A $1.2 million nationwide project will evaluate how care for people with resistant high blood pressure can be improved in New Zealand. The project will comprehensively assess aspects of health delivery for people with high blood pressure.
A key part of the two year project will be a trial that will compare the effectiveness of a comprehensive clinical management approach with a new treatment that ‘zaps’ nerves to the kidney to reduce blood pressure.
The University of Auckland will lead this research, working with a large team of health professionals from across the country.
The trial will include several hundred people with resistant high blood pressure from throughout Auckland, Waikato and Christchurch.
The funding for the programme comes from the new Health Innovation Partnership that was established earlier this year between the National Health Committee and the Health Research Council of New Zealand.
The five district health boards in Auckland, Waikato and Christchurch are supporting the trial.
New Zealand Chair of the Cardiac Society of Australia and New Zealand Professor Ralph Stewart says renal denervation is a very promising technique, but its role in New Zealand health care is currently uncertain. Renal denervation is still new in this country and is only available in certain centres.
This trial will provide detailed, comprehensive advice for New Zealand on the optimal ways to help people with resistant high blood pressure. The trial itself, within this wider programme of work, will compare the effects of renal denervation to those of intensive medical management on blood pressure and other measures of health.
The trial will be clinically led, with strong participation from medical and interventional specialists and general practitioners.
Treating hypertension has been consistently shown to reduce the risk of cardiovascular disease and stroke, which are major health targets in New Zealand.
Background
Resistant high blood pressure is defined as having a systolic blood pressure greater or equal to 160mmHg despite taking at least three blood pressure lowering medications. Normal blood pressure is less than 120mmHg (systolic) and less than 80mmHg (diastolic).
The renal denervation procedure involves passing a tube from the groin artery to the renal artery and quietening the sympathetic nerves to the kidney by “zapping” them with radiofrequency energy.
People with resistant high blood pressure need quite intensive help to lower their blood pressure. Lifestyle changes, including reducing salt intake and losing weight, along with combinations of tablet treatment can help some people. For others, a simple catheter procedure that removes excess nerve signals to and from the kidneys called renal denervation can markedly reduce blood pressure.
High blood pressure or hypertension affects at least one in four New Zealand adults. Over many years this increases their risk of heart attack, stroke, heart failure, kidney disease, and death. Although the disease can be treated aggressively with lifestyle changes and prescription medication, for the estimated two to four per cent of people with resistant hypertension, these steps alone aren’t enough.
The University of Auckland-led trial follows the evaluation by the National Health Committee of four cardiac interventions. Documents will be released to the sector for feedback shortly.
The National Health Committee has worked closely with the Cardiac Society of Australia and New Zealand in reaching its decisions and will now be consulting more widely with interested sector groups before finalising its advice to the Government.