The presence of microbleeds might increase the risk of ICH recurrence in warfarin users, although there are no prospective data. In a pooled analysis of ICH and ischemic stroke or transient isch- emic attack patients, microbleeds were more frequent in war- farin users with ICH than in nonwarfarin users (OR, 2.7; 95% CI, 1.6 4.4; P<0.001) but were not more frequent in warfarin users with ischemic stroke or transient ischemic attack (OR, OR, 0.01), and the presence of microbleeds was associated with a higher risk of subsequent ICH (OR, 12.1; 95% CI, 3.4 The optimal timing for resumption of anticoagulation after ICH, if necessary, is uncertain, and no randomized trial data are available to guide the decision. Several observational studies of patients with anticoagulant-related ICH found low rates of cardioembolic events while not receiving anti- coagulation therapy or recurrent ICH when anticoagulation but the results are limited by relatively small sample sizes and short durations of follow-up. A larger study of 234 patients with warfarin-related ICH followed up for a median of 34 weeks found that the risk of rebleeding with early resumption of anticoagulation exceeded the risk of thromboembolism from withholding it, whereas later, the opposite was true.294 A survival model based on these data found that the total risk of ischemic plus hemorrhagic stroke was minimized when anticoagulation was reinitiated after 10 weeks, and the authors suggested a delay of at least 1 month after ICH.294 In practice, the timing often depends on the indication for anticoagulation. In patients with pros- thetic heart valves, early resumption of anticoagulation may be necessary because of the high risk of embolism. 