Café with Heart, 8th November 2017: Cholesterol: the good, the bad and the confusing
Café with Heart returned this month with “Cholesterol: the good, the bad and the confusing” presented by Prof Chris Packard.
Prof Chris Packard is an Honorary Professor of Vascular Biochemistry at the University of Glasgow and a Consultant Clinical Scientist for NHS Greater Glasgow & Clyde Biochemistry. Prof Packard has dedicated his career to atherosclerosis research, investigating lipoprotein metabolism and how they are affected by diets and drugs, and large-scale clinical trials of lipid lowering agents.
Chris captivated his audience at Waterstones, Byres Road describing cholesterol, the epidemiology of atherosclerosis and dilemmas that face clinicians when treating a large population of people who can be at risk of developing atherosclerosis and co-morbidities This led to a lively and enjoyable discussion with the public where they had the chance to get answers to burning questions such as “What does cholesterol actually do?” and “Are there any ethnic groups more prone to high cholesterol?”.
Chris explained that cholesterol is an important “molecule of life” that can be ingested with our diet or produced internally by each cell. In mammals, including humans, cholesterol plays an important role in maintaining cell membrane stability and is a precursor for several hormones, including testosterone and oestrogen. However, as human population moved from hunter-gatherers to farmers and now to a modern style of life in big cities, cholesterol levels in our bloodstream have risen, transforming this molecule from friend to foe. When transported in our bloodstream, cholesterol can be associated with different proteins that will determine its fate – whether it will be taken to the liver and excreted (high-density lipoprotein – HDL) or delivered to other tissues/deposited in blood vessels (low-density lipoprotein – LDL). In the recent years, clinicians reviewed their opinions on HDL, commonly known as “good-cholesterol”, as clinical trials show that high HDL levels are not protective and the development of cardiovascular disease, such as atherosclerosis, is mainly dependent on LDL (“bad cholesterol”) levels.
Chris described how LDL-cholesterol levels lead to accumulation of cholesterol at the arterial wall and pathological changes in vascular wall layers, including endothelial cells dysfunction, changes in smooth muscle cell phenotype, inflammation, and recruitment of immune cells, promoting formation and growth of an atherosclerotic plaque. Stable plaques can gradually obstruct vascular lumen and decrease the supply to organs and tissues. Unstable plaques not only obstruct the blood flow but may rupture, leading to more serious complications such as heart attack or stroke.
Prof Chris Packard describing cholesterol research to his audience at Café with Heart in Waterstones Café, Byres Road
The public discussed statins which are the most common drug class used to lower LDL-cholesterol levels. These can lower the risk of cardiovascular complication by 60% after only a year of therapy. Long-term treatment with statins, which can now be bought across the counter, has few side effects, making them a prime choice for treatment and prevention of atherosclerosis. New emerging therapies were discussed such as PCSK9 inhibitors which increase LDL-cholesterol uptake by the liver, drastically lowering the LDL-cholesterol levels in the bloodstream and decreasing the risk of cardiovascular disease development and progression. Due to its high cost it is only prescribed to people with familial hypercholesterolemia, who due to a genetic mutation have high levels of LDL and can develop CVD by the age of 30-40 years.
The dilemma remains and was discussed: should we proceed with lifestyle change (eat healthy, exercise, quit smoking and abstain from excessive alcohol consumption); or should we prescribe statins as a preventive therapy and target people in their 40-50s, before they develop atherosclerotic plaques in their vessels.
Café with Heart will return in 2018.
First published: 20 December 2017