Intensive blood pressure treatment in coronary artery disease: implications from the Systolic Blood Pressure Intervention Trial (SPRINT)

To investigate the optimal blood pressure (BP) in patients with coronary artery disease (CAD), we conducted subgroup analysis using SPRINT data. The study sample included 1206 participants with CAD (of whom 692 underwent coronary revascularization) and 8127 participants without CAD. Participants were randomized into two groups (systolic BP target of 140 mm Hg vs. 120 mm Hg). The primary outcome was a composite of cardiovascular events. After a median follow-up of 3.9 years, the hazard ratios (HRs) for the primary outcome were 0.65 (95% confidence interval (CI) 0.53-0.79) and 1.05 (95% CI 0.76-1.46) among those in the non-CAD and CAD subgroups, respectively (P value for interaction 0.02). Intensive BP treatment was a protective factor for all-cause death (HR 0.60, 95% CI 0.37-0.96) in the CAD subgroup, compared with standard BP treatment. The HRs (95% CI) for stroke were 3.57 (1.17-10.85) and 1.03 (0.29-3.62) among those in the coronary revascularization and non-revascularization subgroups, respectively (P value for interaction 0.13). For safety events, intensive BP treatment increased the risk of hypotension (HR 2.00, 95% CI 1.06-3.79) and electrolyte abnormalities (HR 2.38, 95% CI 1.25-4.56) in the CAD subgroup, while the risk of serious adverse events did not increase (HR 1.03, 95% CI 0.88-1.20). These results suggest that positive benefits from intensive BP treatment might be attenuated in patients with CAD who are under better secondary prevention. The risk of stroke might increase at the systolic BP target of 120 mm Hg in case of coronary revascularization, although the confidence interval was wide.