SAN FRANCISCO — As many as 26,500 ischemic strokes occurring in the United States each year may be associated with patient withdrawal from antithrombotic and antiplatelet medications, according to a study presented at the International Stroke Conference.
Among 2,082 patients in the Cincinnati area who had 2,191 ischemic strokes in 2005, 84 (3.8%) of the strokes occurred in patients who had stopped their medications within 60 days. The first 7 days after withdrawal of antiplatelet or antithrombotic medication appeared to be the most dangerous time, Dr. Jordan Bonomo of the University of Cincinnati reported.
A total of 182 strokes occurred in warfarin patients. Of the 58 strokes that occurred in those who went off warfarin, 31 were within 7 days of withdrawal, 12 at 8–14 days, 8 at 15–30 days, and 7 at 31–60 days.
Similarly, 896 patients had been taking aspirin around the time of their stroke. Of these, 44 had discontinued aspirin; 24 of the strokes occurred within 7 days after halting aspirin therapy, 7 at 8–14 days, 11 at 15–30 days, and 2 at 31–60 days.
The investigators found a similar pattern among 228 patients who had been taking clopidogrel around the time of their stroke, 21 of whom had stopped taking the drug—10 strokes occurred within 7 days of discontinuation, 4 at 8–14 days, 5 at 15–30 days, and 2 at 31–60 days.
These results “mandate continued review of guidelines for withdrawal of anticoagulant and antiplatelet medication in the peri-procedural period,” he said.
Dr. Bonomo stated that he had no conflicts of interest. The study was supported by the National Institute of Neurological Disorders and Stroke.