Concentration of ApoB-carrying lipoproteins in the bloodstream as the driver of heart disease is one of the most strongly proven facts in medicine. Statins are proven to lower LDL (a close-enough substitute for ApoB in most situations) by about 30%. I can't look at the study now, but most likely it's a situation where patients' cholesterol has not been lowered enough by medication to make a meaningful difference. If you have an LDL of 160, statins aren't going to be sufficient. The issue is doctors/patients not targeting a sufficiently low cholesterol level.