Blood pressure and mortality after percutaneous coronary intervention: a population-based cohort study

Revascularization procedures, including percutaneous coronary intervention (PCI), for coronary artery disease (CAD) are increasingly performed in Korea. However, studies on blood pressure control targets in these patients remain insufficient. To assess the relationship between baseline blood pressure and all-cause mortality in CAD patients who underwent PCI. A population-based retrospective cohort study based on the national claims database of the Korean National Health Insurance System, which represents the entire Korean population. A total 38,330 patients with a history of PCI for CAD between 2005 and 2008 were recruited and followed up for all-cause mortality until December 31, 2017. Baseline systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured, and they were classified into eight SBP and DBP groups each. The hazard ratios (HRs) for all-cause mortality were measured for each group. The pattern of SBP and DBP in this population followed a J-curve relationship for all-cause mortality, with the nadir point at 119 and 74 mmHg, respectively. In subjects aged > 60 years, high SBP (≥ 160 mmHg) and high DBP (≥ 90 mmHg) were significantly related to death. Moreover, in subjects aged > 60 years, low DBP (< 70 mmHg) was significantly related to mortality. There is a J-curve relationship between baseline blood pressure and all-cause mortality in patients who underwent PCI, and intensive lowering of blood pressure may be beneficial for these patients. However, the elderly population needs more attention as excessive BP lowering, particularly DBP, could instead increase the risk of death.