Stroke survivors with uncontrolled high blood pressure who added an inexpensive diuretic medication called spironolactone to their treatment had lower blood pressure and reached the recommended blood pressure goal nearly twice as often as peers receiving usual post-stroke care, according to preliminary late-breaking science presented at the American Heart Association’s Scientific Sessions 2026 in Chicago.
The findings matter because High blood pressure is a leading, controllable risk factor for a second stroke. Nearly 1 in 4 stroke survivors will have another stroke, and up to 80% of strokes can be prevented, according to the 2021 American Heart Association/American Stroke Association Guideline for the Prevention of Stroke in Patients With Stroke and Transient Ischemic Attack. Recurrent strokes raise the risk of severe disability and poorer quality of life.
In the REDUCE trial, 160 adult stroke survivors with uncontrolled high blood pressure were randomized to daily spironolactone plus usual care or to usual care alone. At three months, home-measured systolic blood pressure averaged about 126 mm Hg in the spironolactone group versus 133 mm Hg in the standard care group—a difference of nearly 8 mm Hg. Diastolic pressure dropped by about 4 mm Hg more. By three months, 52% of people taking the diuretic had reached the recommended goal of less than 130/80 mm Hg, compared with 30% receiving standard care. At six months, systolic pressure remained about 7 mm Hg lower.
“Lowering blood pressure is the most important step in preventing another stroke, yet many survivors struggle to reach recommended blood pressure targets after a stroke,” said co-lead author Jordana B. Cohen, M.D., M.S.C.E., FAHA, an associate professor of medicine and epidemiology at the Perelman School of Medicine at the University of Pennsylvania. “When spironolactone was added to post-stroke care, we saw a meaningful drop in blood pressure that may lower the risk of future strokes and heart attacks.”
Spironolactone is a long-available, FDA-approved diuretic that blocks aldosterone, a hormone that signals the kidneys to retain salt and water. It is typically the fourth recommended medication for high blood pressure. The trial enrolled patients after ischemic stroke or intracerebral hemorrhage. The medication was well tolerated: serious side effects requiring hospitalization occurred in 15% of the spironolactone group and 16% of the standard care group, and high potassium levels occurred in about 4% of participants without life-threatening issues.
In an exploratory analysis, blood pressure fell more among people who started spironolactone within three months of their stroke. “We were surprised to see that blood pressure dropped twice as much as we expected,” Cohen said. The authors noted limitations: the trial compared spironolactone with usual care rather than another blood pressure medication, enrollment ended early at 160 of a planned 200 participants, and the study was not designed to determine whether spironolactone lowers the risk of another stroke or heart attack.
The results, considered preliminary until published in a peer-reviewed journal, could influence post-stroke prescribing and reinforce the value of home monitoring. The American Heart Association offers guidance on Preventing Another Stroke and runs the Target: BP initiative to improve blood pressure control. The study was funded by a Bugher Center grant from the American Heart Association.
