Data from: NIHSS cut-point for predicting outcome in supra- vs infra-tentorial acute ischemic stroke

Objective: To determine the optimal cut-point on the National Institutes
of Health Stroke Scale (NIHSS) for predicting poor 90-day clinical outcome
in patients with supra- and infra-tentorial acute ischemic stroke (AIS).
Methods: Data are from participants of the alteplase-dose arm of the
randomised controlled trial, Enhanced Control of Hypertension and
Thrombolysis Stroke Study (ENCHANTED). Associations between baseline
characteristics of clinically-defined supratentorial and infratentorial
AIS patients and poor functional outcome, defined by scores 3-6 on the
modified Rankin scale (mRS), were evaluated in logistic regression models,
with area under curve (AUC) receiver operating characteristics defining
the optimal NIHSS predictor cut-point. Results: Patients with
infratentorial AIS (n=289) had lower baseline NIHSS scores than those with
supratentorial AIS (n=2613) (median 7 vs 9; p <0.001). NIHSS
cut-point for poor outcome were 10 (AUC 76, sensitivity 65%, specificity
73%) and 6 (AUC 69, sensitivity 72%, specificity 56%) in supratentorial
and infratentorial AIS, respectively. There was no significant difference
in functional outcome or symptomatic intracranial hemorrhage between AIS
types. Conclusions: In thrombolysis-eligible AIS patients, the NIHSS may
underestimate clinical severity for infratentorial compared to
supratentorial lesions for a similar prognosis for recovery. Because
thrombolysis treatment has low effect on stroke outcome in patients with
infratentorial AIS when baseline NIHSS score is more than 6, additional
treatment such as endovascular treatment should be considered to improve
stroke outcome. Trial Registration: The trial is registered with
ClinicalTrials.gov (NCT01422616).