Cholesterol and Statins
Since this is National Cholesterol Education Month, I'd like to chime in on the object of what many of you go to health screenings for: testing your cholesterol. Higher levels of bad cholesterol (low density lipoprotein, or LDL) and lower levels of good cholesterol (high density lipoprotein, or HDL) has been linked to heart attacks, strokes, and other diseases decreasing your lifespan. Recent evidence published by the New England Journal of Medicine (NEJM) suggests that it prevents strokes (CVA) after you've had one, or even just a mini-stroke (TIA, or transient ischemic attack).
One practical tip about testing: remember to fast the morning you go for testing or else your triglycerides will be artificially high. Your triglycerides are one kind of cholesterol in your blood.
The thought is that by reducing your bad cholesterol, you won't have excess cholesterol to absorb into the lining of your arteries that form plaques, or hard spots. These plaques can break the lining open, providing a spot for your blood to clot and block flow to the tissues that need it. If this happens in heart arteries, it causes a heart attack. Your heart is a muscle just like the other muscles in your body and need oxygen from blood to run. Your brain needs nutrients provided by blood, and if a brain artery is similarly blocked, you can have a CVA or a TIA.
Statins are a class of cholesterol lowering drugs which block an enzyme involved in the production of cholesterol. The enzyme is called hydroxy-methylglutaryl-coenzyme A reductase (HMG-CoA reductase) and statins are called HMG-CoA reductase inhibitors because of this. Other possible ways statins may improve health is by decreasing inflammation that is involved in damaging the walls of arteries and forming plaque.
A disclosure before we continue -- I take Lipitor and chalk it up to my genetics, of course not my passion for french fries and foie gras. Lipitor has been in the press a lot recently, as I pointed out earlier, it's the statin studied in the NEJM article. It's the most popular statin, and accounts for a majority of the profits of its manufacturer, Pfizer. It's become this popular because it's more potent than older statins, many of which have lost patent protection and gone generic. It's also been the statin used in many of the more recent studies showing a benefit to our heart health.
One controversy I've been interested in is the catfight between those who believe in using the drugs listed in these research studies, and those who believe that the heart-protecting qualities of one statin apply to all of the medications in that class. Kaiser, a health maintenance organization or HMO, is a strong proponent of taking higher doses of generic statins to achieve the choleterol lowering that it takes to protect your heart. Some of my favorite bloggers have chimed in against the recent NEJM study, showing the increased company profits from the study, considering one statin equal to another, and troubled that the study focused on a dose of lipitor rather than a level of cholesterol lowering.
Whether you believe in one statin over another - one thing's clear. Lowering your cholesterol by improving your diet and increasing your exercise can help. For some, that's not enough, and a statin can help, like with me! If you're over the age of 25, ask your doctor to test you as part of your health care maintenance, and possibly even if you're younger if you have a family history or risk factors.
95 Commenting on statin & lipitor & stroke at technorati.
Update: Huge thanks to my favorite diabetes blogger Amy Tendrich of Diabetes Mine for presenting this post first in Grand Rounds Volume 2 Number 51. I hope I can be as creative and thoughtful when I host Grand Rounds in 2 weeks. One clarification to readers is that Kaiser uses generic statins at a higher dose to achieve the same lowering of cholesterol that a more potent statin at a lower dose achieves, such as Lipitor. Kaiser believes they can save on costs by using generics and achieve the same health outcome. Companies producing branded statins such as Lipitor are trying to say that cholesterol lowering isn't the only way they help, and that you have to use THEIR drug to get the other effects. That's the purpose of the NEJM study I mention at the beginning of this post.