Coronary heart disease (CHD) is the single biggest cause of health problems and death in the USA and the world.
Statins offer a way to help treat CHD, but have become perhaps too heavily pushed. And the target level of cholesterol to reach may have been lowered too far.
What causes CHD?
CHD is most often caused by the build up of plaques on arteries and other blood carrying vessels. The plaque is made of various components, but deposits of cholesterol tend to play a key role. When it becomes too thick, it can stop blood flow, causing a heart attack or other damage.
The plaque can also break off and float around the body. If that happens, it can harmlessly dissolve. Or it can clog a blood vessel pretty much anywhere, potentially causing a stroke, heart attack, or thrombosis.
The late 1980s heralded the discovery of a class of drugs called the statins.
These medications, technically termed 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, lower levels of cholesterol. Because of the role cholesterol plays in plaque formation, the statins were found to dramatically decrease risk of serious heart damage.
Statins were so effective that a lot of influential doctors argued that the lower cholesterol levels were, the better. LDL, or low density lipoprotein, was specifically targeted. And in the early 2000s, aggressive new targets for treatment were released. LDL levels should be lowered below 100 mg/dL.
But a lot of the proponents of the new, lower levels were found to be on the pay for major drug companies. And it’s not entirely clear if aggressive lowering of LDL levels provides the most benefit.
LDL must be lowered?
It’s most likely that lowering of LDL follows a logarithmic pattern. In at risk patients, a small reduction provides a major reduction in risk of having a heart attack. As levels are lowered even further, however, the benefit becomes increasingly smaller.
A few major studies support the idea that LDL levels shouldn’t be over aggressively lowered. The HARP study showed that lowering levels below 100 mg/dL showed no increased benefit.
The WOSCOPS study gave similar results, as well as AFCAPS. Additionally, several major studies into the non-statin drug Ezetimibe showed that its reduction of LDL did not mean better clinical results for patients.
Potential side effects:
There may be a downside to over aggressive treatment. Low levels of LDL may theoretically contribute to hemorrhagic stroke. Statin therapy does have side effects including myopathy and we know especially little about the effects of the high doses needed to achieve the lowest levels of LDL.
Some data show a slight increase in certain types of cancer for statin use, although such an effect may be statistically insignificant.
There is no doubt that statins have played a major role in reducing heart disease across America. But it is also not entirely clear who should be given them, and how heavily they should be used.
With the guidelines for cholesterol treatment being written substationally by doctors on the payroll of major drug companies, skepticism is called for.
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