According to research, “high-normal” blood pressure still poses risk of stroke. 
Normal blood pressure is between 120/80 mm Hg and 129/84 mm Hg, “Abnormal” blood pressure is a top number (systolic pressure) above 140 mm Hg, and a bottom number (diastolic pressure) above 90 mm Hg, said the Heart and Stroke Foundation.
Patient whose top number is between 120 and 139 mm Hg, or their bottom number is between 80 and 89 mm Hg, is in the condition of “prehypertension” or “high-normal.”, said the experts. But this new study suggests there’s nothing “normal” or safe about this range.
The study, in the journal Neurology, reported more than 518,000 adults from 12 previous studies that looked at blood pressure, are at the risk of stroke.
50 percent of people who are with prehypertension would likely to have a stroke compared with those with normal blood pressure index, even after the researchers took into account such factors such as age, diabetes, obesity, cholesterol and smoking.
If blood pressure readings just a little above normal — 120/80 to 129/ 85, it can cause those in this case to have a 22 per cent higher risk of having a stroke.
Those with blood pressure between 130/ 80 to 139/ 89 had an 80 per cent higher risk of having a stroke.
If someone doesn’t meet the definition of high blood pressure, they may not assure that they are safe from stroke, said Antoine Hakim of the Canadian Stroke Network.
“It is very clear that people whose blood pressure is in the range 120 to 139 are at high risk of stroke. So we can’t just sit back and say, ‘Maybe you are upset or anxious.’ We need to do something,” he tells CTV News.
“If your systolic is above 130, something must be done about it because you are going to damage your brain,” he adds.
High blood pressure is considered to be a serious condition that is the number one risk factor for stroke and is a major risk factor for heart disease. Over time, high blood pressure damages blood vessel walls, causing scarring that stimulates the build-up of fatty plaque. This plaque can gradually block arteries, leading to a heart attack or an ischemic stroke.
It also strains the heart and eventually weakens it. Very high blood pressure can cause blood vessels in the brain to burst, resulting in a hemorrhagic stroke.
Hakim’s advice is not to put people with pre-hypertension on medication, but to urge them to measure their blood pressure at least once a month and to make lifestyle changes if it stays above normal.
“That means cut down on salt, increase fruit intake, exercise more, don’t be a couch potato. If you are smoking, quit,” he said.
The Heart and Stroke Foundation also recommends limiting alcohol to no more than one to two drinks a day, to a weekly maximum of 14 drinks for men and 9 drinks for women; and to find healthy ways to manage stress.
Only when all else fails to bring those numbers down should medications be considered, Hakim said.