Pravastatin inhibition of carotid intima-media thickness progression is not related to the extent of cholesterol reduction. The CAIUS Study

The Carotid Atherosclerosis Italian Ultrasound study (CAIUS) is a multicenter, parallel group, double-blind clinical trial, performed in 305 asymptomatic, moderately hyper-cholesterolemic patients, which demonstrated an inhibitory effect of pravastatin on the carotid intima-media thickness (IMT) progression. In the present post-hoc analysis of the CAIUS study we investigated whether the effect of pravastatin is related to the hypocholesterolemic effect of the drug. In the overall group of patients (placebo and pravastatin treated) covariance analysis showed that while the treatment was significantly related to the reduction of IMT progressione, the IMT progression did not correlate with the extent of LDL-C lowering. The pravastatin treated group was then stratified into quartiles of LDL-C lowering. In all quartiles, independently on the extent of response in terms of LDL-C lowering, reduction of IMT progression was observed. No significant difference was found among quartiles and no trend could be identified. Finally when treated patients were subdivided into responders (ΔLDL-C>10%) or non-responders (ΔLDL-C≤10%) the two group showed similar pattern of response in terms of inhibition of IMT progression. We conclude that the effect of pravastatin on the IMT progression rate is independent on the hypocholesterolemic effect of the drug.