Validation of the National Institutes of Health Stroke Scale in Intracerebral Hemorrhage

BACKGROUND: We sought to determine if the National Institutes of Health Stroke Scale (NIHSS) has a greater discriminative power than Glasgow coma scale (GCS) to identify patients at risk of poor early functional outcomes and large hematoma volumes. METHODS: We prospectively collected clinical assessments, imaging, and outcome data in consecutive patients with intracerebral hemorrhage, and determined the ability of GCS and NIHSS to predict poor functional outcome (modified Rankin scale 3-6) and hematoma volume >30 cm(3) using receiver operating characteristics analysis, C-statistics, and the DeLong test. RESULTS: We studied 672 patients with intracerebral hemorrhage (mean age 62 +/- 14 years; 56% men; median intracerebral hemorrhage score=1, interquartile range (IQR) 0-2; median intracerebral hemorrhage volume 7 cm(3), IQR 2-19) with median NIHSS of 8 (IQR 3-18) and GCS 15 (IQR 7-15). NIHSS correlated strongly to GCS (r=-0.773; P<0.001). Admission NIHSS (C-statistic: 0.91; 95% CI, 0.89-0.93) predicted better than GCS (0.78; 95% CI, 0.75-0.81) discharge poor functional outcome (DeLong test P<0.001). NIHSS (0.82; 95% CI, 0.78-0.86) also discriminated better than GCS (0.78; 95% CI, 0.73-0.83) patients with large hematoma volume (DeLong test P=0.029). CONCLUSION: The NIHSS has a greater discriminative power than GCS to identify patients at risk of poor early functional outcomes and large hematoma volumes.