['There are few data regarding anemia and transfusion after subarachnoid hemorrhage (SAH). We addressed the hypothesis that higher hemoglobin (HGB) levels are associated with less death and disability after SAH.', 'Prospective registry with automated data retrieval.', 'Six hundred eleven patients enrolled in the Columbia University SAH Outcomes Project between August 1996 and June 2002.', 'Neurologic intensive care unit.', 'Patients were treated according to standard management protocols.', 'We electronically retrieved all HGB readings during the acute hospital stay for 611 consecutively admitted SAH patients. Outcomes were measured with the modified Rankin Scale at 14 days or discharge, and at 3 months. Patients who were independent (modified Rankin Scale, 0-3) at discharge or 14 days had higher mean (11.7 +/- 1.5 vs. 10.9 +/- 1.2, p < .001) and nadir (9.9 +/- 2.1 vs. 8.6 +/- 1.8, p < .001) HGB, and had higher HGB values every day in the hospital. There were similar results when patients were stratified by mortality. Higher HGB was associated with reduced risk of poor outcome (modified Rankin Scale, 4-6) at 14 days/discharge and 3 months after correcting for Hunt and Hess grade, age, history of diabetes, and cerebral infarction. Length of stay and HGB interacted such that lower HGB has a more pronounced effect with length of stay > 14 days.'] Is higher hemoglobin associated with improved outcome after subarachnoid hemorrhage?