Predictors of major neurological improvement after intravenous thrombolysis in acute ischemic stroke: A hospital-based study from south India

Background: Despite the increasing use of recombinant tissue plasminogen activator (rt-PA) in acute ischemic stroke, uncertainty persists about the short-and long-term outcome of the thrombolysed patients. Objective: To identify predictors of major neurological improvement at 24 h after intravenous rt-PA administration in patients of acute ischemic stroke and their relationship with outcome at 12 months. Materials and Methods: We analyzed the data of the patients with acute ischemic stroke treated as per the National Institute of Neurological Disorders and Stroke (NINDS) criteria with intravenous rt-PA between January 2000 and June 2009 at a tertiary care center in south India. Major neurological improvement was defined by an 8-point improvement in National Institute of Health Stroke Scale (NIHSS) score or an NIHSS score of 0 or 1 at 24 h. Good outcome was defined as a 12-month modified Rankin Scale (mRS) of 0 to 1. Results: Of the 72 patients with acute ischemic stroke treated with intravenous rt-PA, 23 (32%) patients had major neurological improvement at 24 h. Age < 60 years (OR 1.9, 95% CI 1.7 to3.2), admission glucose levels < 8 mmol/L (OR 3.87, 95% CI 1.9 to 9.2) and mild to moderate baseline stroke severity (NIHSS median score 10+ 6) were associated with major neurological improvement after adjusting for co variables. Major neurological improvement at 24 h was an independent predictor of good outcome (mRS <= 1) at 12 months (OR 13.9, 95% CI 6.84 to 40.2). Conclusions: Age < 60 years, glucose levels < 8 mmol/L and mild to moderate stroke severity (NIHSS median score 10 +/- 6) was associated with major neurological improvement after intravenous rt-PA. Major neurological improvement at 24 h after the administration of intravenous thrombolysis independently predicted good outcome at 12 months.