Research Studies on BP control slows the progression of CKD
What studies have demonstrated that BP control slows the progression of CKD?
Multiple observational studies show that individuals with lower BPs have better overall kidney outcomes and slower progression to ultimate kidney failure.
However, it is important to demonstrate this effect through a randomized clinical trial looking at kidney end points with different BP goals. For instance, if patients are randomized to a higher versus lower BP, do the patients in the lower BP group have slower progression to kidney failure?
The answer to this question is, No. In large studies including the Modification of Diet in Renal Disease (MDRD) study, African American Study of Kidney Disease and Hypertension (AASK), Ramipril Efficacy in Nephropathy-2 (REIN-2) Study as well as in SPRINT, lower BP goals failed to slow the progression of kidney failure. This was confirmed in a 2016 meta-analysis of 613,815 patients and 123 studies.
Every 10-mm Hg reduction in systolic BP significantly reduced the risk of major cardiovascular disease events (RR 0.80, 95% CI 0.77 to 0.83), coronary heart disease (RR 0.83, 95% CI 0.78 to 0.88), stroke (RR 0.73, 95% CI 0.68 to 0.77), and heart failure (RR 0.72, 95% CI 0.67 to 0.78), which, in the populations studied, led to a significant 13% reduction in all-cause mortality (RR 0.87, 95% CI 0.84 to 0.91).
However, the effect on kidney failure was not significant (RR 0.95, 95% CI 0.84 to 1.07).
At this time, we do not have compelling evidence that lowering BP preserves kidney function, but given its powerful effect at modulating risk of stroke, heart disease, and total mortality, this should not dissuade from careful and thoughtful BP management.
