A simple clinical and MRI scale to predict good outcome in t-PA patients

The frequency of good outcome at 3 months after tissue plasminogen activator (t-PA) therapy is ∼35%. The present study aimed to devise a simple scale to predict good outcome using clinical factors and magnetic resonance imaging (MRI) findings before and immediately after t-PA infusion.

Consecutive patients with acute ischemic stroke treated with t-PA within 3 hours of stroke onset were studied prospectively. We assessed clinical factors independently associated with good outcome [modified Rankin scale (mRS): 0-1] at 3 months after t-PA therapy. We created a simple scale to predict good outcome in t-PA patients using factors selected by multivariate logistic regression analysis.

Subjects comprised 105 patients (69 men; median age, 74 years). Multivariate logistic regression analysis revealed the following independent factors associated with good outcome: baseline National Institutes of Health Stroke Scale (NIHSS) <11 [odds ratio (OR), 13·64; 95% confidence interval (CI), 3·588-51·822; P = 0·0001], glucose <150 mg/dl (OR, 3·76; 95%CI, 1·014-13·963; P = 0·0475), and early recanalization within 1 hour after t-PA infusion (OR, 5·28; 95%CI, 1·179-23·656; P = 0·0296). Those three variables were selected for use in the good outcome scale, with NIHSS <11 as 2 points, glucose <150 mg/dl as 1 point, and early recanalization as 1 point. Frequencies of patients with good outcome for each score were as follows: score 0, 0·0%; score 1, 7·1%; score 2, 43·5%; score 3, 65·4%; and score 4, 71·4%. The C statistic for the score was 0·849 (95%CI, 0·776-0·922).

A simple clinical and MRI scale can predict good outcome in t-PA patients.