Key messages
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In adults who had treatment to reopen a blocked brain artery, lowering blood pressure very intensively (usually below 160 mmHg) does not improve the chances of living independently three months after the stroke compared with standard blood pressure targets (usually below about 180 mmHg). “Living independently” means being able to walk and manage most everyday activities without help.
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Intensive blood pressure lowering probably increases the risk of death and poor recovery after stroke. Differences in brain bleeding between intensive and standard blood pressure strategies were small.
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Most of the people in the studies were treated in hospitals in upper-middle and high-income countries with specialized stroke services. We do not know whether the results would be the same in countries with fewer resources or in all groups of people who have an ischemic (blood blockage) stroke.
What is an ischemic stroke?
A stroke occurs when the blood supply to part of the brain is suddenly interrupted. In an ischemic stroke, this interruption is caused by a blood clot blocking an artery in the brain. It can lead to various neurological problems, such as weakness, decreased sensitivity, lack of coordination, and difficulty speaking.
How is a stroke treated?
Doctors can sometimes reopen the blocked artery using clot-busting medicines given into a vein, or by performing a procedure to remove the clot with a thin tube passing through the blood vessels (often called mechanical thrombectomy). These are called reperfusion treatments because they restore blood flow to the brain.
After reperfusion, many people have very high blood pressure, which can increase the risk of bleeding in the brain. However, lowering blood pressure too much or too quickly can reduce blood flow to brain tissue that is still at risk and be harmful to the brain.
What did we want to find out?
We wanted to find out whether intensive blood pressure lowering after reperfusion treatment, compared with standard blood pressure control:
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improves recovery and ability to live independently;
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improves health-related quality of life;
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improves survival;
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increases or reduces bleeding in the brain;
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decreases the duration of days in hospital;
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affects the frequency of other unwanted effects.
What did we do?
We searched for clinical studies (in which people are assigned to groups by chance) that included adults with ischemic stroke who had received reperfusion treatment with a clot-busting medicine, mechanical thrombectomy, or both, and compared more intensive blood pressure targets (less than 160 mmHg) with standard targets (less than 180 mmHg) shortly after reperfusion.
We combined and summarized the results of the studies. We also considered how the studies were conducted, the number of participants included, and the similarities and differences between the studies to judge how much confidence we can have in the results.
What did we find?
We found nine studies, involving 4381 adults with ischemic stroke who had reperfusion treatment. Most participants were treated in hospitals in high-income countries, with a smaller number in hospitals in middle-income countries. None of the studies took place in low-income countries. In most studies, the intensive strategy aimed to keep systolic blood pressure (the top number in a blood pressure reading) below 140 mmHg, while the standard strategy aimed to keep it below about 180 mmHg.
Main results
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Intensive blood pressure lowering makes little or no difference to the chance of living independently about three months after the stroke, compared with standard blood pressure control.
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Intensive blood pressure lowering probably makes little or no difference to health-related quality of life.
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Differences in brain bleeding (including severe bleeding that worsens symptoms) between intensive and standard blood pressure strategies were small and uncertain.
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Intensive blood pressure lowering probably increases the risk of death and probably increases the chance of a poor recovery after stroke.
Overall, the results suggest that lowering blood pressure to very low levels after reperfusion is unlikely to provide additional benefit and might cause harm in some people, compared with keeping blood pressure within more standard targets.
What are the limitations of the evidence?
The evidence has several important limitations, such as the relatively small numbers of people in some studies, which reduce the reliability of the results. Additionally, most participants were treated in specialized centers in middle and high-income countries; there is no evidence from low-income countries. Some groups of people may be under-represented (for example, older adults with many other health problems), and many studies did not provide detailed results separately for women and men.
Because of these limitations, the results should be interpreted with caution. More research is needed to determine whether specific groups of people might benefit from different blood pressure targets.
How up to date is this evidence?
The evidence in this review is up to date as of March 2025.
Read the full abstract
Objectives
To assess the benefits and harms of intensive systolic blood pressure management (target less than 160 mmHg) versus conventional management (target less than 180 mmHg) in people undergoing ischemic stroke reperfusion via systemic thrombolysis or endovascular thrombectomy.
Search strategy
We searched CENTRAL, MEDLINE, Embase, and two trial registers, together with reference checking, citation searching, and contact with study authors, to identify studies. The latest search date was 20 March 2025.
Authors' conclusions
Intensive systolic blood pressure management likely results in little to no clinically meaningful differences in quality of life, clinical function (continuous outcome), neurologic status (continuous outcome; NIHSS), or hospital length of stay. It also results in little to no clinically meaningful difference in clinical function (dichotomous) and does not increase or reduce neurologic adverse events. Additionally, it may result in little to no clinically meaningful difference in symptomatic neurologic adverse events and other adverse events. Lastly, it probably reduces the number of participants with a favorable neurologic status (dichotomous outcome) and probably increases all-cause mortality. The certainty of the evidence ranged from very low to high.
New studies must identify which patients benefit from different blood pressure strategies through subgroup analyses based on age, baseline blood pressure, and stroke severity, while reporting sex-disaggregated data. Including imaging and physiological markers can help set individualized blood pressure targets. Future trials should involve participants from low- and middle-income countries and consider factors such as access to reperfusion therapy and drug availability.
Funding
This Cochrane review had no dedicated funding.
Registration
Protocol (2025) available via doi.org/10.1002/14651858.CD016085.
