In the placebo group , significantly greater progression of the mean IMT [ from 0.51 mm ( S.D. 0.07 ) at baseline to 0.53 mm ( S.D. 0.08 ) at 6 months , P = 0.044 ] and PWV ( from 12.2 m/s ( S.D. 1.6 ) at baseline to 12.6 m/s ( S.D. 1.3 ) , P = 0.028 ] were observed .