Objective: Echolucency of the carotid intima-media thickness (CIMT) is thought to reflect a high probability of lipid infiltration and is associated with increased cardiovascular risk factor levels, morbidity, and mortality. The present study assessed the effect of statins on echolucency of the common CIMT.

Methods: Ultrasound images from the far wall of the common carotid artery were used from 984 individuals of the METEOR trial. Echolucency was measured as the grey scale median (GSM). Lower GSM values indicate a higher lipid content in the arterial wall. The primary endpoint was the difference in annual rate of change in GSM between rosuvastatin and placebo treatment during 2 years of follow-up.

Results: Two-year change GSM did not significantly differ between rosuvastatin and placebo in the total population: mean difference 1.13 (95% confidence interval [CI]: −1.00;3.25). The effect of rosuvastatin differed across quintiles of baseline GSM values (p for interaction 0.01). In the lowest quintile, i.e. in those with the largest amount of lipid infiltration, the difference in rate of change in GSM was 4.18 (95%CI: −0.23; 8.58). Increases in GSM (i.e. lipid removal from the CIMT) were significantly related to decreasing low-density lipoprotein cholesterol (LDL-C) levels in the lowest quintile, but not in the other quintiles (beta: 0.76 [95%CI: 0.26; 1.25]).

Conclusion: Rosuvastatin did not affect the echolucency of the arterial wall in all individuals. However, a potential effect of rosuvastatin on echolucency of the CIMT is most likely to be found in individuals with an echolucent, lipid-rich, arterial wall at baseline.