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

© The Author(s). 2020 Open Access. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.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.info:eu-repo/semantics/publishedVersio

Evaluation of the antihyperalgesic effect of tapentadol in two human evoked pain models – the TapCapMentho pilot trial

<p><b>Objective</b>: Tapentadol is effective in the treatment of neuropathic and nociceptive pain and in acute and chronic pain conditions; two mechanisms combining opioid µ-receptor agonism and noradrenergic reuptake inhibition underlie its analgesic effect.</p> <p><b>Research design and methods</b>: With this single-center, placebo-controlled, double-blind, cross-over pilot-study, we investigated the antihyperalgesic effect of a single oral dose of 100 mg immediate-release tapentadol on thermal and mechanical hyperalgesia in two human models (i.e. 0.6 % topical capsaicin and 40% topical menthol) of evoked neuropathic pain signs in healthy volunteers.</p> <p><b>Results</b>: No significant differences regarding experimentally induced heat or cold and mechanical (pinprick) hyperalgesia, as assessed by quantitative sensory testing, could be observed between a single dose of drug and placebo (thermal pain thresholds p>0.4, mechanical pain sensitivity p>0.1). Only few mild side effects of tapentadol were reported.</p> <p><b>Conclusions</b>: The discrepancy between pain models using healthy volunteers and drug trials under real acute and chronic pain conditions in patients as well as methodological aspects may have contributed to this result. The impact of these findings questions the general use of pain models as predictors for early decision making during drug development.</p> <p>The study was registered in ClinicalTrials.gov (NCT01615510).</p

Spatial Filtering of EEG Signals to Identify Periodic Brain Activity Patterns

peer reviewedLong-lasting periodic sensory stimulation is increasingly used in neuroscience to study, using electroencephalography (EEG), the cortical processes underlying perception in different modalities. This kind of stimulation can elicit synchronized periodic activity at the stimulation frequency in neuronal populations responding to the stimulus, referred to as a steady-state response (SSR). While the frequency analysis of EEG recordings is particularly well suited to capture this activity, it is limited by the intrinsic noisy nature of EEG signals and the low signal-to-noise ratio (SNR) of some responses. This paper compares and adapts spatial filtering methods for periodicity maximization to enhance the SNR of periodic EEG responses, a key condition to generalize their use as a research or clinical tool. This approach uncovers both temporal dynamics and spatial topographic patterns of SSRs, and is validated using EEG data from 15 healthy subjects exposed to periodic cool and warm stimuli

Spatial Filtering of EEG Signals to Identify Periodic Brain Activity Patterns

Long-lasting periodic sensory stimulation is increasingly used in neuroscience to study, using electroencephalography (EEG), the cortical processes underlying perception in different modalities. This kind of stimulation can elicit synchronized periodic activity at the stimulation frequency in neuronal populations responding to the stimulus, referred to as a steady-state response (SSR). While the frequency analysis of EEG recordings is particularly well suited to capture this activity, it is limited by the intrinsic noisy nature of EEG signals and the low signal-to-noise ratio (SNR) of some responses. This paper compares and adapts spatial filtering methods for periodicity maximization to enhance the SNR of periodic EEG responses, a key condition to generalize their use as a research or clinical tool. This approach uncovers both temporal dynamics and spatial topographic patterns of SSRs, and is validated using EEG data from 15 healthy subjects exposed to periodic cool and warm stimuli

Pathophysiological mechanisms of neuropathic pain: comparison of sensory phenotypes in patients and human surrogate pain models

As an indirect approach to relate previously identified sensory phenotypes of patients suffering from peripheral neuropathic pain to underlying mechanisms, we used a published sorting algorithm to estimate the prevalence of denervation, peripheral and central sensitization in 657 healthy subjects undergoing experimental models of nerve block (NB) (compression block and topical lidocaine), primary hyperalgesia (PH) (sunburn and topical capsaicin), or secondary hyperalgesia (intradermal capsaicin and electrical high-frequency stimulation), and in 902 patients suffering from neuropathic pain. Some of the data have been previously published. Randomized split-half analysis verified a good concordance with a priori mechanistic sensory profile assignment in the training (79%, Cohen κ = 0.54, n = 265) and the test set (81%, Cohen κ = 0.56, n = 279). Nerve blocks were characterized by pronounced thermal and mechanical sensory loss, but also mild pinprick hyperalgesia and paradoxical heat sensations. Primary hyperalgesia was characterized by pronounced gain for heat, pressure and pinprick pain, and mild thermal sensory loss. Secondary hyperalgesia was characterized by pronounced pinprick hyperalgesia and mild thermal sensory loss. Topical lidocaine plus topical capsaicin induced a combined phenotype of NB plus PH. Topical menthol was the only model with significant cold hyperalgesia. Sorting of the 902 patients into these mechanistic phenotypes led to a similar distribution as the original heuristic clustering (65% identity, Cohen κ = 0.44), but the denervation phenotype was more frequent than in heuristic clustering. These data suggest that sorting according to human surrogate models may be useful for mechanism-based stratification of neuropathic pain patients for future clinical trials, as encouraged by the European Medicines Agency