BP Reduction, Kidney Function Decline, and Cardiovascular Events in Patients without CKD

Area of Science:

• Cardiology
• Nephrology
• Clinical Trials

Background:

• The Systolic Blood Pressure Intervention Trial (SPRINT) compared intensive systolic blood pressure (BP) treatment (<120 mm Hg) to standard treatment (<140 mm Hg).
• Intensive treatment reduced cardiovascular events but increased kidney function decline.
• This study focuses on patients without chronic kidney disease (CKD).

Purpose of the Study:

• To evaluate the association between mean arterial pressure (MAP) reduction, kidney function decline, and cardiovascular events in SPRINT participants without CKD.
• To determine the risks and benefits of intensive BP lowering based on MAP reduction levels.

Main Methods:

• Patients in the intensive treatment group were categorized by MAP reduction (<20, 20 to <40, ≥40 mm Hg).
• Kidney function decline was defined as a ≥30% reduction in eGFR to <60 ml/min/1.73 m².
• Cardiovascular events were secondary outcomes.
• Propensity score matching compared intensive vs. standard treatment groups.

Main Results:

• In the intensive group, 34% had MAP reduction <20 mm Hg, 56% had 20 to <40 mm Hg, and 9% had ≥40 mm Hg.
• Adjusted hazard ratios for kidney function decline increased with greater MAP reduction (2.10 for 20-40 mm Hg, 6.22 for ≥40 mm Hg).
• Number needed to harm for kidney decline was 16 for MAP reduction ≥40 mm Hg, while number needed to treat for cardiovascular events was 95.

Conclusions:

• Greater MAP reduction in the intensive treatment arm of SPRINT was associated with a higher incidence of kidney function decline.
• Intensive BP treatment may be less favorable when substantial MAP reduction is required to achieve target BP goals, particularly concerning kidney health.