Complex Exercise Intervention to Normalize Blood Pressure and Nocturnal Dipping in Patients With Hypertension (END-HT)

Effectiveness of a Complex Exercise Intervention to Normalize Blood Pressure and Its Nocturnal Dipping in Patients With HyperTension in Primary Care: a Randomized-controlled Trial

Background: Non-dipping hypertension(HT) (as defined by lack of decrease in systolic blood pressure (BP) by 10% during sleep) predicts cardiovascular events and mortality; however, there is a lack of evidence based treatment for non-dipping HT. While exercise is recommended to management HT, its effect on dipping status is not known. There is a lack of trials describing the relationship of exercise and blood pressure in Chinese.

Method: This will be a two-arm randomized controlled trial in which Chinese non-dippers (n= 198) will be randomized to an exercise program plus usual care or to usual care by stratified randomization. The randomization sequence is blinded to the investigators and allocation is disclosed only after valid consent. The exercise program utilizes various motivational techniques to enhance exercise maintenance.

Study Overview

• Status: Completed
• Conditions: Hypertension
• Intervention / Treatment: Behavioral: EIM intervention group

• Study Type: Interventional
• Enrollment (Actual): 198
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Hong Kong
  • Hong Kong, Hong Kong
    • Lek Yuen Clinic

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• SBP non-dippers
• self-reported exercise intensity and duration less than the World Health Organization recommendation, which is exercise of moderate intensity less than 150minutes/week OR exercise of vigorous intensity of less than 75 minutes/week
• Used any mobile apps on their phone (because the intervention involve use of apps to monitor and remind regular exercise)

Exclusion Criteria

• Patients with diagnosed chronic obstructive lung disease and recent stroke (within last 12 months) because other evidence-proven and well-structured programmes are implemented for these patients in the hospital authority in Hong Kong

• Occupational drivers - because they need to hold their arm still during ABPM and this may be hazardous for drivers

  • night-time workers
  • diagnosed Obstructive Sleep Apnea
• Patients on anti-coagulants - because ABPM may induce bruises
• Patients on 3 or more medications for hypertension (on maximum tolerable doses) - these patients may have secondary HT and represent a different spectrum of organic diseases
• Patients with SBP >180mmHg or DBP >110mmHg - drug titration is not allowed during the 12-week program and these patients need early drug treatment

• Patient with DM - these patients will be arranged to have another EIM program especially designed for their DM.

  • Patients with active spinal cord compression or spinal radiculopathy because they may not be suitable to join some exercise
  • patients with atrial fibrillation are excluded because these patients have increased BP variability and may have different dipping behaviour
  • patients with metallic implants or pacemakers are excluded as they are not suitable for MRI

• To maximize safety of patients, patients who are relatively contraindicated according to AHA will also be excluded

  • acute myocardial infarction in last 6 months
  • ongoing angina
  • uncontrolled cardiac arrhythmia
  • acute diseases including known active endocarditis/acute pulmonary embolism, pulmonary infarction, deep vein thrombosis, acute aortic dissection, acute myocarditis
  • known aortic stenosis
  • known heart failure
  • known obstructive left main coronary artery stenosis
  • uncontrolled ventricular rates
  • complete heart block
  • known hypertrophic obstructive cardiomyopathy
  • mental impairment that limit co-operation
  • resting blood pressure with systolic blood pressure >180mmHg or diastolic blood pressure >110mmHg
  • known anemia with hemoglobin level less than 11gm/dL
  • known uncorrected electrolyte imbalance, and
  • known uncontrolled hyperthyroidism.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: EIM group; patients with Hypertension (HT) will be recruited by a trained nurse when the patient attends the yearly to bi-yearly complication screening program called the risk assessment and management program (RAMP) program. This program is provided to all patients with HT, who are seen in the Government-funded primary care clinics in Hong Kong. The nurse will encourage the patient by motivational interviewing techniques and prescribe exercise. Combined exercise skills will be taught in the 12-week weekly exercise classes by certified physical trainers. Peer support is encouraged during and after the 12-week program. Regular feedback, prompting and problem solving will be provided by the nurse at 3m, 6m, and 12m. Exercise level will be monitored by validated wrist trackers to feedback participants, nurse and physical trainer by mobile apps and website. Resources to exercise will be made known to patients by apps, website and healthcare professionals.	Behavioral: EIM intervention group; As in arm description
No Intervention: usual care; There is no extra intervention to patients allocated in this arm, except that they receive information and advice on lifestyle changes including benefits from exercise from the nurse at recruitment as stated above. Participants in both arms will have no changes in medication within the first 12-week to determine the BP difference between the two groups. In Hong Kong, patients have unlimited access to emergency department and general outpatient services. All patients with HT receive RAMP program counselling and screening every 1-2 years. These are not limited by the current trial.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
systolic blood pressure(SBP) dipping status	as defined by a lack of SBP drop of more than 10% during sleep, as detected by ambulatory blood pressure measurements (ABPM)	at 12-week, after the EIM program

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
daytime, night-time, 24-h SBP, and DBP	as detected on ABPM discussed above	baseline (before the 12-week program ), at 12 weeks and 12 months after recruitment
serum lipid profile	this includes serum total cholesterol, triglyceride , low-density lipoprotein and high-density lipoprotein	baseline (before the 12-week program ), at 12 weeks and 12 months after recruitment
body mass index	weight and height will be combined to report BMI in kg/m^2	baseline (before the 12-week program ), at 12 weeks, at 24 weeks and 12 months after recruitment
office blood pressure	office blood pressure will be measured 3 times and the last 2 will be averaged as the outcome	baseline (before the 12-week program ), at 12 weeks, at 24 weeks and 12 months after recruitment
The Chinese version of international Physical Activity Questionnaire - short form (IPAQ-SF)	a validated questionnaire to detect exercise level; The questionnaire can provide the amount of time the participant spend on moderate or vigorous physical activities. The amount of energy spent can be calculated (metabolic equivalent of task; MET). For example, high level of exercise can be defined as a minimum total physical activity of at least 3000 MET minutes a week. The higher the MET, the higher the exercise level	baseline (before the 12-week program ), at 12 weeks, at 24 weeks and 12 months after recruitment
systolic blood pressure(SBP) dipping status	as defined by a lack of SBP drop of more than 10% during sleep, as detected by ambulatory blood pressure measurements (ABPM)	measured at baseline and 12 months
body fat percentage	body fat percentage	baseline (before the 12-week program ), at 12 weeks, at 24 weeks and 12 months after recruitment
serum fasting glucose level	serum fasting glucose level	baseline (before the 12-week program ), at 12 weeks and 12 months after recruitment
serum creatinine level	serum creatinine level that reflects renal function	baseline (before the 12-week program ), at 12 weeks and 12 months after recruitment
waist circumference	waist circumference	baseline (before the 12-week program ), at 12 weeks and 12 months after recruitment
serum high sensitive C-reactive protein	serum high sensitive C-reactive protein that reflect the degree of inflammation	baseline (before the 12-week program ), at 12 weeks and 12 months after recruitment
MRI (proton density fat fraction)	MRI liver to detect the degree of liver steatosis	baseline (before the 12 week program), at 12 weeks
Pittsburgh Sleep Quality Index(PSQI)	a validated questionnaire to detect sleep quality; possible "global" score include can range from 0 to 21. A global score of 5 or more indicates poor sleep quality; the higher the score, the worse the quality.	baseline (before the 12-week program ), at 12 weeks, at 24 weeks and 12 months after recruitment
STOP-BANG (Snoring, Tiredness, Observed apnea, Blood pressure, Body mass index, Age, Neck circumference and Gender) questionnaire	a validated questionnaire to detect presence of sleep apnea; any 3 positive items from the 8 questions as having risk of OSA; the higher the number of positive items, the higher the risk	baseline (before the 12-week program ), at 12 weeks, at 24 weeks and 12 months after recruitment

Collaborators and Investigators

• Sponsor: Chinese University of Hong Kong

Publications and helpful links

General Publications

• Lee EK, Zhang DD, Yip BH, Cheng J, Hui SS, Yu EYT, Leung M, Chu WCW, Mihailidou AS, Wong SY. Exercise Intervention to Normalize Blood Pressure and Nocturnal Dipping in HyperTensive Patients (END-HT): Protocol of a Randomized Controlled Trial. Am J Hypertens. 2021 Aug 9;34(7):753-759. doi: 10.1093/ajh/hpab019.

Study record dates

Study Major Dates

• Study Start (Actual): September 15, 2021
• Primary Completion (Actual): September 30, 2025
• Study Completion (Actual): September 30, 2025

Study Registration Dates

• First Submitted: April 16, 2019
• First Submitted That Met QC Criteria: April 18, 2019
• First Posted (Actual): April 23, 2019

Study Record Updates

• Last Update Posted (Estimated): December 15, 2025
• Last Update Submitted That Met QC Criteria: December 8, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Hypertension
• Other Study ID Numbers: NTEC-2019-0264

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: Will be made available on request from investigators

Drug and device information, study documents

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