Guiding Hypertension Management Using Different Blood Pressure Monitoring Strategies (GYMNs study): comparison of three different blood pressure measurement methods: study protocol for a randomized controlled trial

BACKGROUND: Home blood pressure (BP) and unattended automated BP (uAOBP) monitoring have been recommended by guidelines for the care of hypertensive subjects. However, BP measurements in the peripheral arteries cannot serve as direct substitutes for their central counterparts. Moreover, the comparative effectiveness and safety of BP-guided strategies using these BP measuring devices have never been evaluated. METHODS/DESIGN: Patients with uncontrolled or newly diagnosed hypertension aged 20-90 years will be recruited via outpatient clinics and allocated into three arms by stratified randomization (baseline systolic BP 130-155 mmHg and 155-180 mmHg): home BP, uAOBP, and central BP-guided treatment. At each scheduled visit to the clinic, a patient's BP will be measured by each of the three methods of measuring BP. The blood pressure from three different methods will be confirmed available at each visit. Patients and physicians will be blinded to the allocated interventions because they will use measured BP values in the clinic through a standardized report format. A common BP target for systolic blood pressure (SBP) of 130 mmHg is adopted for these BP-guided strategies. The primary outcome is the change of 24-h mean ambulatory SBP at 3 months. A key secondary outcome is to determine the percentage achieving their target BPs at 3 months and the decrease of left ventricular mass at 12 months. DISCUSSION: To our knowledge, this is the first prospective double-blind randomized controlled trial to assess the optimal guiding strategy for hypertension. It will help to define which BP monitoring method is the most effective for guiding the clinical management of hypertension. It will provide good evidence to support future guideline recommendations for BP monitoring devices. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03578848 . Registered on 4 June 2018.