J-shaped relationship between cardiovascular risk and efficacy of intensive blood pressure reduction: A post-hoc analysis of the SPRINT trial

BACKGROUND: In the 2017 ACC/AHA hypertension guidelines, a 10-year risk of more than 10% is considered for initiation of intensive blood pressure reduction. The current study aimed to determine which cut off limit of cardiovascular risk for starting intensive blood pressure reduction is beneficial. DESIGN: A Secondary Analysis of Systolic Blood Pressure Intervention Trial (SPRINT). METHODS: Data from the SPRINT Trial was obtained from the NHLBI Data Repository Center. In the SPRINT, non-diabetic participants with SBP of ≥ 130 mmHg were randomly assigned to intensive and standard treatment arms with SBP targets of < 120 and < 140 mmHg, respectively. This study analyzed data from non-diabetic participants less than 75 years of age without cardiovascular or chronic kidney disease. The primary composite outcome was myocardial infarction, and other acute coronary syndromes, stroke, heart failure, or death from cardiovascular causes. Cox regression models were used to examine the risk of the occurrence of the SPRINT primary composite outcome. To identify the relationship between BP values and the log hazards, natural cubic spline functions were performed. RESULTS: In the analysis, 4292 patients were enrolled. The results demonstrated a clear J-shaped relationship between the effect of intensive blood pressure control and the risk of CVD events and 10-year Framingham cardiovascular risk levels at a cut-off limit of approximately <7%. CONCLUSIONS: This post-hoc secondary analyses of the SPRINT trial showed that a cut off value of more than 7% may be useful in selecting patients suitable for initiation of blood pressure reduction.