I am not aware of any imaging study showing a decrease in atherosclerosis under statin treatment without a change in cholesterol levels, can you please reveal the source of this statement?

Hello Vivian,

this could be plausible for different reasons:

There is a wide range of risks factor beyond cholesterol affecting risk of atherosclerosis: smoking, high blood pressure, family history of CVD etc. The positive/negative effect of cholesterol on atherosclerosis is still ob debate.

I really recomand to read the study from  Petursson et al. (2012) Is the use of cholesterol in mortality risk algorithms in clinical guidelines valid? Ten years prospective data from the Norwegian HUNT 2 study.

The Hunt Study is also dealing with the controversity of cholesterol on CVD risks.

In any case you can contact me, if you have any further questions.

How is the athesrosclerosis reduction calculated in this review? is it estimated by LDL/HDL ratio? if yes, maybe the answer is that the sum of LDL+HDL still the same, but the LP profile change (decrease of LDL and increase of HDL cholesterol due to CETP inhibition)

More of that, statin inhibit oxidation of atherogenic LP beside other effects, that I invite you to check them (if you want) in the joined file, just to say that decreasing atherosclerosic index doesn't depend only on cholesterol synthesis, but also on other linked mechanisms

Article Statins and Metabolism of High Density Lipoprotein

Article Statins: Mechanism of action and effects

Statins have pleotropic properties encompassing anti inflammatory effects, countering of smooth muscle proliferation and prothrombosis. It has been reported to also cause some blood pressure reduction. These ameliorate atherosclerosis even if hypolidaemic effect is not great

Hi, Vivian. 

This article will probably answer your question.

http://circ.ahajournals.org/content/129/25_suppl_2/S1

There is a variable response for patients who are taking statins . Some people do not respond at all . There is a world wide agreement on the anti-inflammatory effect of statins . Since the essence of atherosclerosis is inflammation , this regression in the process is easily explained by the use of statins.

Perhaps what you were reading was suggesting that there are no "additional" blood cholesterol reductions, which is true beyond 4-6 weeks after starting and continuing a statin.

Atherosclerosis is dependent on a variety of factors, the most relevant in this case being the absolute LDL cholesterol concentration. A lower but unchanging absolute LDL cholesterol concentration will typically cause a lower rate of progression (or even regression) compared to a higher, stable LDL cholesterol concentration, all things else being equal.

It is also very likely that people treated for a period of time with statins, who then stop their statins, will have a lower absolute burden of atherosclerosis than those who never went on a statin in the first place, due to the impact of the period of time on the statin on atherosclerosis. Again this would require all other factors influencing atherosclerosis to be balanced between patients overall.

Thank you all for your answers. I have also checked with one of my professors who has said that statins have anti-inflammatory actions that do not depend on their lipid-lowering effects, hence explaining the scenario above.