More Intensive Blood Pressure-Lowering Therapy May Reduce Recurrent Stroke Risk

The risk for recurrent stroke and major cardiovascular events is associated with the use of more intensive blood pressure-lowering therapy, according to the findings of a systematic review and meta-analysis published in JAMA Neurology.

Hypertension is a well-established risk factor for recurrent stroke and as such, blood pressure-lowering interventions are a guideline-recommended strategy to prevent recurrent stroke. Despite this recommendation, most clinical trials have not shown significant reductions in recurrent stroke with blood pressure-lowering therapy.

To obtain a better understanding of the relationship between recurrent stroke risk and blood pressure-lowering interventions, researchers from Chang Gung University College of Medicine in Taiwan searched publication databases through June 2022 for randomized clinical trials, using antihypertensive or blood pressure-lowering interventions among patients with a history of stroke.

This analysis included 10 trials comprising 40,710 patients with a history of stroke or transient ischemic attack (TIA). The patients were mean age 65 years; 34% were women; they had systolic blood pressure of 146 mmHg and diastolic blood pressure of 85 mmHg at baseline. The trials evaluated antihypertensive drugs compared with placebo or no intervention (n=6) or compared the effects of a lower blood pressure target with a higher blood pressure target (n=4).

More intensive blood pressure-lowering therapy associated with a significant reduction in recurrent stroke among patients with stroke or TIA (risk ratio [RR], 0.83; 95% CI, 0.78-0.88; I², 79%; P <.001).

A reduction in systolic blood pressure by 5 mmHg or greater associated with a RR of 0.90 and a 10-mmHg or greater reduction associated with an RR of 0.67 for recurrent stroke. Similarly, reducing diastolic blood pressure by 3 mmHg or greater (RR, 0.84) and 5 mmHg or greater (RR, 0.60) associated with lower recurrent stroke risk.

In addition, more intensive rather than less intensive blood pressure-lowering therapy associated with reduced risk for:

• hemorrhagic stroke (RR, 0.54; 95% CI, 0.43-0.68; I², 69%; P <.001),
• fatal or disabling stroke (RR, 0.76; 95% CI, 0.64-0.89; I², 0%; P <.001),
• death from cardiovascular causes (RR, 0.86; 95% CI, 0.78-0.96; I², 0%; P =.006),
• recurrent ischemic stroke (RR, 0.87; 95% CI, 0.81-0.94; I², 75%; P <.001), and
• major cardiovascular events (RR, 0.88; 95% CI, 0.83-0.92; I², 71%; P <.001) among patients with a history of stroke or TIA.

In subgroup analyses, significant interactions were observed for time of recruitment since stroke event (P <.001), the proportion of the study population that was Asian (P <.001), for trials using angiotensin-converting enzyme inhibitors plus diuretics compared with trials using monotherapies (P <.001), and the follow-up duration (P =.01).

This analysis may have been limited, as stroke incidence was not the outcome of interest in some studies, which may have led to the underreporting of events.

These data indicated that more intensive blood pressure-lowering interventions significantly reduced recurrent stroke risk among patients who had a history of stroke or TIA.

Researchers acknowledged that “These results might support the use of more intensive blood pressure reduction for secondary stroke prevention chronically.”

Disclosure: One study author declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.