Confirmed: Lowering LDL is Effective

There’s a hidden story behind the groundbreaking Zetia/Vytorin Study. Just as important as the confirmation of the effectiveness of the new drug ezetimibe is the more general result that lowering your LDL (bad cholesterol) is good for you.

Huh? Didn’t we already know that?

You may be as surprised as I to learn that the medical guidelines for prevention of heart disease and stroke do not say you should lower your LDL – they say you should take statins. It’s a rather subtle but very important difference. Statins lower your cholesterol but also have anti-inflammatory effects which cannot be readily separated in a typical study. This new study showed the addition of the second LDL-lowering drug (combined as Vytorin) worked better than the statin alone, giving direct evidence for the reduction of heart attack and stroke risk. This drug decreases the uptake of LDL in the gut so other approaches that reduce LDL intake or absorption are likely to be beneficial as well.

I first learned of these narrow guidelines from my doctor in her response to my own approach to lowering LDL. In addition to my low-dose of statin I added a collection of other supplements that are known to reduce LDL (plant sterols/stanols, fiber, garlic). When I conveyed this to her, she said those are fine but if you forget to take any pills (she knows me well) don’t forget to take the statin. “Why is that?”, I asked. “Because I have no medical evidence that lowering LDL alone is going to protect you from a stroke”, she said. Before yesterday, that was true.

So although this study will have a huge impact on Vytorin sales (thankfully off patent in 2016), the far more important result will be new medical guidelines for lowering LDL opening the way for the prescription of other preventative treatments, including drugs, supplements, and diet.


Double whammy: two hidden stroke factors, one congenital and one inherited

From an article on a Fitness Instructor’s stroke

Fortunately for Jessica, she woke up the next day with feeling in her left leg and few other symptoms than a little grogginess and fatigue. While she had no previously known medical issues, doctors discovered what they believed caused Jessica’s stroke as a PFO, or patent foramen ovale, a small hole in heart that had been undetected all her life and a blood condition called Factor 5 Ledion [Leiden], making her more prone to clotting. Jessica’s team of physicians, have recommended she undergo surgery to close the hole in heart, which she will proceed with this spring and she is taking an asprin a day to regulate blood clotting.

The frequency of the congenital heart defect patent forman oval (PFO) is between 20-30% based on post-mortem studies of normal hearts. The most common Factor V Leiden mutation related to thrombosis has an occurrence of 4.4%1 in Europeans and Caucasions (one of the most common monogenic disorders in the Caucasian population).

Combining those gives a range of 0.8% and 1.3% for having the condition and the mutation.    This is surely an oversimplification of the probability, but this seems remarkably high, and could combine with other factors to increase the risk of blood clots.    Since her doctor recommending heart surgery, she may have two copies of the Factor V disease variant or other unmentioned factors.

Earlier PFO estimates were 10-15%. Recent higher estimates draw suspicion about this as a causative factor for embolisms. Here’s a counterpoint on the “indictment of the PFO as a source of embolic stroke”.

  1. Prevalence of the factor V-Leiden mutation in four distinct American ethnic populations.