Stratified analysis by cholestanol-to-cholesterol ratio tertiles confirmed this effect modification : atorvastatin reduced the risk of reaching the primary endpoint in the first tertile ( hazard ratio [ HR ] : 0.72 ; p = 0.049 ) , but not the second ( HR : 0.79 ; p = 0.225 ) or third tertiles ( HR : 1.21 ; p = 0.287 ) .