In people using blood pressure–lowering drugs, more-intensive therapy reduces cardiovascular events and strokes more than less-intensive therapy

Xie X, Atkins E, Lv J, et al. Effects of intensive blood pressure lowering on cardiovascular and renal outcomes: updated systematic review and meta-analysis. Lancet. 2016;387:435-43.

Review question

In people who are prescribed drugs to lower blood pressure, does more-intensive therapy reduce the risk for major cardiovascular events (e.g., heart attack, heart failure) and stroke compared with less-intensive therapy?

Background

People with high blood pressure and some other conditions (e.g., diabetes, kidney disease) are more likely than many other people to have a major cardiovascular event. High blood pressure is usually defined as having a systolic blood pressure (SBP) of 140 mm Hg or more or a diastolic blood pressure (DBP) of 90 mm Hg or more.

Drugs that lower blood pressure can reduce risk for cardiovascular events. More-intensive drug therapy can reduce blood pressure more than less-intensive drug therapy. It may also be better for reducing cardiovascular events but could have more side effects.

How the review was done

The researchers did a systematic review, searching for studies that were published up to November 2015.

They found 18 randomized controlled trials with 44,604 adults (average age 41 to 77 years, 37% to 74% men) and 1 randomized controlled trial with 385 children (average age 12 years, 59% boys).

The key features of the studies were:

• most people had high blood pressure; some had diabetes, chronic kidney disease, or more than one condition that increased risk for cardiovascular events;
• drugs were used to reduce blood pressure to specific levels or by specific amounts;
• more-intensive therapy was compared with less-intensive therapy;
• more-intensive therapy aimed to reduce blood pressure more than less-intensive therapy; and
• people were followed up for at least 6 months (3.8 years on average).

What the researchers found

Compared with less-intensive therapy, more-intensive blood pressure–lowering therapy:

• reduced blood pressure (SBP by 6.8 mm Hg and DBP by 3.5 mm Hg);
• reduced major cardiovascular events and stroke;
• had similar rates of death, heart attack, heart failure, and end-stage kidney disease; and
• had higher rates of severe low blood pressure, which can cause dizziness or fainting, although yearly event rates were low in both groups (0.1% in the lower-intensity group vs 0.3% in the higher-intensity group, with adverse events leading to discontinuation of treatment in 1% for each group).

Conclusion

In people who are prescribed drugs to lower blood pressure, more-intensive therapy reduces cardiovascular events and strokes more than less-intensive therapy.

More- vs less-intensive blood pressure–lowering therapy*

CV = cardiovascular.

*More-intensive drug therapy aimed to reduce blood pressure more than less-intensive drug therapy.

†This includes heart attack, heart failure, stroke, or death because of a CV event.

‡Although the rates for the 2 groups look a little different, the differences were not statistically significant. This means that the differences could simply be due to chance rather than due to the different treatments.

§End-stage kidney disease occurs when damage to kidneys is severe and cannot be reversed, usually requiring dialysis or kidney transplant.