The African American Study of Kidney Disease: do these results indicate that 140/90 mm hg is good enough?

Current national guidelines recommend aggressive lowering of blood pressure (< 130/80 mm Hg) in patients with chronic kidney disease (CKD). In this paper, we summarize recent clinical trial data evaluating the effect of lower blood pressure goals on renal outcomes. The epidemiologic data relating blood pressure to progression of kidney disease, the Modification of Diet in Renal Disease (MDRD) study (in patients with > 1 g proteinuria/d), and meta-analyses of angiotensin-converting enzyme (ACE) inhibitor clinical trials all support lower blood pressure goals in CKD patients, particularly those with proteinuria. The African American Study of Kidney Disease and Hypertension (AASK) supports lower blood pressure goals in terms of reduction of proteinuria, but demonstrates no additional benefit for clinical renal outcomes. Similarly, the second Ramipril Efficacy in Nephropathy study (REIN-2) shows that in patients with proteinuric nondiabetic renal disease who are receiving ACE inhibitors, a lower than usual blood pressure goal does not improve renal outcomes. However, there are limited clinical trial data evaluating the effects of low blood pressure on the increased cardiovascular risk seen in patients with CKD. Pending further clinical studies, current recommendations to target tight blood pressure control (< 130/80 mm Hg) in patients with CKD appear reasonable.