Optimal blood pressure target in the elderly: rationale and design of the HOW to Optimize eLDerly systolic Blood Pressure (HOWOLD-BP) trial

Background/Aims: The optimal systolic blood pressure (SBP) goal for elderly patients with hypertension, especially to reduce cardiovascular disease (CVD) incidence and improve outcome, is unclear. This study aimed to evaluate the beneficial effects of intensive treatment for hypertension on the incidence of CVD in elderly Korean patients. Methods: The HOW to Optimize eLDerly systolic Blood Pressure (HOWOLD- BP) trial is a multicenter, parallel- design, open-label, randomized controlled trial designed to evaluate whether intensive treatment (SBP <= 130 mmHg) will provide more benefits in lowering the incidence and mortality associated with CVD than standard treatment (SBP <= 140 mmHg) in elderly patients with hypertension aged >= 65 years. For this study, eleven university hospitals in Korea will enroll approximately 3,176 elderly patients with hypertension between 2019 and 2022. Patients will be requested to visit the clinic every 4 months for the first year and every 6 months thereafter for 36 months. Parameters, including clinic and home blood pressure, anthropometric and laboratory findings, and frailty assessments, will be collected according to the standardized protocol. The primary outcome is a composite of CVD (acute coronary syndrome, stroke, and heart failure) incidence and cardiovascular deaths. Results: As of December 2021, 1,655 participants had been enrolled in the study, including 831 patients in the standard group and 824 patients in the intensive group. Conclusions: The HOWOLD- BP trial is the first study performed in Korea to evaluate the beneficial effects of intensive blood pressure treatment on CVD in elderly patients with hypertension. The results of this study will help clarify the appropriate target SBP for this population.