Myths about lipid-lowering treatment
It is a well-established fact that hyperlipidaemia is a threat to coronary arteries and it is also the most important risk factor for coronary heart disease. And, with several guidelines in place, there still exist some myths surrounding the approach to lipid-lowering therapy.
Myth 1 – If blood cholesterol level is normal no lipid lowering is required!
Fact- There is no such thing as normal cholesterol value, rather blood cholesterol levels are a continuum and benefit of lipid lowering depends on level of bad cholesterol (LDL-Cholesterol) and the associated risk factors manifest coronary artery disease (CAD).
- If LDL-C is >180 mg% there is benefit of lipid lowering even if no other risk factor is present
- If some risk factors of CAD are present (but no manifest CAD) the levels of LDL-C should be targeted to <130mg%
- If manifest CAD is present, the LDL-C value should be kept ≤70 mg%
- If fulminant CAD is present e.g. recurrent MI or appearance of new lesions, LDL-C value <40 mg% is advisable.
Myth 2 – As long as blood cholesterol levels are controlled, you can choose any lipid lowering agent!
Fact- All lipid lowering agents are not equal. Probucol when used as a lipid lowering agent has been shown to increase non-cardiovascular mortality. Niacin has not been found useful either in reducing events or reducing mortality. Fibrates reduce event rates especially in diabetic patients but are not known to reduce mortality.
It is only STATINS (Rosuvastatin, Atorvastatin, Simvastatin, Pravastatin) which are unequivocally known to reduce not only CV events but also mortality. The benefits of statins manifest not only in patients with known CAD but also in those without CAD but with presence of risk factors. Newer lipid lowering agents like ezetimibe and PCSK9 inhibitors could be useful in patients where optimally-dosed statins alone are not enough. In this case these drugs can be combined with statins.
Myth 3 – Low blood cholesterol levels can cause harm!
Fact- As yet no lower value of LDL-C has been found to induce any harm. At the time of birth, LDL-C value is ~20 mg% and therefore even a value as low as this may not be associated with any harm. Low levels of blood cholesterol are required for essential metabolism by the body. Thus, even a value of LDL-C 30-40 mg% can be considered safe.
Myth 4 – One can stop lipid lowering medication after blood cholesterol levels are achieved!
Fact- In dyslipidaemic patients blood cholesterol levels are achieved as a result of lipid lowering strategy. If one discontinues lipid lowering efforts blood cholesterol levels will rise again. Thus it is essential to continue lipid lowering steps even after blood cholesterol levels are controlled.
Myth 5 – In people with elevated blood cholesterol, all dietary cholesterol should be prohibited!
Fact- A significant amount of blood cholesterol is synthesised in the liver from the total fat load consumed in the diet. Some amount of blood cholesterol can also come from dietary cholesterol especially if consumption of dietary cholesterol is high. Blood cholesterol level depends on synthesis and utilisation. Thus dietary cholesterol is harmful only if it is consumed in excessive amounts. Thus, in current guidelines even 2 eggs/day (including egg yolk) are permissible if no other source of dietary cholesterol is partaken. In diabetics this limit is 1 egg/day.
