 Sample size calculation and interim analysis The primary outcome was a composite in-hospital adverse outcome, including the death, stroke, permanent paraplegia or semi- paralysis during the hospitalization, and renal failure requiring hemodialysis at discharge. Bashir et al reported that the incidence of comprehensive nosocomial severe prognostic adverse events of ABAD was 45.2. Assume that the incidence of severe prognosis adverse event in comprehensive hospital after intensive blood pressure control could be reduced to 30, so a total of 322 subjects enrolled in the study are sufficient to find the difference statistically between two groups through the appropriate software calculation under the power of 0.8 and at the two-side test with α 0.05. Considering a dropout rate of 10, it is proposed to include 360 cases totally into the study. A formal interim analysis was conducted halfway during study enrollment. The overall type I error was controlled using an OBrien-Fleming spending function, with a final significance level of 0.05 for the primary end point. 