In denervation subjects , the 12-month office systolic BP ( SBP ) change was greater than that observed at 6 months ( -15.5 24.1 mm Hg vs.-18 .9 25.4 mmHg , respectively ; p = 0.025 ) , but the 24-h SBP change was not significantly different at 12 months ( p = 0.229 ) .