J Curve in Patients Randomly Assigned to Different Systolic Blood Pressure Targets: An Experimental Approach to an...

Area of Science:

• Cardiology
• Clinical Trials
• Hypertension Research

Background:

• Low systolic blood pressure (SBP) is associated with increased cardiovascular event risk, a phenomenon known as the J-curve.
• Understanding the relationship between on-treatment SBP levels and adverse outcomes is crucial for managing hypertensive patients.

Purpose of the Study:

• To assess the association between on-treatment systolic blood pressure (SBP) levels and cardiovascular events and all-cause mortality.
• To investigate if the J-curve phenomenon persists across different SBP treatment targets.

Main Methods:

• Pooled data from two large randomized trials involving hypertensive patients at high cardiovascular risk.
• Patients were randomized to intensive (SBP<120 mm Hg) or conventional (SBP<140 mm Hg) treatment.
• Hazard ratios for mortality and cardiovascular events were plotted against mean on-treatment SBP using natural cubic splines.

Main Results:

• The analysis included 13,946 patients with 194,875 SBP measurements.
• A J-curve association was observed for both cardiovascular events and all-cause mortality, with a nadir just below the SBP target.
• Patients in the lowest SBP stratum had higher rates of traditional cardiovascular risk factors and events.

Conclusions:

• Low on-treatment SBP levels are independently associated with increased cardiovascular events and all-cause mortality.
• The J-curve phenomenon aligns with the SBP target, suggesting the relationship is consistent across different treatment goals.
• Randomized clinical trials are essential for establishing the true benefit or risk of intensive blood pressure-lowering strategies.