It is important to realise that doctors have to be very careful when discussing cholesterol as a risk factor for heart disease. Many large corporations are heavily invested in promoting cholesterol as a cause of heart disease so they can sell you a product to lower it therefore I choose my words carefully.
My Opinion
First off I look at the ratios of cholesterol in terms of a ratio between good (HDL) and bad (Non-HDL) cholesterol*. Although a more reliable test is Apolipoprotein B / Apolipoprotein A but we don’t do this test in the UK. This tells me the level of “dyslipidaemia” – a term used to describe how unhealthy the levels of fats in your bloodstream is. This gives me an indication of “insulin resistance” and something I can put in context of other findings from the examination. Whilst poor cholesterol ratios can indicate risk, my opinion is that it does not cause heart disease and this means that lowering cholesterol using drugs is making the numbers look nicer but isn’t really treating the problem. The caveat, is that “statin” medications are anti-inflammatory which is why they have some effect on reducing risk of cardiovascular disease, whilst other drugs that also lower cholesterol don’t seem to have any effect.
In summary, abnormal cholesterol ratios are likely to indicate insulin resistance especially if your waist to height ratio is more than 0.5. It is incumbent on me to recommend you discuss this with your doctor thoroughly as I can’t advise on individual cases.
Cholesterol history
Cholesterol is a controversial risk factor for heart disease, the history of which stems from several places in particular. In looking at these four places it becomes harder to believe there is good science to the hypothesis that cholesterol is causal of cardiovascular disease.
- The diet heart hypothesis which originated with a researcher called Ancel Keys who on the basis of his seven countries study identified a correlation between high saturated fat consumption and heart disease. Significantly he had data for 22 countries but felt it was only necessary to include data that fitted with his hypothesis.
- Rudolph Virchow who was a pathologist in the late 1800s discovered cholesterol inside arteries which were narrowed. Subsequent to this Nikolaj Nikolajewitsch Anitschkow fed rabbits cholesterol and determined that it led to accumulation of cholesterol in the arteries. This cruel experiment proves nothing except rabbits don’t particularly thrive on being force fed food they can’t process properly but it was enough to convince some people.
- Hypercholestrolaemia, a condition of abnormally high levels of cholesterol in which sufferers have accelerated development of heart disease. It is a rare condition and therefore the studies on the underlying pathophysiology are still being debated.
- In addition there is also the question of “trans-fats” which come from processed vegetable oils which are now banned in several countries due to causing health problems. These oils were introduced in the 1920s and speculated to have played a role in increasingly cardiovascular disease rates at the time of the initial cholesterol studies.
Cardiovascular risk and QRISK
In order to assess your risk we combine information like blood pressure, body mass index, age, gender and whether you suffer from certain conditions to give an estimate of risk of cardiovascular problems (heart attacks and stroke) over the next 10 years. This is based on a population study called Framingham and this is called a QRISK calculation. QRISK can be high even with normal cholesterol. Cholesterol in many ways is increasingly considered to be a controversial risk factor for heart disease (see below).
Statin drugs
Statin drugs were initially designed to lower cholesterol. However, there is now controversy about how statins actually work. There is evidence they reduce inflammation of blood vessels and reduce clotting. Although cholesterol is lowered by taking statins, this may not be a therapeutic effect as other cholesterol lowering drugs have not been shown to reduce risk of cardiovascular events.
Controversies in Cholesterol and Statins in “Primary prevention”
There is seemingly little connection between levels of cholesterol and levels of heart disease in most countries. Notably the Swiss and French have very high levels of cholesterol and yet the lowest levels of heart disease in Europe. Russia which has low levels of cholesterol has some of the highest rates of heart disease. Moderate to high levels of cholesterol may be healthier in women who seem to benefit from this according to a major Norwegian study .
Although risk of heart attack and stroke is confirmed to be reduced significantly in some studies (not all) improvements in life expectancy have not been demonstrated for those without pre-existing heart disease clearly stated in this letter from Pfizer to Dr Eddie Vos.
Concerns over industry bias have arisen as the only major non-pharmaceutical company study conducted (ALLHAT –LLT) shows no benefit in statins in a range of patients.
Side effect from drugs may be under estimated as a result of large industry funded studies and independent studies have shown as much as 40% increased fatigue, 48% increase in diabetes risk and possibly depression and memory issues.
Profitability is another controversy as statins have made pharmaceutical companies billions, estimates suggest that Pfizer had earned over $100 billion from Atorvastatin. Furthermore 8 out of the 12 members of the advisory committee for NICE on statins were reported to have direct financial ties to pharmaceutical companies which manufacture statins.
There is little robust evidence that statins help women at all in primary prevention.
How can I reduce my risk without taking drugs?
Stopping smoking, exercising regularly and reducing sugar and adopting a “Mediterranean” diet◊have been shown to reduce risk. There are studies showing reduced levels of stress may reduce cardiac risk and certainly an abundance of evidence to show depression can increase your risk.
Diet, cholesterol and heart disease controversy
Many institutions still recommend a low fat diet, despite clear research showing no clear evidence of a link between fat and heart disease. In fact cardiovascular disease is strongly associated with type 2 diabetes which is caused by too much carbohydrate in the diet in particular refined sugars and fructose. Although type 2 diabetics are overweight, this is a result of insulin causing the liver to store fat. Sometimes this is referred to as metabolic syndrome where there is type 2 diabetes, high blood pressure and high levels of “bad” cholesterol. Reducing the carbohydrate intake may slow this process or cause it to improve. I recommend diabetes.co.uk for more information.
*Good cholesterol and bad cholesterol in fact relates to the way the cholesterol is packaged in something called a lipoprotein which allows it to move in the blood. Cholesterol itself is vital to our bodies and is used by all cells and we would die without it.
◊The principal aspects of this diet include proportionally high consumption of olive oil, legumes, unrefined cereals, fruits, and vegetables, moderate to high consumption of fish, moderate consumption of dairy products (mostly as cheese and yogurt), moderate wine consumption, and low consumption of non-fish meat products.
References
Effects of Statins on Energy and Fatigue With Exertion: Results From a Randomized Controlled Trial. Beatrice A. Golomb, MD, PhD, Marcella A. Evans, BS, Joel E. Dimsdale, MD, and Halbert L. White, PhD
Statin use and risk of diabetes mellitus in postmenopausal women in the Women’s Health Initiative. Culver AL, Ockene IS, Balasubramanian R, Olendzki BC, Sepavich DM, Wactawski-Wende J, Manson JE, Qiao Y, Liu S, Merriam PA, Rahilly-Tierny C, Thomas F, Berger JS, Ockene JK, Curb JD, Ma Y.
Psychiatric adverse reactions with statins, fibrates and ezetimibe: implications for the use of lipid-lowering agents. Tatley M, Savage R.
Message to NICE: statins fail to save women. Eddie Vos
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