Lower BP Immediately After Stroke May Not Prevent Death, Disability

Acute ischemic stroke patients on antihypertensives may not have a lower risk of death or disability

(RxWiki News) While managing blood pressure can lower the risk for stroke, the benefits may not be as great for patients who have already experienced a stroke.

A recent study found that among ischemic stroke patients who were give antihypertensive medications (medicine to lower high blood pressure) within the first 48 hours after the onset of an acute ischemic stroke, there was no significant decrease in chance of death or disability.

"Follow your doctor’s treatment plan after a stroke."

This study was led by Jiang He, MD, PhD, from the Department of Epidemiology at Tulane University School of Public Health and Tropical Medicine in Louisiana. The research team examined the effects of blood pressure reduction on the likelihood of death in acute ischemic stroke patients.

Ischemic stroke occurs when there is blockage of a blood vessel that supplies blood to the brain.

For this study, the researchers analyzed data from 4,071 acute ischemic stroke patients who were 22 years of age or older in the China Antihypertensive Trial in Acute Ischemic Stroke (CATIS). Patients were selected from 26 hospitals across China and split into two groups.

The first group included 2,038 patients who received antihypertensive medication within the first 24 hours after having a stroke to help lower their blood pressure to less than 140/90 mmHg. The second group included 2,033 patients who were told to stop using any antihypertensive medications they were taking.

The researchers recorded if any study participants died within 14 days after being on the antihypertensive medication or if they experienced major disability. Major disability was measured using the modified Rankin Scale, which is used to measure recovery for stroke patients. Total possible scores ranged from 0 to 6, with a score of 0 indicating that there were no symptoms present, a score of 5 indicating major disability, and a score of 6 indicating death. Major disability included things like being bedridden, an inability to urinate or requiring constant medical care and attention.

Several factors were taken into account that could have influenced a patient’s likelihood of dying or experiencing major disability including: age, sex, blood pressure, smoking status, alcohol consumption, presence of other conditions (e.g., diabetes and coronary heart disease), history of hypertension and history of antihypertensive medication use.

The researchers found that after 14 days of taking medication, the average systolic blood pressure (measure of blood pressure when the heart beats) was reduced from 166.7 mmHg to 135.2 mmHg in the antihypertensive treatment group.

The average systolic blood pressure fell from 165.6 mmHg to 152.9 mmHg in the no treatment group after 14 days.

There was no significant difference found between the groups in terms of the percentage of patients who died or experienced major disability at 14 days after the study began. In both groups, 33.6 percent of patients died or experienced major disability.

The authors did note that their study had some limitations. Patients with a blood pressure of 220/120 mmHg or greater were excluded from the study. As a result, the findings cannot be applied to those patients. Additionally, the researchers did not run neurological tests that could have identified patients who would have benefited more from reducing their blood pressure.

The authors concluded that for patients who have experienced an ischemic stroke, reducing their blood pressure did not reduce their chance of death or major disability.

This study was published on November 17 in the Journal of the American Medical Association (JAMA).

The authors reported no competing interests. 

Review Date: 
November 18, 2013