What type of cholesterol is primarily affected by atorvastatin's mechanism of action?

Atorvastatin primarily affects low-density lipoprotein (LDL) cholesterol, which is often referred to as "bad" cholesterol. Its mechanism of action involves inhibiting the enzyme HMG-CoA reductase, which is pivotal in the cholesterol synthesis pathway in the liver. By inhibiting this enzyme, atorvastatin reduces the production of cholesterol, leading to an increase in the uptake of LDL from the bloodstream into the liver. This mechanism results in lower circulating levels of LDL cholesterol, thereby reducing the risk of cardiovascular diseases associated with high LDL levels.

While atorvastatin can have some effects on other types of lipoproteins, including potential moderate effects on triglycerides and a slight increase in high-density lipoprotein (HDL or "good" cholesterol), the primary and most significant impact is on reducing LDL cholesterol levels. This makes LDL the primary focus when considering the therapeutic effects of atorvastatin.