NIHSS is not enough for cognitive screening in acute stroke: A cross-sectional, retrospective study

Abstract

the aim of this study was to investigate whether the cognitive subscale of the national institute of Health Stroke Scale (NIHSS), the Cog-4, can detect cognitive deficits in acute stroke. This was a cross-sectional, retrospective study. The study sample consisted of people with stroke enrolled in an acute stroke unit. The index test Cog-4 was calculated based on admission NIHSS score. The reference standard instrument, the Montreal Cognitive Assessment (MoCA), was performed within 36-48 h of admission. Non-parametric statistics were used for data analyses. The study included 531 participants with a mean age of 69 years. The Cog-4 failed to identify cognitive deficits in 65%, 58%, and 53% of patients when the MocA thresholds for impaired cognition were set at ≤25 p, ≤23 p, and ≤19 p, respectively, were chosen for impaired cognition. The agreement between the Cog-4 and the MoCA was poor; cohen's kappa was from −0.210 to −0.109, depending on the MoCA cutoffs. The sensitivity of the Cog-4 was 35%, 42% and 48% for the MoCA thresholds for impaired cognition ≤25, ≤23 and ≤19 points, respectively. The Cog-4 has a limited ability to identify cognitive deficits in acute stroke. More structured and comprehensive tests should be employed as diagnostic tools. Cognitive difficulties are common manifestations during the acute phase of stroke and can persist after a seemingly successful neurological recovery affecting the daily lives of people who had a stroke 1,2. Cognitive deficits are linked with poor outcomes 3,4 ; thus, early identification of stroke-related cognitive impairments is important. Pinpointing the superior assessment tool for evaluating cognitive function after stroke is difficult 5. The National Institute of Health Stroke Scale (NIHSS) is a routinely used instrument for the assessment of stroke-related neurological deficits, but limited sensitivity for detecting cognitive deficits has been shown 6,7. However, Cumming et al. 8 suggested that the NIHSS subscale, the Cog-4, could be used to make a statement about cognition 8. The Cog-4 is estimated based on four items of the NIHSS-orientation, executive ability, language skills and extinction and inattention. The score range is 0-9 points, where 0 points indicates no cognitive deficits. Conflicting results have been reported regarding the capacity of Cog-4 to identify cognitive deficits after stroke 8-11. Some studies have reported that the Cog-4 cannot be considered a useful cognitive scale 9,10. Another study indicated that the Cog-4 is almost as good as other commonly used screening tools for cognition in patients with severe cognitive deficits 8. In these studies, the Cog-4 was compared with the Mini-Mental State Examination (MMSE) 8 , the Montreal Cognitive Assessment (MoCA) 10 , and follow-up assessment with the Cog-4 11. Assessments were performed within 1-4 days 10 , 90 days 9 , and 18 months 8 after stroke. It still remains unclear whether the Cog-4 can identify cognitive difficulties after stroke, especially very early after the onset of stroke. Cognitiv...

TVA-based modeling of short-term memory capacity, speed of processing and perceptual threshold in chronic stroke patients undergoing cognitive training: case-control differences, reliability, and associations with cognitive performance

“…We found no associations between NIHSS at hospital discharge, suggesting that, among patients with relatively mild strokes, the severity of the stroke as measured by NIHSS is not a strong predictor of short-term memory capacity, processing speed, nor perceptual threshold as measured by TVA in a chronic stage. These findings are in line with a recent study reporting poor predictive value of NIHSS obtained at the hospital admission for cognitive functions in the acute phase (Abzhandadze, Reinholdsson & Sunnerhagen, 2020). Further, we found no significant association between TOAST nor location of the stroke, and performance on TVA.…”

“…Clinical severity was indexed by NIHSS scores at the hospital discharge, stroke subtype was classified using the Trial of Org 10172 in Acute Stroke Treatment (TOAST; Adams et al 1993) classification system, and a coarse four-class classification of lesion location (left hemisphere, right hemisphere, bilateral and brain stem/cerebellum lesions). NIHSS have been shown to have a good predictive values for the prognosis of patients with acute cerebral infarction (Zhao et al, 2018; however, it has demonstrated limited ability to identify cognitive deficits in acute stroke (Abzhandadze, Reinholdsson & Sunnerhagen, 2020). TOAST has been shown sensitive to lesion characteristics (Kang et al, 2003); however, there is a lack of studies assessing TOAST sensitivity to cognitive functions and attentional deficits.…”

Peer Review #3 of "TVA-based modeling of short-term memory capacity, speed of processing and perceptual threshold in chronic stroke patients undergoing cognitive training: case-control differences, reliability, and associations with cognitive performance (v0.1)"

“…Manuscript to be reviewed processing speed, nor perceptual threshold as measured by TVA in a chronic stage. These findings are in line with a recent study reporting poor predictive value of NIHSS obtained at the hospital admission for cognitive functions in the acute phase (Abzhandadze et al 2020). Further, we found no significant association between TOAST nor location of the stroke, and performance on TVA.…”

Silver Jubilee of Stroke Thrombolysis With Alteplase: Evolution of the Therapeutic Window

“…This indicates that NIHSS is heavily weighted toward ACS symptoms and not PCS symptoms ( 66 , 71 ), which may explain the increased door-to-needle time noted specifically in PCS conditions in results from Australian stroke unit registry ( 66 ), resulting in extended NIHSS scale ( 72 ). Recently, NIHSS was reported as not enough to detect cognitive deficits in AIS, demanding the need for improvisation of the concerned section ( 73 ). As mentioned above, availability of various assessment scales adds to the heterogeneity in the outcome measures across the stroke trials, demanding the need for a more comprehensive scale that is acceptable across the clinical/scientific community.…”