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Blood pressure–lowering drugs reduce strokes and deaths in people with mild high blood pressure and no cardiovascular disease
Sundstrom J, Arima H, Jackson R, et al. Effects of Blood Pressure Reduction in Mild Hypertension: A Systematic Review and Meta-analysis. Ann Intern Med. 2015;162:184-91.
In people who have mild high blood pressure (BP), but not cardiovascular (CV) disease, do drugs used to lower BP reduce CV events (e.g., stroke, heart attack, coronary heart disease)?
High BP is usually defined as having a systolic BP of 140 mm Hg or more or a diastolic BP of 90 mm Hg or more. Mild high BP is defined as having a systolic BP of 140 to 159 mm Hg or a diastolic BP of 90 to 99 mm Hg. High BP often doesn’t cause symptoms but, over time, can cause strokes or heart problems, including heart attacks.
Drugs used to lower high BP can reduce risk of CV events, although they may work differently in people with mild high BP.
How the review was done
The researchers included data from randomized controlled trials published up to June 2014. The trials included 15,266 people with mild high BP.
The key features of the trials were:
- people were 18 years of age or older and initially did not have CV disease (e.g., previous stroke, angina, heart attack, heart surgery or other heart procedures, kidney failure [where kidneys can no longer get rid of waste and fluid from the blood], or peripheral artery disease [blockages or narrowing in the blood vessels in the legs and arms]);
- drugs were given to lower BP;
- most drugs were compared with placebo, although some trials compared more-intensive with less-intensive drug regimens; and
- people were treated for 4 to 5 years.
What the researchers found
Compared with control (placebo or less-intensive drug regimens), drugs used to lower BP:
- reduced strokes and deaths; and
- had similar rates of coronary events (heart attack or death caused by coronary heart disease) or heart failure (problems with the heart’s ability to pump blood).
Blood pressure–lowering drugs reduce strokes and deaths in people who have mild high blood pressure and no cardiovascular disease.
Blood pressure (BP)-lowering drugs vs control* in people with mild high BP and no cardiovascular (CV) disease
Major CV events†
9 trials (12,970 people)
9 trials (12,411 people)
About 6 fewer people out of 1000 had a stroke
8 trials (12,925 people)
6 trials (5,629 people)
Death caused by CV events
6 trials (5,881 people)
About 11 fewer people out of 1000 died because of a CV event
Death by any cause
10 trials (15,239 people)
About 10 fewer people out of 1000 died
Chest pain due to reduced blood flow to the heart.
Adverse events caused by conditions affecting the coronary arteries that supply oxygen and blood to the heart.
Coronary heart disease
Also known as coronary artery disease (CAD), is a narrowing of the blood vessels (coronary arteries) that supply oxygen and blood to the heart.
The lower number in a blood pressure reading. It is the pressure when the heart rests between beats.
A harmless, inactive, and simulated treatment.
Randomized controlled trials
Studies where people are assigned to one of the treatments purely by chance.
The higher number in a blood pressure reading. It is the pressure in the arteries when the heart beats.
The body's network of blood vessels. It includes the arteries, veins, and capillaries that carry blood to and from the heart.
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Health Link B.C.
The Canadian Hypertension Education Program recommends that all adults get their blood pressure tested when they visit the doctor. If you are at risk for heart disease or a disease caused by high blood pressure, you should get your blood pressure checked more often.
Eating too much salt can make existing high blood pressure and heart disease worse. More unbiased and high quality research is needed to know whether salt intake is really a risk for healthy adults.
Harvard School of Public Health
Eating too much salt can increase your blood pressure and lead to heart disease, especially if you are over 50, have high blood pressure or diabetes, or are African American. Try to eat less than a teaspoon of salt a day.
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