Objective: To determine the association between admission blood glucose and outcome in ischemic stroke patients treated with thrombolysis. Design: A prospective, open, multinational, observational study. Setting: An ongoing Internet-based, academic-driven, interactive thrombolysis register. Patients: Between 2002 and 2007, 16 049 patients were recorded in the SITS-ISTR. Main Outcome Measure: Blood glucose was recorded at admission. Blood glucose was divided into the following categories: less than 80,80-120 (reference range), 121-140, 141-160, 161-180, 181-200, and greater than 200 mg/dL. Outcomes were mortality and independence (modified Rankin Scale score of 0-2) at 3 months and symptomatic intracerebral hemorrhage (SICH) (Nat...