Dramatic Early Improvement in the NINDS Trial: Better 90 Day Outcomes and No Increased Rates of Intracranial Hemorrhage

Summary

This article discusses the results of a retrospective study that used data from the rt-PA arm of the National Institute of Neurological Disorders (NINDS) trial [Kwiatkowski TG et al. N Engl J Med 1999] to evaluate dramatic early improvement after treatment with IV-rt-PA as a risk factor for the development of posttreatment ICH. A secondary objective was to characterize the subgroup of patients with dramatic early improvement.

  • Ischemia Clinical Trials

NIHSS baseline score and time to treatment <90 minutes are independent predictors of dramatic early response to rt-PA therapy. The occurrence of intracerebral hemorrhage (ICH) is similar between dramatic and nondramatic responders.

Clinical experience demonstrates that a certain percentage of patients with acute ischemic stroke improve rapidly after the administration of IV-rtPA [Felberg RA et al. Stroke 2002]. Although research in a small number of patients has pointed to the development of subtypes of mild hemorrhage as a marker for early recanalization and good clinical outcomes at 90 days (OR, 10.9) [Molina CA et al. Stroke 2002], anecdotal clinical experience has suggested a potential relationship between dramatic early improvement and posttreatment symptomatic ICH.

Jordan Bonomo, MD, University of Cincinnati, Cincinnati, OH, reported on the results of a retrospective study that used data from the rt-PA arm of the National Institute of Neurological Disorders (NINDS) trial [Kwiatkowski TG et al. New Engl J Med 1999] to evaluate dramatic early improvement after treatment with IV-rt-PA as a risk factor for the development of posttreatment ICH. A secondary objective was to characterize the subgroup of patients with dramatic early improvement.

Demographics, baseline clinical characteristics, rates of ICH, and outcomes were compared between subjects with and without dramatic improvement. Dramatic improvement was defined as either NIHSS ≤2 at 2 hours or a 10-point improvement from baseline at 2 hours after initiation of therapy [Alexandrov et al. Stroke 2000]. Logistic regression was used to predict posttreatment ICH, as well as good clinical outcome at 90 days (mRS 0–1).

Of the 312 patients who were treated with IV-rt-PA, 65 (20.8%) had dramatic early improvement and 246 (78.8%) did not. Early dramatic improvement was strongly associated with good clinical outcome at 90 days (78% dramatic responders vs 33% of nondramatic responders; p<0.0001). NIHSS baseline score and time to rt-PA therapy <90 minutes were the only independent predictors of early dramatic improvement. The occurrence of ICH by 36 hours (both symptomatic and asymptomatic) was not significantly different (p=0.27) between the dramatic (4/65; 6.2%) and nondramatic improvement (29/246; 11.8%) groups. After adjustment for dramatic improvement, age, and CT edema, only CT mass effect and baseline NIHSS were predictive of symptomatic ICH in dramatic improvers. Age, baseline NIHSS, and dramatic improvement were independent predictors of good outcome at 90 days (Table 1).

Table 1.

Predictors of Rapid Response, sICH in Rapid Responders, and Outcome.

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