Mean systolic blood pressure was reduced from 166.7 mm Hg to 144.7 mm Hg ( -12.7 % ) within 24 hours in the antihypertensive treatment group and from 165.6 mm Hg to 152.9 mm Hg ( -7.2 % ) in the control group within 24 hours after randomization ( difference , -5.5 % [ 95 % CI , -4.9 to -6.1 % ] ; absolute difference , -9.1 mm Hg [ 95 % CI , -10.2 to -8.1 ] ; P < .001 ) .