with diabetes.
The study showed taking statins reduced the overall risk of heart attack and stroke by 25%, and significantly reduced the risk of heart attack or stroke in people with diabetes. That is why statins are now often prescribed to people diagnosed with diabetes.
Supported by a BHF grant, Dr Naila Rabbani at the University of Warwick discovered a particular type of LDL cholesterol – more common in people with Type 2 diabetes – that is ‘stickier’ than the rest. MGmin-LDL cholesterol is more susceptible to attaching to the inside of the artery wall, a process that helps to form the fatty plaque that leads to heart attacks and strokes. We’ve known for a long time that people with diabetes are at greater risk of heart disease, and this discovery revealed one possible explanation for that dangerous link.
Why does diabetes stop blood vessels from growing properly?
Diabetes impairs the body’s natural ability to generate new blood vessels. This makes it more difficult to overcome the progression of disease in small blood vessels, and delays wound healing. The combined effects can be devastating, and include heart failure, skin ulcers and gangrene.
BHF Professor Costanza Emanueli and colleagues in Bristol have revealed clues into why diabetes prevents the growth of new blood vessels – a process known as angiogenesis. They’ve discovered a chain of biological steps takes place in mice that have diabetes which disables the cross-talk between blood vessel cells that are essential for angiogenesis.
Importantly, Professor Emanueli’s team found small molecules called microRNAs are critical in this process. MicroRNAs could be prime targets for new medicines to prevent some of the devastating consequences of diabetes.
Ethnicity and diabetes - what’s the link?
Type 2 diabetes is more common in patients of South Asian origin than their white European counterparts, but the reasons aren’t clear. Two major and ongoing urban research studies - called LOLIPOP and SABRE - are shedding light on how ethnic origin can affect the risk of common diseases and conditions, including heart disease and diabetes.
The SABRE study followed-up with 5,000 people living in North London, 25 years after they had participated in previous research. It showed the risk of developing Type 2 diabetes before the age of 80 was roughly double for South Asian and African Caribbean participants, compared with white Europeans. It also revealed that higher levels of amino acid tyrosine – which was measured as part of the study 25 years ago – turned out to be a strong predictor of diabetes in South Asian people, much more so than in Europeans. This was the first study to look at amino acids and diabetes in this context and could pave the way for a brand new approach to measuring diabetes risk.
Searching for the next breakthrough
The link between diabetes and heart disease is well known, yet unexplained. Having diabetes increases the risk of dying from the effects of a heart attack by around 50 per cent..
We urgently need to understand the science behind this association, so we can start work to prevent the dangerous complications of diabetes and save lives.
Find out more about our research into diabetes