Objective: We examined the relationships between the National Institute of Health Stroke Scale (NIHSS) and physical, cognitive, and social participation outcomes across subpopulations of stroke survivors on the basis of cortical involvement and lesion lateralization.
Design: Families in Recovery from Stroke Trial participants were classified with respect to lesion lateralization (n = 274) and cortical involvement (n = 158). NIHSS scores (average 13 days after stroke) were used to predict Physical Performance Test times (PPT), limitations in activities of daily living (Augmented Barthel Index (ABI)), Instrumental Activities of Daily Living (IADL), cognitive function, depressive symptoms (Center for Epidemiologic Studies Depression scale [CES-D]), and productive, recreational, self-care, and social role activities 3 and 6 mos later. We compared the relationship between NIHSS and each outcome in stroke subgroups classified by lesion lateralization and cortical involvement.
Results: NIHSS predicted physical performance, activities of daily living, and IADL independence. The association between NIHSS and both PPT and IADLs was less steep for patients with cortical lesions than for patients with exclusively subcortical lesions. NIHSS predicted physical performance, activities of daily living, or IADLs similarly for right- and left-hemisphere strokes, but hemisphere modified the association between NIHSS and CES-D and cognitive measures.
Conclusions: The NIHSS may predict outcomes in subpopulations of stroke survivors with subcortical lesions better than in patients with cortical involvement. NIHSS predicted CES-D in patients with right-sided lesions but not in those with left-sided lesions. In contrast, NIHSS had little association with cognitive outcomes among patients without left-side involvement.