I seem to remember a post on this topic recently but thought wouldn't hurt to repeat. The essence of this study in Cardiovascular Diagnosis & Therapy, June 2016 is:
"Therefore, in brief: (I) CAC progression is an independent predictor of events; (II) statins promote plaque regression; and (III) statins promote CAC progression. These paradoxical results are puzzling and warrant the conduction of further studies aimed at the pathophysiological and clinical discrimination between plaque volume progression and CAC progression. One of the potential explanations might be that conventional reading of CAC studies does not make a distinction between spotty calcifications and dense calcium."
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4880753/
So based upon this if a person is going on statins, serial CAC scores would not seem to be valuable. An initial one yes. That would tell them their real risk at that point in time much better that all their lipid ratios and numbers. Afterward it would seem that tracking plaque progression/regression via serial CIMTs would be the better strategy to understand the efficacy of the treatment.
The thinking is that the statins have a beneficial effect on the plaque by stabilizing it with calcium, hence the higher scores.
