What is cholesterol?
Cholesterol is an essential fatty substance, used by every cell in our body. But if you have too much of it in your blood - and it’s combined with certain proteins – it can cause deposit in the walls of blood vessels, causing atherosclerosis to develop. This is where the blood vessels become narrowed and furred increasing the risk of having a heart attack or stroke.
Read more about cholesterol.
Over the years, we’ve funded studies that have shaped the way we treat high cholesterol, preventing many premature deaths from cardiovascular disease in the UK and beyond.
The cholesterol-lowering drugs known as statins became available in the late 1980s, and were initially known for secondary prevention: to stop heart attack survivors from having another heart attack.
In 1989, BHF Professor Stuart Cobbe and colleagues launched the first clinical trial to see if statins could prevent heart disease in the first place – known as primary prevention. The West of Scotland Coronary Prevention Study (WOSCOPS) showed statins had impressive benefits. They safely lowered cholesterol and reduced the risk of a first-time heart attack by nearly a third.
The volunteers who took part in WOSCOPS began with high cholesterol and the next step was to ask whether lowering cholesterol more widely in other groups of people was safe and beneficial.
So, the Heart Protection Study launched in 1994. It was jointly funded by the BHF and the Medical Research Council (MRC), and turned out to be a clinical trial that would shape modern medical practice.
The 20,000 participants recruited were considered to be ‘high-risk’ of death due to heart disease. These included people who already had signs of coronary heart disease – such as angina – or who had other risk factors such as diabetes or high blood pressure. Half the participants took a daily statin, while the other half took a dummy ‘placebo’ pill, and everybody’s health was tracked over five years.
What did we learn from the trials?
The researchers, led by BHF Professor Rory Collins, found that cholesterol-lowering with statin treatment reduced the risk of heart attacks and strokes by at least one third, as well as reducing the need for arterial surgery, angioplasty and amputations. Reductions in these events were also found in a wide range of ‘high-risk’ patients who had not been investigated in earlier trials. The beneficial effects of treatment also increased throughout the 5 years of the study, suggesting that long-term improvements can be had by continuing to take statins. Overall, those taking statins were about 25 percent less likely to have a heart attack or stroke, or to die from heart disease.
Since then, statins have played an important role as UK deaths from coronary heart disease have declined.. The results of these BHF-funded studies, together with others, means statins are now prescribed to millions of people to reduce their risk of developing heart and circulatory disease.
A new risk factor
Until recently, we mainly talked about ‘good’ HDL cholesterol, and ‘bad’ LDL cholesterol. The difference between them is the carrier molecule – called a lipoprotein – that cholesterol is attached to, which determines how it behaves in our bodies. Today, we think of ‘bad’ cholesterol as being all non-HDL cholesterol, not just LDL cholesterol.
Research led by BHF Professors John Danesh, Hugh Watkins, Rory Collins and Nilesh Samani was crucial in making this advance. Their work identified multiple new risk factors, including one molecule called Lipoprotein A, or Lp(a)
Several major studies form this group of researchers strengthened the evidence that Lp(a) has a causal link to coronary heart disease. This means that people with higher levels of Lp(a) are at higher risk of having heart disease.
Thanks in part to this research, doctors now take notice of all non-HDL cholesterols in our blood when considering how to reduce our risk of cardiovascular disease.
Can you inherit high cholesterol?
Familial Hypercholesterolaemia (FH) is an inherited condition affecting around one in 250 people. It causes very high levels of harmful LDL cholesterol. We’ve been a major funder of FH research, particularly through our support for the leading UK expert in FH, BHF Professor Steve Humphries.
Without diagnosis and cholesterol-lowering treatment, about 50% of men and 30% of women with FH will develop coronary heart disease by the time they’re 55. But, until then, the disease can go completely unnoticed – a silent timebomb.
FH is caused by faults in certain genes. With funding from the BHF, Steve Humphries developed a DNA test and showed that we could find other affected family members before it’s too late, by screening the relatives of a person known to have FH.
Today, thanks to research funded by the BHF over three decades, national UK guidelines for doctors say that first-, second- and third-degree relatives of a patient with FH should be contacted and offered a DNA test. It’s known as cascade screening, and it’s saving lives across the country.
Working to remove the risk
The advent of statins has had a huge impact on coronary heart disease prevention, but still the UK loses 180 mothers, fathers, sons and daughters to heart attack every day.
Harmful cholesterol is a major risk factor for cardiovascular disease, but statins aren’t right for everyone. We’re funding research to find alternative ways to lower cholesterol as well as to curb the damaging effects of cholesterol on our arteries.