Two new studies - from the USA and Australia - have indicated that tighter control of high blood pressure could help decrease the incidence of stroke, heart attack and kidney disease, potentially benefitting millions of New Zealanders.
For decades, we’ve been told anything below 140 over 90 is Normal Blood Pressure and anything above 140 is High. This means a systolic pressure of 140 milimetres of mercury (mm Hg) and a diastolic pressure of 90 milimetres of mercury. That’s all about to change with High Blood Pressure soon to be measured at 120 mm Hg.
Landmark research from the United States
The Systolic Blood Pressure Intervention (SPRINT) trial, published in the New England Journal of Medicine (NEJM), enrolled more than 9,000 people with blood pressure levels above 130 mm Hg who were at high risk of heart disease and stroke. It compared the effects of keeping levels below the currently recommended 140 mm Hg, to a much more intensive goal of 120 mm Hg or less.
Executive Director for The George Institute for Global Health Australia, Professor Vlado Perkovic was asked to write the editorial for this research, and said the research changes everything when it comes to understanding and treating high blood pressure.
“What this new research shows is that if we get blood pressure down to 120... we can reduce not only the risk of heart attack and stroke and heart failure, but we can prevent deaths.”
“High blood pressure is the number one cause of death and disability around the world," said Professor Perkovic. "This research found that keeping blood pressure levels below 120 mm Hg in a much broader range of people - including many not previously treated - prevents death and cardiovascular events."
Australian study supported by research
The SPRINT trial supports additional research published in the Lancet last week by The George Institute, which showed heart attacks and stroke can be prevented with more intensive management of blood pressure.
Principal Director, Professor Stephen MacMahon, said the study found intensive management gave patients greater protection than the current process. “Previously guidelines recommended lowering blood pressure to 140 mm Hg, but we found that going beyond this had great benefits for patients,” Prof MacMahon said.
“This confirms a quarter of a century of our research, which has argued that the guideline-recommended goal of 140 mm Hg is too high. We can reduce heart disease significantly and even save lives through intensive blood pressure lowering.”
So what does this mean for you and me?
We asked Professor Paul Pilowksy, High Blood Pressure Group Leader here at the Heart Research Institute to break it down for us.
“The results of this trial reinforce the importance of having blood pressure tested on a regular basis, particularly as you reach middle age. It’s also important to have your blood pressure tested if you’re a woman on the oral contraceptive pill or any other medication that is known to affect blood pressure, if you’re a person who suffers from snoring, if you are known to have sleep apnoea or a family history of any sort of cardiovascular disease or high blood pressure.”
“These sort of issues are well known to family practitioners who will be well aware of the best way to manage your personal situation. The findings of these studies, although important, are no cause for alarm for the average person.”
How does high blood pressure affect the body?
“Severely elevated blood pressure, in excess of 140 on 90, over a very prolonged period can be damaging to the arteries in the body, and if the arteries become damaged over long period, this can lead to what is known as target organ damage. Target organs include the heart, the brain and the kidneys,” says Paul.
"By bringing arterial blood pressure down to a level that is considered safe according to current guidelines, you will be at less risk of suffering from cardiovascular-related disorders such as heart attack, kidney disease or a stroke."
How do we reduce blood pressure?
There are many things that can be done for people diagnosed as having persistently elevated arterial blood pressure. Your doctor might advise you to lose weight, exercise, change your eating habits, or some combination of the above.
"Clearly, these kind of changes to lifestyle can be very challenging and for many people may not be possible," says Paul. "In these circumstances there may be no other option than to commence medication aimed at reducing blood pressure, particularly if the level of blood pressure is extremely high, or if there is a strong family history of high blood pressure or other cardiovascular risk factors.”
He adds: “It is important that individuals are not made to feel ashamed because they have high blood pressure. It is not a matter of blame or fault. As with many other diseases, such as kidney failure, juvenile onset diabetes or cancer, blood pressure elevation is commonly genetic and needs to be managed in the same way as any other disorder.