Lesion characteristics, NIH stroke scale, and functional recovery after stroke

Area of Science:

• Neurology
• Rehabilitation Medicine
• Clinical Neuroscience

Background:

• The National Institute of Health Stroke Scale (NIHSS) is a crucial tool for assessing stroke severity.
• Understanding how NIHSS scores relate to long-term recovery is vital for personalized rehabilitation strategies.
• Subpopulations of stroke survivors may exhibit differential responses to the NIHSS predictive capabilities.

Purpose of the Study:

• To investigate the relationship between NIHSS scores and various functional outcomes (physical, cognitive, social participation).
• To examine these relationships across stroke survivor subpopulations defined by cortical involvement and lesion lateralization.
• To determine if NIHSS predictive accuracy varies based on lesion location (cortical vs. subcortical) and hemisphere (right vs. left).

Main Methods:

• Analysis of data from the Families in Recovery from Stroke Trial.
• Classification of participants based on lesion lateralization (n=274) and cortical involvement (n=158).
• NIHSS scores (measured ~13 days post-stroke) used to predict outcomes at 3 and 6 months, including physical performance, activities of daily living (ADL), instrumental ADL (IADL), cognitive function, and depressive symptoms (CES-D).

Main Results:

• NIHSS scores significantly predicted physical performance, ADL independence, and IADL independence.
• The association between NIHSS and physical performance/IADLs was weaker in patients with cortical lesions compared to those with exclusively subcortical lesions.
• Hemisphere laterality influenced the association between NIHSS and depressive symptoms (CES-D) and cognitive measures, but not physical/ADL/IADL outcomes.

Conclusions:

• The NIHSS may offer better prognostic value for stroke survivors with subcortical lesions compared to those with cortical involvement.
• NIHSS predicted depressive symptoms in right-hemisphere stroke patients but not left-hemisphere patients.
• The association between NIHSS and cognitive outcomes was minimal in patients without left-hemisphere involvement.