Acute Declines in Renal Function during Intensive BP Lowering: Implications for Future ESRD Risk

Area of Science:

• Nephrology
• Cardiovascular Medicine
• Clinical Trials

Background:

• The acceptable level of renal function decline during intensive blood pressure (BP) management is not well-defined.
• Understanding the association between acute kidney function changes and end-stage renal disease (ESRD) risk is crucial for managing chronic kidney disease (CKD).

Purpose of the Study:

• To investigate if acute declines in estimated glomerular filtration rate (eGFR) during intensive BP lowering in CKD patients are linked to an increased risk of ESRD.
• To compare the risk of ESRD associated with varying degrees of eGFR decline under strict versus usual BP control strategies.

Main Methods:

• Retrospective analysis of 899 participants from the African American Study of Kidney Disease and Hypertension (AASK) and 761 from the Modification of Diet in Renal Disease (MDRD) Trial.
• Patients were categorized by percentage decline in eGFR (<5%, 5% to <20%, or ≥20%) between randomization and months 3-4.
• ESRD incidence was the primary outcome, analyzed in relation to BP control intensity (strict vs. usual).

Main Results:

• A 5% to <20% eGFR decline during intensive BP lowering was not associated with higher ESRD risk in either AASK or MDRD Trial.
• Conversely, a 5% to <20% eGFR decline in the usual BP arm was linked to increased ESRD risk in both trials.
• An eGFR decline of ≥20% was associated with a higher risk of ESRD under both strict and usual BP control regimens.

Conclusions:

• Acute eGFR declines of 20% or more during intensive BP lowering identify patients at significantly higher risk for adverse renal outcomes.
• Moderate eGFR declines (5% to <20%) during intensive BP lowering appear safe and do not increase ESRD risk, supporting the benefits of strict BP control.