Prior to SPRINT, the largest RCTs addressing the effects of intensive BP control in CKD were MDRD,97 The primary outcome of these 3 trials was progression of kidney disease. During the trial phase, when the chapter 3 www.kidney-international.org participants were under their respective randomized in- terventions, none of these trials showed bene ts or harms on kidney function by intensive BP lowering in the primary analysis of the entire cohort. A caveat of MDRD and AASK is that both trials targeted mean arterial BP (MAP, calculated as DBP 1/3  pulse pressure), rather than SBP or DBP. The lower target was a MAP of <92 mm Hg (equivalent, for example, to 125/75 mm Hg, 140/68 mm Hg, 160/58 mm Hg, or many other combinations of SBPs and DBPs), whereas the higher target was a MAPof <107 mm Hg (equivalent to 140/90 mm Hg, 125/98 mm Hg, etc.). Further, the MAP targets varied in MDRD, depending on the age of the patients.136 A meta-analysis in 2011 conducted by the ERT of the KDIGO 2012 BP guideline found only these 3 studies (MDRD, AASK, and REIN-2) pertinent to the discussion of whether a lower BP target reduced the risk of progression to kidney failure in the presence of proteinuria. They concluded that the evidence was inconclusive.137 Similarly, the current ERT review found no effect modi cation according to the presence of proteinuria (Supplementary Table S1297 ). 