Monday, November 18, 2013

NEW GUIDELINES FOR LDL-C. NO MORE SPECIFIC LDL-C TARGETS.

It has been quite a few years since the release of the ATP 3 about 10 years ago. Well, the American College pf Cardiology, the American Heart Association and the NHLBI have released their new recommendations. I have not understood why they did not call it the ATP 4 as these are experts who were also involved with ATP 3. Their paper is entitled,

  1. Stone NJ, Robinson J, Lichtenstein AH, et al. 2013 ACC/AHA guideline on the treatment of blood cholesterol to reduce atherosclerotic cardiovascular risk in adults: A report of the American College of Cardiology/American Heart Association. J Am Coll Cardiol 2013. 
Well these recommendations have essentially done away with specific targets, but emphasize that physicians should pay greater attention in reducing cholesterol in 4 groups of patients whose risk for a cardiac event is >7.5% in 10 years.

The Four Major Statin Groups
The four major primary- and secondary-prevention patient groups who should be treated with statins were identified on the basis of randomized, controlled clinical trials showing that the benefit of treatment outweighed the risk of adverse events. The four treatment groups include:
  • Individuals with clinical atherosclerotic cardiovascular disease.
  • Individuals with LDL-cholesterol levels >190 mg/dL, such as those with familial hypercholesterolemia.
  • Individuals with diabetes aged 40 to 75 years old with LDL-cholesterol levels between 70 and 189 mg/dL and without evidence of atherosclerotic cardiovascular disease.
  • Individuals without evidence of cardiovascular disease or diabetes but who have LDL-cholesterol levels between 70 and 189 mg/dL and a 10-year risk of atherosclerotic cardiovascular disease>7.5%.
    For these for groups at increase risk of CV events, they should be started on statins should their LDL-C be elevated. Meaning that the benefits of statins outweigh the risk of statins. 
    This makes better sense to me.

2 comments:

bao said...

Some are critical of this new AHA's guidelines:-

It is hard for me to believe that this is where modern medicine is at. I guess nobody needs to see a health care professional anymore—just put your numbers in and if you have a 10-year heart attack risk of >7.5%,then you must take a statin for the rest of your life. I have one word for this nonsense: fugetaboutit. The new guidelines are contained in an 85 page, mind-numbing document. It is a very difficult manuscript to read. I will take pieces of it and share my concerns with you. Let’s start with the recommendations that would put most adult Americans on statin drugs. On page 18, the report states, “Data has shown that statins used for primary prevention have substantial ASCVD (atherosclerotic cardiovascular disease) risk reduction benefits across the range of LDL–C levels of 70-189 mg/dL.” Of course, that is after the “experts” state that it is unclear of lowering LDL-cholesterol levels have any benefit. Nonetheless, the authors cite a meta-analysis by the Cholesterol Treatment Trialists’ (CTT) to support their conclusion. (1) The CTT article was a meta-analysis of 27 randomized trials to ascertain whether reducing LDL-cholesterol levels with statin use reduces vascular events in people who are at a low risk for cardiac events. The authors of the article reported that reduction in LDL-cholesterol levels with a statin reduced the risk of major vascular events by 21%. However, this is a relative risk reduction. When deciding whether to prescribe a statin for a patient, the 21% relative risk reduction should not be used. Unfortunately, most (or nearly all) doctors have absolutely no understanding about statistics and what relative risk means. What has more clinical meaning is the absolute risk reduction. “Absolute differences in risk are more clinically important than relative risk reductions in risk and deciding whether to recommend drug therapy.” (2) I and my trusty calculator went to work to figure out the relevant numbers. The absolute risk reduction in the CTT study was 0.77%. The authors should have reported, “The reduction in LDL-cholesterol levels with a statin reduced the risk of major vascular events by 0.77%.” According to the CTT numbers, 129 people would need to be treated with a statin for at least five years to prevent one vascular event. That means that 128 subjects took the statin without any benefit and they could have developed adverse effects. In other words, this study showed that statins failed 99.3% of those (128/129) who took them. So, tell me, does this study make you want to take a statin to prevent a vascular event? If anything, it should make you think the opposite.
Source:-
http://blog.drbrownstein.com/453/

Also,
Majority of panelists on controversial new cholesterol guideline have current or recent ties to drug manufacturers
http://www.bmj.com/content/347/bmj.f6989

hmatter said...

Hi Bao, you are right about this relative / verses absolute risk reduction bit. I believe that the relative risk reduction startegy was invented to make the numbers look better. In the issue of Primary Prevention, the role of statins is more controversial.
However, in the issue of secondary prevention, the role of statins are much clearer. The adsolute risk reduction is much more and obvious.
Looks like this issue of LDL-C and atherosclerosis is not so straight forward. Then there is also the complex issue of inflammation.