Which lipid profile change is desirable when using fibrates?

When using fibrates, the desirable change in the lipid profile is an increase in HDL levels. Fibrates primarily work by activating peroxisome proliferator-activated receptors (PPARs), which enhance the breakdown of triglycerides and promote the synthesis of apolipoproteins that are associated with HDL particles. This leads to an elevation in HDL cholesterol, often referred to as "good" cholesterol, which helps remove cholesterol from the bloodstream and reduces the risk of cardiovascular diseases.

While fibrates also have beneficial effects on lowering triglyceride levels significantly, the specific focus on increasing HDL levels is particularly important, as higher levels of HDL cholesterol are associated with a decreased risk of coronary heart disease. The other options mentioned do not accurately capture the primary beneficial effect of fibrates as it pertains specifically to HDL cholesterol; lowering LDL levels is more characteristic of statins, and an increase in triglycerides would be undesirable, while the action on total cholesterol is not as pronounced or targeted as the effect on HDL.