La Trobe University and the Baker Heart and Diabetes Institute are leading a major new study into the causes of high blood pressure and have found a possible link with chronic inflammation.
The findings, published in the journal Cardiovascular Research, could pave the way for new treatments for high blood pressure, using inflammation-suppressing drugs usually reserved for patients with autoimmune diseases such as rheumatoid arthritis.
High blood pressure – or hypertension – is the world's number one risk factor for disease, affecting 1.13 billion people worldwide* ** - often leading to heart attacks and stroke. However, very little is known about its causes.
Professor Grant Drummond, co-director of La Trobe's Research Centre for Cardiovascular Biology and Disease - who is leading the research with collaborators from La Trobe University, the Baker Institute, the Hudson Institute and the University of Bonn in Germany - said it was vital to first identify the root cause of high blood pressure, before more effective treatments can be found.
"Up to 20 per cent of patients with high blood pressure fail to have their condition controlled by current therapies which include diuretics, blood vessel dilating agents and drugs that reduce heart rate," Professor Drummond said.
"These patients are then more likely to suffer debilitating or fatal heart attacks and strokes."
The research team is exploring the possibility that high blood pressure is caused by chronic inflammation.
Dr Antony Vinh, one of the other lead scientists from La Trobe said the team is testing the idea that lifestyle factors such as high salt and high fat diets directly activate an enzyme found in the kidneys and blood vessels – known as the inflammasome.
"Once activated, this enzyme produces chemical signals that attract immune cells, setting up an inflammatory response that disrupts the blood pressure-regulating functions of the kidneys and blood vessels," Dr Vinh said.
"This process is normally used to protect us from bacteria and viruses, but occasionally immune cells get confused and mount a response to relatively harmless substances.
"In the case of hypertension, the 'harmless' substances that appear to be at the centre of the problem are glass-like shards of crystalline salt, cholesterol and uric acid that build up in the blood vessels and kidneys."
Professor Drummond explained that by suppressing the activity of the inflammasome and reducing inflammation it may be possible to prevent blood vessel and kidney damage and reduce blood pressure in patients with hypertension.
"Inflammation-suppressing drugs are already used for the treatment of autoimmune diseases such as rheumatoid arthritis and gout and we have shown that similar drugs can be used just as effectively to reduce blood pressure in mice with hypertension.
"These findings could pave the way for new treatment approaches, where drugs currently reserved for patients with autoimmune diseases are repurposed for the treatment of high blood pressure," Professor Drummond said.
"Ultimately this could help save millions of lives and significantly reduce the global burden of disease resulting from high blood pressure."
The research is funded by the National Health and Medical Research Council of Australia (NHMRC) and was published in November in the prestigious international journal Cardiovascular Research.
Link to paper here.
*WHO
***The 2017 annual Global Burden of Disease (GBD) study published on 9 November 2018, placed high blood pressure as the world's number one risk factor for disability-adjusted life years. In 1990 it ranked fifth in the world.
