Brain comorbidities in normal pressure hydrocephalus.

BACKGROUND AND PURPOSE: This cross-sectional study aims to compare gait changes after the cerebrospinal fluid (CSF) tap test between normal pressure hydrocephalus patients with and without brain comorbidities (NPH+ and NPH- respectively) and then to identify significant contributors to a poor CSF tap test amongst individuals with NPH+. METHODS: Gait changes (during the single task and the dual task of backward counting) were quantified before and 24 h after the CSF tap test with an optoelectronic system in 52 NPH patients (77.4 ± 6.0 years; 34.6% women). Changes after the CSF tap test in stride time variability (STV, %) were our main outcome. CSF Alzheimer's disease biomarkers, cerebrovascular white matter changes assessed with brain imaging and neurodegenerative diseases with parkinsonian syndrome represented the three individual brain comorbidities. RESULTS: Brain comorbidities were frequently identified, NPH+ patients representing 40 patients of our sample (76.9%). NPH- patients improved their STV better in the single task (delta of STV = -58.6% ± 54.3% vs. -14.1% ± 62.0%; P = 0.031) and in the dual task (delta of STV =-32.2% ± 33.7% vs. 6.3% ± 58.4%; P = 0.028) after the CSF tap test than NPH+ patients. Amongst NPH+ individuals, only comorbid Alzheimer's disease was associated with STV increase (i.e. deterioration of gait) in the dual task [ß 38.4; 95% confidence interval (5.64; 71.24); P = 0.023] after the CSF tap test, whilst it was borderline in the single task [ß 35.0; 95% confidence interval (-1.97; 71.90); P = 0.063]. CONCLUSIONS: Brain comorbidities affect gait improvement after the CSF tap test in NPH patients; this influence is driven by Alzheimer's disease-related pathology.

Postural control is associated with cognition and fear of falling in patients with multiple sclerosis.

Multiple sclerosis (MS) is a chronic inflammatory and neurodegenerative disease affecting various neurological domains, such as postural control, cognition, fear of falling, depression-anxiety, and fatigue. This study examined the associations of cognitive functions, fear of falling, depression-anxiety, and fatigue with postural control in patients with MS. Postural control (sway velocity) of 63 patients with MS (age 39.0 ± 8.9 years; %female 57%; Expanded Disability Status Scale score median (interquartile range) 2.0 (1.5)) was recorded on two platforms at stable and unstable conditions. Cognition, fear of falling, depression-anxiety, and fatigue were evaluated by a comprehensive neuropsychological assessment. The associations between these domains and postural control have been measured by multivariable linear regression (adjusted for age, gender, disability, and education). In stable condition, only working memory was associated with postural control (p < 0.05). In unstable condition, working memory, executive functions, attention/processing speed, and fear of falling were associated with postural control (p < 0.05). Specific cognitive domains and fear of falling were associated with postural control in MS patients, particularly in unstable condition. These findings highlight the association of cognitive functions and fear of falling with postural control in MS.

Improvement in executive subfunctions following cerebrospinal fluid tap test identifies idiopathic normal pressure hydrocephalus from its mimics.

BACKGROUND AND PURPOSE: Patients with idiopathic normal pressure hydrocephalus (iNPH) present cognitive deficits that overlap with other neurological conditions such as Parkinson's disease or vascular dementia, therefore mimicking iNPH. This prospective study aimed to compare cognitive performances between iNPH and iNPH mimics before and after cerebrospinal fluid (CSF) tapping. METHODS: A total of 57 patients with suspicion of iNPH (75.84 ± 6.42 years; 39% female) were included in this study (37 iNPH and 20 iNPH mimics). Neuropsychological assessments were performed before and 24 h after CSF tapping of 40 ml. Multivariate logistic regressions were used to examine the association between iNPH and cognitive functions, adjusted for age, education, baseline cognitive assessment and disease duration. RESULTS: Both groups presented the same baseline cognitive performances. After CSF tapping, iNPH patients improved their semantic (P = 0.001) and phonemic verbal fluencies (P = 0.001), whereas iNPH mimics presented similar performances to before CSF tapping. The phonemic verbal fluency (odds ratio 1.43, 95% confidence interval 1.05; 1.96) and the Color Trails Test (odds ratio 0.10, 95% confidence interval 0.01; 0.76) improvements were the two discriminative cognitive tests that identified iNPH from iNPH mimics. CONCLUSION: Improvement in executive subfunctions after CSF tapping identified iNPH patients from other neurological conditions that mimic iNPH. These findings respond to clinical issues encountered on a daily basis and would improve the diagnostic process of iNPH.

Walking while talking in patients with multiple sclerosis: the impact of specific cognitive loads.

OBJECTIVES: Gait and cognitive disorders are frequently reported in patients with multiple sclerosis, leading to decreased quality of live. The objective of this prospective study was to examine the impact of four specific cognitive tasks on gait in patients with relapsing-remitting multiple sclerosis (RRMS) with low disability. METHODS: The mean±standard deviation (SD) of walking speed, stride time and stride length were measured in 25 patients with RRMS (age: 39.46±8.32years; Expanded Disability Status Scale [EDSS] score: 1.90±1.01; disease duration: 5.62±5.12years) and in 25 age-matched controls. Gait was assessed during single task and while doing four different cognitive tasks (forward counting, backward counting, semantic verbal fluency, phonemic verbal fluency). Spatiotemporal gait parameters were recorded by a 12-camera optoelectronic system. RESULTS: Patients walked slower and with a decrease stride length during the single task and the four dual tasks than controls, except for the condition of backward counting. RRMS patients and controls presented the same cognitive performances for the four conditions during walking. EDSS score was correlated with gait speed and stride length in single task, and in the dual tasks of the backward counting and phonemic fluency. CONCLUSION: Quantitative gait assessment reveals subtle gait disorders in patients with low disability of relapsing-remitting multiple sclerosis. The impact of different cognitive domains on gait induces specific gait disturbances that highlight the strong interaction between gait and cognition.

Adapted timed up and go: a rapid clinical test to assess gait and cognition in multiple sclerosis.

BACKGROUND/AIMS: To measure the Timed Up and Go (TUG), imagined TUG (iTUG), and the difference of time between these two tests (delta time) in 20 patients with relapsing-remitting multiple sclerosis (RRMS) and 20 healthy age-matched controls and to examine whether an association with cognitive functions, motor impairment, and behavioral changes can be determined. METHODS: The mean ± SD of TUG, iTUG and delta time were used as outcomes. Spatiotemporal gait parameters were recorded by a 12-camera optoelectronic system during straight walking at usual self-selected speed. Cognitive functions were assessed by a standardized neuropsychological examination. RESULTS: Patients performed the TUG slower than the controls (10.00 ± 1.70 s vs. 8.71 ± 1.04 s, p = 0.01, respectively). The TUG was correlated with gait parameters, cognitive functions, and behavior, whereas delta time was correlated only with cognitive functions. CONCLUSION: TUG represents an interesting test to reveal subtle deficits in RRMS patients with low disability and is related to motor, cognitive, and behavioral functioning. Combining with the TUG, delta time could easily give additional information on specific cognitive functions in the assessment of patients with RRMS.