Hypertension Study

Project Plan

If you are on one type of blood pressure medication or none at all but have been diagnosed with high blood pressure you may be eligible for our study. This study is for adults with mild hypertension and compares a standard dose of a single type of BP medication to low-dose-quadruple therapy (LDQT). LDQT has four different types of blood pressure-lowering medications encapsulated into one single pill – irbesartan 37.5mg, amlodipine 1.25mg, indapamide 0.625mg and bisoprolol 2.5mg. All are approved by the Therapeutic Good Administration/ US Food and Drug Administration and currently prescribed to patients.

Each of the four medications are at a 1/4 of the usual strength and cover 4 different targets known to lower blood pressure. The advantage of this is that blood pressure is lowered more effectively with minimal side effects at the ultra-low dose. This medication is provided free of charge and couriered directly to your preferred address.

Even if you have been stable on treatment for some time it is useful to come in and have a thorough free check-up in a hypertension specialist clinic. Get a second opinion and check that your medication regimen is still working for you. As part of our screening process we do 24hr blood pressure monitoring which is commonly not done through GPs and this gives the most accurate measure of what your blood pressure is like during a typical day in your life. We also do blood and urine tests, an ECG and measure your blood pressure under our controlled conditions.

Hypertension affects 1 in 3 Australian adults aged 18 years and over (ie systolic or diastolic blood pressure is ≥135/85 mmHg). That’s 6 million people. Of these, more than two thirds have uncontrolled unmanaged high blood pressure (not taking medication). For each 20 mmHg reduction in systolic blood pressure, cardiovascular risk halves. So a relatively small reduction can make a massive difference to your health and life expectancy.

The research study is designed by doctors and medical researchers at The George Institute for Global Health and the University of Sydney. The National Chief Investigator of the study is Professor Clara Chow and the study is funded by non-commercial funding bodies.

Justine Chan, Alice Rothwell and Professor Markus Schlaich

I am Alice Rothwell, a graduate of UWA who has returned to Perth after working in research over east and abroad. My colleague, Justine Chan and I are research assistants working with Professor Markus Schlaich for UWA at the Royal Perth Hospital Medical Research Foundation. We are located on Murray Street in the CBD. We are working on the Quartet study in addition to other clinical blood pressure and diabetes studies. We are a hypertension specialist group working to improve the treatments available for people with high blood pressure.

Hypertension is the biggest killer world-wide with an estimated 10 million deaths per year directly attributable to uncontrolled blood pressure.

Hypertension comes in many forms: sometimes revealed during pregnancy, it is frequently associated with obesity and chronic kidney disease, and not rarely presenting itself in the emergency department with hypertensive crises and strokes. While much progress has been made to better understand the underlying causes and manage elevated blood pressure and its consequences, less than 50% of patients diagnosed with hypertension are adequately controlled. The presence of other cardiovascular and metabolic risk factors are important contributors to this scenario and therefore represent another major focus of our research. With our unique methodologies we are at the forefront of research in several of these areas.

The Dobney Hypertension Centre (DHC) is a collaborative venture between The University of Western Australia and Royal Perth Hospital. It is led by Professor Markus Schlaich, an international leader in research of high blood pressure, otherwise known as hypertension.

DHC is accredited as a Hypertension Excellence Centre by the European Society of Hypertension, and engages in high quality clinical research with the ultimate aim to better understand the mechanisms that lead to elevated blood pressure. Throughout the year, numerous clinical trials and research studies are run by the dedicated research team that aim to both improve health outcomes, and optimize the treatment of hypertension across the community.

Additional sub-study available

Specific to the Perth branch of the study is an optional additional imaging sub-study called HARMONY. Participants can receive 2 free tests that look at the heart structure and function;

  • Echocardiogram at Royal Perth Hospital
  • Cardiac MRI (Magnetic Resonance Imaging) at Advanced Diagnostic Imaging in Madeley

These scans are done at baseline and the 12mth time-point so are really for people who are committed to the year-long version of the study. The HARMONY sub-study aims to show that treatment with LDQT (low-dose-quadruple therapy) improves diastolic dysfunction and other markers of heart damage compared to standard therapy. This study is led by Dr. Riti Chetty, a cardiologist at Royal Perth Hospital.

Your Support

This study aims to further medical knowledge and may improve future treatment of hypertension.

You will be participating in a randomised controlled research project. Sometimes we do not know which treatment is best for treating a condition. To find out, we need to compare different treatments. We put people into groups and give each group a different treatment. The results are compared to see if one is better. To try to make sure the groups are the same, each participant is put into a group by chance (random).

QUARTET is a double-blind study. This means that neither you nor your study doctor will know which treatment you are receiving. However, in certain circumstances your study doctor can find out which treatment you are receiving.

In this study you will either receive the LDQT described above or receive a standard dose of a commonly prescribed medication for lowering blood pressure – Irbesartan 150mg.

Consent is absolutely essential in any clinical trial and will be the first thing to happen in the screening interview. Even if you do not want to participate in the Quartet trial we will require your consent to record any blood pressure measurements or data at our research centre.


Participation in the QUARTET study is for 12 weeks, divided into 3 study visits. If you wish to continue in the study to 12 months there will be 2 more visits at 26 and 52 weeks.

What to expect during Visit 1 (Screening & Baseline)
What to expect during Visit 2 (Week 6)
What to expect during Visit 3 (Week 12)
What to expect during Visit 4 (6 months)
What to expect during Visit 5 (12 months)
Does it cost anything to be involved in this study?
What if I am already taking medication?

Thank you for agreeing to be a part of our research study. Your contribution is invaluable and will directly improve the treatment options available for other people with cardiovascular issues.

Please visit our website for other clinical trials we are running and to hear more about the exciting achievements the Dobney Hypertension Centre is making. You can share this trial with others you think may benefit by sharing on your Facebook or Twitter page.


Project Members

Alice Rothwell
Quartet researcher

Research Assistant

Justine Chan
Local co-ordinator

Research Assistant / Registered Nurse

Professor Markus Schlaich
Principal Investigator

Nephrologist & Hypertension Specialist, MD, FAHA, FESC, NHMRC Senior Research Fellow