Prevention of recurrent strokes: Antiplatelet drug cilostazol effective and safer than aspirin

Study highlights:

-- The antiplatelet drug cilostazol was better than aspirin in preventing a recurrent stroke in a Japanese trial.

-- Compared to patients taking aspirin, patients taking the drug were less likely to have new ischemic stroke or develop bleeding requiring hospitalization.

-- Cilostazol is used to reduce leg pain associated with peripheral vascular disease in the United States.

The antiplatelet drug cilostazol — used in the United States to treat leg pain associated with peripheral vascular disease — was more effective and safer than aspirin at  preventing recurrent strokes in a Japanese trial presented as late-breaking science at the American Stroke Association's International Stroke Conference 2010.

"This study demonstrated for the first time that cilostazol significantly reduces the risk of recurrent ischemic [blood-clot caused] stroke and the incidence of serious cerebral hemorrhage, compared to aspirin," said Yukito Shinohara, M.D., lead author of the study and head of neurology at Tachikawa Hospital in Tokyo, Japan.

Antiplatelet drugs interfere with the blood's ability to clot.

In the randomized, double-blind study of nearly 2,700 stroke patients with non-cardioembolic ischemic stroke (stroke not caused by blood clots originating in the heart), those treated with cilostazol were 25.7 percent less likely to suffer a stroke than those who received aspirin.

Among the study's other findings:

• Strokes occurred in 82 of the 1,337 cilostazol-treated patients (two strokes were fatal), during 2,965.9 person-years.  The 1,335-patient aspirin group suffered 119 strokes, including three deaths, over 3,203.6 person-years.  Person-years is the total time all patients in a group received their assigned drug.
• A hemorrhagic stroke or hemorrhage that required hospitalization occurred in 23 patients taking cilostazol and 57 of those receiving aspirin — a significant difference.

"The primary implication of this trial is that the risk of recurrence of stroke in patients can be reduced without increasing the incidence of hemorrhage by oral administration of cilostazol," Shinohara said.  

Cilostazol is approved in the United States only for reducing intermittent claudication, pain caused by an inadequate flow of blood to the leg muscles that's common with peripheral vascular disease.  In Japan, the drug is recommended and widely used for preventing recurrence of ischemic stroke.

Shinohara and colleagues sought to determine whether cilostazol's preventive powers were in the same range as — or superior to — the effects of aspirin.

The researchers analyzed results from 2,681 ischemic stroke patients treated in 278 Japanese institutions between December 2003 and October 2006.  Patients were followed through 2008. All patients had suffered non-cardioembolic ischemic stroke within 26 weeks prior to enrollment and their symptoms had remained stable.  They were randomized to receive either 100 mg of cilostazol twice daily or 81 mg of aspirin once daily.

"During the trial, we noted that the incidence of recurrent stroke was very low," Shinohara said. "We did not expect that there would be differences between the recurrence rate of stroke in the cilostazol and aspirin groups."