Intensive Versus Standard Blood Pressure Lowering and Days Free of Cardiovascular Events and Serious Adverse Events: a Post Hoc Analysis of Systolic Blood Pressure Intervention Trial

Abstract

Background: Communication of the benefits and harms of blood pressure lowering strategy is crucial for shared decision-making. Objectives: To quantify the effect of intensive versus standard systolic blood pressure lowering in terms of the number of event-free days Design: Post hoc analysis of the Systolic Blood Pressure Intervention Trial Participants: A total of 9361 adults 50 years or older without diabetes or stroke who had a systolic blood pressure of 130–180 mmHg and elevated cardiovascular risk Interventions: Intensive (systolic blood pressure goal <120 mmHg) versus standard blood pressure lowering (<140 mmHg) Main Measures: Days free of major adverse cardiovascular events (MACE), serious adverse events (SAE), and monitored adverse events (hypotension, syncope, bradycardia, electrolyte abnormalities, injurious falls, or acute kidney injury) over a median follow-up of 3.33 years Key Results: The intensive treatment group gained 14.7 more MACE-free days over 4 years (difference, 14.7 [95% confidence interval: 5.1, 24.4] days) than the standard treatment group. The benefit of the intensive treatment varied by cognitive function (normal: difference, 40.7 [13.0, 68.4] days; moderate-to-severe impairment: difference, −15.0 [−56.5, 26.4] days; p-for-interaction=0.009) and self-rated health (excellent: difference, −22.7 [−51.5, 6.1] days; poor: difference, 156.1 [31.1, 281.2] days; p-for-interaction=0.001). The mean overall SAE-free days were not significantly different between the treatments (difference, −14.8 [−35.3, 5.7] days). However, the intensive treatment group had 28.5 fewer monitored adverse event–free days than the standard treatment group (difference, −28.5 [−40.3, −16.7] days), with significant variations by frailty status (non-frail: difference, 38.8 [8.4, 69.2] days; frail: difference, −15.5 [−46.6, 15.7] days) and self-rated health (excellent: difference, −12.9 [−45.5, 19.7] days; poor: difference, 180.6 [72.9, 288.4] days; p-for-interaction <0.001). Conclusions: Over 4 years, intensive systolic blood pressure lowering provides, on average, 14.7 more MACE-free days than standard treatment, without any difference in SAE-free days. Whether this time-based effect summary improves shared decision-making remains to be elucidated.