Abstract P179: The Magnitude, And Not Direction, Of Blood Pressure Change Influences The Risk Of Serious Adverse Events In SPRINT

Abstract

Background: The landmark Systolic Blood Pressure Intervention Trial (SPRINT) showed that more intensive systolic blood pressure treatment (SBP < 120 mm Hg) was associated with lower risk for cardiovascular events and mortality but higher risk for serious adverse events (SAEs). However, it is unclear if the magnitude and/or the direction of the BP change determines SAE risk. In this study, we aim to determine how the magnitude and direction of BP change impacts SAE risk. Methods: This is a secondary analysis of 7922 participants in SPRINT. Time-varying Cox proportional hazards models were used to explore the relationship between visit-to-visit BP change and SAE risk. BP change was categorized using five intervals: 1) decreases ≥30 mm Hg, 2) decreases 10-29 mm Hg, 3) increases or decreases <10 mm Hg (reference category), 4) increases 10-29 mm Hg, and 5) increases ≥30 mm Hg. Additional variables adjusted for in the model included: age, gender, race, estimated glomerular filtration rate, treatment group, and baseline atherosclerotic cardiovascular disease (ASCVD) risk. Hypotension was excluded as an SAE to prevent bias in SAE risk in the large BP decrease category. Results: The hazard ratio (HR) for SAEs compared to the minimal BP change category was greatest for BP increases above 30 mm Hg (HR = 1.62, 95% confidence interval [1.30, 2.01]). However, the HR was similar for sharp BP decreases over 30 mm Hg (HR = 1.52 [1.23, 1.87]). Milder BP increases and decreases were associated with lower SAE risk (HR = 1.18 [1.06, 1.32] and HR = 1.10 [0.98, 1.22] for BP changes 10 to 30 mm Hg and -30 to -10 mm Hg, respectively). There were no significant interactions between BP change, intensive treatment, and baseline ASCVD risk. Conclusions: SAE risk was similar for similarly sized increases and decreases in BP between visits, with higher magnitude changes associated with higher SAE risk. When accounting for the magnitude of BP change, no significant effect of intensive treatment or baseline ASCVD risk was found.