Using Night-time Blood Pressure to Treat Hypertension

Home Blood Pressure During Night-time Sleep as a Better Treatment Target for Patients With Hypertension: a Proof-of-concept Randomized Controlled Trial

Objectives: To examine the feasibility of conducting night-time home blood pressure(BP) monitoring (during sleep) and titration of medications in the evening. This will provide data for sample size calculation for the main trial, which will examine whether night-time BP is a better target than conventional daytime BP for hypertension management.

Hypothesis to be tested: night-time home BP monitoring(HBPM) and evening drug titration are acceptable to patients; and future main trial is feasible in terms of recruitment/dropout rate/medication adherence.

Design and subjects: This pilot randomized-controlled trial will recruit 78 patients with nocturnal hypertension (asleep systolic BP 120mmHg on ambulatory blood pressure monitoring(ABPM)). They will be allocated in 1:1 ratio to have their medication titrated in the evening according to night HBPM (Experimental group) or in the morning according to daytime HBPM (control group) respectively.

Instruments: ABPM/HBPM. Interventions: titration of the dose(s) of anti-hypertensive medications in the evening according to night HBPM (experimental group) and in the morning according to daytime HBPM (control group) every 4 weeks.

Main outcome measures: ABPM at baseline and at 6 months Data analysis and expected results: The rate of recruitment/dropout and adherence to night HBPM will be presented. The feasibility of HBPM will be assessed by the patients' adherence to HBPM and by patients' interviews. ANCOVA will be used to evaluate whether titration of medication can normalize BP levels. We expect patients to have a high adherence rate and that titration of evening doses of medications will better improve night-time BP on ABPM.

Study Overview

• Status: Completed
• Conditions: Hypertension
• Intervention / Treatment: Behavioral: treatment of BP by using night-time BP; Behavioral: treatment of BP by using daytime BP

• Study Type: Interventional
• Enrollment (Actual): 78
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Hong Kong
  • Hong Kong, Hong Kong
    • School of public health and primary care

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• diagnosed hypertension (HT) from clinical records
• nocturnal HT (night-time systolic blood pressure (SBP) during sleep ≥120 mmHg) and stage I hypertension (daytime SBP = 135-159mmHg)

Exclusion Criteria:

• patients with atrial fibrillation (many home blood pressure (BP) machines are not validated in these patients and these patients have greater BP variability)
• daytime office systolic BP ≥180 mmHg or diastolic BP ≥120 mmHg (regardless of nocturnal BP) because these patients need urgent BP treatment and it is not known if medications given in the evening are equally effective
• patients with known obstructive sleep apnoea because the night-time BP of these patients is predominately affected by the sleep apnoea
• patients with known stroke, ischemic heart disease, heart failure, kidney failure, peripheral vascular disease and diabetes mellitus because their daytime BP targets will be different
• dementia or psychiatric illness that impairs patients' ability to perform home blood pressure monitoring (HBPM) by themselves
• patients with end-stage malignancies
• nocturnal worker, because they will have a reverse BP pattern to other participants
• patients who sleep after 2am or wake up before 4am because these patients will not be asleep during night HBPM
• patients receiving ≥3 BP medications at maximal tolerated doses because there is little space for drug titration and these patients may have secondary HT representing another disease spectrum
• patients receiving anti-coagulants because ABPM can induce significant bruises (during repeated cuff inflations) in these patients.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: treatment by night-time BP; titrate drug treatment in the evening against night home blood pressure monitoring (HBPM) SBP (aiming SBP of <120 mmHg; intervention group)	Behavioral: treatment of BP by using night-time BP; titration of BP medications to target according to night-time SBP
Other: treatment by daytime BP; Usual care - titrate drug treatment in the morning against HBPM SBP (aiming SBP of <135 mmHg; control group)	Behavioral: treatment of BP by using daytime BP; titration of BP medications to target according to daytime SBP

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
the rate of recruitment	number of participants recruited per month during recruitment period	0 month to 18 month (anticipated recruitment period)
feasibility of home blood pressure (BP) measurement	the proportion of patients who can measure nocturnal BP successfully	0 month to 24 month (end of trial)
feasibility of repeated ambulatory blood pressure monitoring (ABPM)	the proportion of patients finished both ABPM	0 month to 24 month (end of trial)
dropout rate	number of participants drop-out from each arm	0 month to 24 month (end of trial)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
systolic BP (SBP) / diastolic BP (DBP) on ABPM	Mean daytime/night-time/24-hour SBP/DBP	taken at 0 month and 6 month for each patient
serum creatinine level	an assessment for renal function (the higher value suggest poorer renal function)	taken at 0 month and 6 month
lipid profile	low-density lipoprotein (LDL), high-density lipoprotein (HDL), Triglyceride (TG), total cholesterol (TC)	taken at 0 month and 6 month
microalbuminuria	the presence of microalbuminuria suggest renal damage	taken at 0 month and 6 month

Collaborators and Investigators

• Sponsor: Chinese University of Hong Kong

Study record dates

Study Major Dates

• Study Start (Actual): May 1, 2022
• Primary Completion (Actual): January 31, 2024
• Study Completion (Actual): February 28, 2024

Study Registration Dates

• First Submitted: August 29, 2021
• First Submitted That Met QC Criteria: September 1, 2021
• First Posted (Actual): September 2, 2021

Study Record Updates

• Last Update Posted (Actual): May 2, 2024
• Last Update Submitted That Met QC Criteria: April 30, 2024
• Last Verified: April 1, 2024

More Information

Terms related to this study

• Keywords: ABPM; hypertension; nocturnal hypertension
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypertension
• Other Study ID Numbers: 2021.253-T

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: will share data on responsible requests

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No