Reliability of IMU-Derived Temporal Gait Parameters in Neurological Diseases.

Evaluating gait is part of every neurological movement disorder assessment. Generally, the physician assesses the patient based on their experience, but nowadays inertial measurement units (IMUs) are also often integrated in the assessment. Instrumented gait analysis has a longstanding tradition and temporal parameters are used to compare patient groups or trace disease progression over time. However, the day-to-day variability needs to be considered especially in specific patient cohorts. The aim of the study was to examine day-to-day variability of temporal gait parameters of two experimental conditions in a cohort of neurogeriatric patients using data extracted from a lower back-worn IMU. We recruited 49 participants (24 women (age: 78 years ± 6 years, BMI = 25.1 kg/m2 and 25 men (age: 77 years ± 6 years, BMI = 26.5 kg/m2)) from the neurogeriatric ward. Two gait distances (4 m and 20 m) were performed during the first session and repeated the following day. To evaluate reliability, the Intraclass Correlation Coefficient (ICC2,k) and minimal detectable change (MDC) were calculated for the number of steps, step time, stride time, stance time, swing time, double limb support time, double limb support time variability, stride time variability and stride time asymmetry. The temporal gait parameters showed poor to moderate reliability with mean ICC and mean MDC95% values of 0.57 ± 0.18 and 52% ± 53%, respectively. Overall, only four out of the nine computed temporal gait parameters showed high relative reliability and good absolute reliability values. The reliability increased with walking distance. When only investigating steady-state walking during the 20 m walking condition, the relative and absolute reliability improved again. The most reliable parameters were swing time, stride time, step time and stance time. Study results demonstrate that reliability is an important factor to consider when working with IMU derived gait parameters in specific patient cohorts. This advocates for a careful parameter selection as not all parameters seem to be suitable when assessing gait in neurogeriatric patients.

Motor, cognitive and mobility deficits in 1000 geriatric patients: protocol of a quantitative observational study before and after routine clinical geriatric treatment - the ComOn-study.

BACKGROUND: Motor and cognitive deficits and consequently mobility problems are common in geriatric patients. The currently available methods for diagnosis and for the evaluation of treatment in this vulnerable cohort are limited. The aims of the ComOn (COgnitive and Motor interactions in the Older populatioN) study are (i) to define quantitative markers with clinical relevance for motor and cognitive deficits, (ii) to investigate the interaction between both motor and cognitive deficits and (iii) to assess health status as well as treatment outcome of 1000 geriatric inpatients in hospitals of Kiel (Germany), Brescia (Italy), Porto (Portugal), Curitiba (Brazil) and Bochum (Germany). METHODS: This is a prospective, explorative observational multi-center study. In addition to the comprehensive geriatric assessment, quantitative measures of reduced mobility and motor and cognitive deficits are performed before and after a two week's inpatient stay. Components of the assessment are mobile technology-based assessments of gait, balance and transfer performance, neuropsychological tests, frailty, sarcopenia, autonomic dysfunction and sensation, and questionnaires to assess behavioral deficits, activities of daily living, quality of life, fear of falling and dysphagia. Structural MRI and an unsupervised 24/7 home assessment of mobility are performed in a subgroup of participants. The study will also investigate the minimal clinically relevant change of the investigated parameters. DISCUSSION: This study will help form a better understanding of symptoms and their complex interactions and treatment effects in a large geriatric cohort.

Functional movement disorders in neurogeriatric inpatients : Underdiagnosed, often comorbid to neurodegenerative disorders and treatable.

BACKGROUND: The proportion of patients with functional movement disorders (FMD) is particularly high in neurology clinics. Treatment options have not been consistently developed, not well evaluated and not validated. This article presents the preliminary data on the prevalence and treatment response of patients with FMD who were treated within the framework of an early rehabilitative geriatric complex treatment at a university hospital for neurology. METHODS: From July 2017 to November 2018 the prevalence, demographic and clinical parameters, and response to treatment of FMD patients were documented and compared to non-FMD patients treated at the neurogeriatric ward of the University Hospital Schleswig-Holstein, in Kiel. Clinical endpoints were the Short Physical Performance Battery (SPPB) for mobility and the Barthel index for instrumented activity of daily life (iADL). RESULTS: The prevalence of FMD was 11% (19/175) and predominantly observed in women (74%). Of the FMD patients nine also had a diagnosis of either idiopathic Parkinson's disease (N = 7), dementia with Lewy bodies (N = 1) or progressive supranuclear palsy (N = 1). At admission, neither the SPPB nor the iADL differed significantly between FMD and non-FMD patients. The treatment response was comparable between the groups: SPPB change was +0.3±1.8 (mean, standard deviation) in FMD and +0.4±1.9 in non-FMD patients (p = 0.83). The iADL change was +19±15 in FMD and +18±17 in non-FMD (p = 0.83). CONCLUSION: The prevalence of FMD was unexpectedly high in the neurogeriatric ward of a German university hospital. There were comparable impairments and responses to multidisciplinary treatment in mobility and iADL between FMD and non-FMD geriatric patients, suggesting that specific and informed treatment provided by a multidisciplinary geriatric team is effective in geriatric FMD patients. Further studies of this underdiagnosed disorder in older age are warranted.