Cholesterol Management 2013 and Beyond: Two Roads Diverged

November 18, 2013

New ACC/AHA guidelines abolish specific lipid targets, reclassify populations at risk, and recommend statins for their pleiotropic effects.

The week of November 11, 2013, saw release of the long-awaited update to what had become a stale approach to cholesterol management in the long-term war against cardiovascular disease. Is the document a radical departure from what had gone before (the last was released in 2003 with an addendum in 2004)?

The answer is a resounding “yes.” Since this 2013 version can be characterized as a “paradigm shift,” let’s count some of the ways.

Instead of a cacophony of people at variable risk and a cornucopia of medications expected to mitigate that risk (simply by lowering LDL)-relying on the wisdom of William of Ockham-the committee declared simple is better. The American College of Cardiology/American Heart Association Guidelines on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults now focuses on 4 at-risk groups:  

1. The so-called secondary prevention cohort consisting of individuals who have already experienced a cardiovascular event;
2. The population with LDL cholesterol levels of 190 mg/dL and greater;
3. Individuals with type 2 diabetes mellitus aged 40 to 75 years without a history of a prior cardiovascular event and a LDL cholesterol level between 70 and 189 mg/dL; and
4. Individuals with a 10-year or greater risk of a cardiovascular event as calculated by an equation provided in the document.
 
Another feature oozing simplification is removal of onerous treat-to-target LDL values. How many times have health care professionals adjusted statins to achieve that “magic” LDL of 70 mg/dL or below? Not anymore! Specific situations are outlined for the use of moderate-intensity and high-intensity statin doses. The layers of targets have evaporated. Remember, the good that flows from statins does not come solely from lower LDL levels per se. Benefits are also accrued from a range of statin-mediated pleiotropic effects  that augment the benefits of lower LDL levels.
 
The committee looked to a gold standard-Evidence-based Medicine. If the literature could not justify a practice (eg, the absolutely perfect secondary prevention LDL level of 70 mg/dL or robust data to support certain non-statin drug benefits in lowering cardiovascular risk) it was not included in the recommendations.

At the risk of being a Monday morning quarterback, there were issues, at least for me, either conspicuous by their absence or less well developed than I would have liked. I have struggled with my ability to assess cardiovascular risk as a primary prevention strategy. Sometimes I use Framingham and sometimes the Reynolds risk score. I wrote earlier that the money seems to be in the considerable heterogeneity found in the intermediate risk cohort. Some of these folks are intermediate, but some are at considerably higher risk. Do other tests-C-reactive protein, CT coronary calcium scores, ankle-brachial index, and in CKD, FGF-23-allow for finer discrimination of that risk? If the answer is yes, the current guidelines may put more people on statins than need them. Others may require high-intensity rather than moderate approaches.
 
I may be naive, but I also wonder about a ticking time bomb of risk below the age of 40 years. Are the guidelines missing younger people who might benefit even more from therapy?

All this said, I applaud the committee. The road taken-evidence, evidence, and more evidence-is the right one. If there is more to be mined from additional predictors of risk, ie, specific biomarkers, how about focused and more frequent updates on the evidence for/against those predictors?
 
Ten years is a long time to wait. Finally, I hope the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (aka, JNC 7) is listening. You have some paradigm shifting recommendations that you have been sitting on for far too long. Note: it can be done!

I hope you are ready to change how we treat hypertension.   

Source: Stone NJ, Robinson J, Lichtenstein AH, et al. 2013 ACC/AHA guideline on the treatment of blood cholesterol to reduced atherosclerotic cardiovascular risk in adults. J Am Coll Cardiol. 2013.  doi:10.1016/j.jacc.2013.11.002.(FULL TEXT )