Background: Although the NIHSS is a well-validated tool in assessing neurological deficit and predicting long-term outcome in acute cerebral ischemia, its utility in ICH has not been extensively studied. As NIHSS is routinely obtained in cases of stroke prior to imaging, it is often available in ICH patients to potentially assist physicians in triage, prognostication, and risk-adjustment.
Methods: We analyzed consecutive patients enrolled in the NIH Field Administration of Stroke Therapy-Magnesium (FAST-MAG) phase 3 trial whose final diagnosis was ICH. Trained study nurses performed the NIHSS in the Emergency Department (ED) shortly after arrival and the modified Rankin Scale (mRS) at 90 days. Primary outcomes were disability or death (mRS 3-6) and mortality. Candidate potential predictor variables, including NIHSS, ICH Score, and GCS, those with threshold of p<0.10 were candidate parameters for backward selection logistic regression to determine independent predictors of disability or death and of mortality.
Results: Among the 384 ICH patients, age was mean 65 (±13); female 34%; race white 78%, black 10%, Asian 10%; Hispanic ethnicity 33%; and history of hypertension 78%. The ED NIHSS and GCS was performed a median 148 minutes (IQR 121-180) after last known well. Initial NIHSS was median 16 (IQR 9-16), GCS 15 (IQR 10-15), and ICH Score 1(IQR 0-2). NIHSS correlated with ICH Score (r=0.780) and GCS (r=0.860). At 90 days, median mRS was 4 (IQR 2-6), disability or death (mRS 3-6) was present in 70%, and mortality occurred in 26%. In predicting disability or death at 90 days, c statistics were: NIHSS 0.81, ICH Score 0.81, and GCS 0.72. NIHSS≥14 showed 72% sensitivity and 75% specificity. For mortality by 90 days, c statistics were: NIHSS 0.78, ICH Score 0.80, and GCS 0.73. NIHSS≥19 had 80% sensitivity and 70% specificity. On multivariate analysis age (OR 1.07, 95%CI 1.04-2.0) and NIHSS (OR 1.18, 95%CI 1.13-1.23) were independent predictors of disability and death.
Conclusions: The initial NIHSS is a strong predictor of disability and death and good predictor of mortality after intracerebral hemorrhage, performing as well as the ICH Score and better than the GCS. Consideration should be given to routine performance and documentation of the NIHSS in ICH patients.