David Devos

Bio: David Devos is an academic researcher from university of lille. The author has contributed to research in topics: Parkinson's disease & Medicine. The author has an hindex of 49, co-authored 216 publications receiving 7982 citations. Previous affiliations of David Devos include Centre national de la recherche scientifique & University of Lille Nord de France.

The Lille apathy rating scale (LARS), a new instrument for detecting and quantifying apathy: validation in Parkinson’s disease

Abstract: Background: Apathy is usually defined as reduced interest and participation in various activities. It is a frequent consequence of neurological and psychiatric disorders. Although various scoring methods have been proposed, there is a lack of validated, standardised instruments for detecting apathy and assessing its severity. Objective: To develop an apathy rating scale using a structured standardised interview capable of distinguishing between the condition’s various features. Methods: The Lille Apathy Rating Scale (LARS) is based on a structured interview. It includes 33 items, divided into nine domains. Responses are scored on a dichotomous scale. The participants used to validate the scale consisted of 159 patients with probable Parkinson’s disease and 58 healthy control subjects. The Marin Apathy Scale, the Montgomery and Asberg Depression Rating Scale, and the Mattis Dementia Rating Scale were also administered. Results: Principal component analysis showed that the LARS probed a single construct which forms the root of an oblique factor structure reflecting four dimensions: intellectual curiosity, self awareness, emotion, and action initiation. The main psychometric properties of the LARS (internal consistency, inter-rater and test-retest reliability) were satisfactory. Concurrent validity was evaluated by reference to the Marin scale and to judgements provided by expert clinicians. Conclusions: Standard validity indices showed that the LARS is sensitive and capable of distinguishing between apathy and depression. As a screening tool, the scale is able to support dichotomous judgements accurately and, when greater measurement sensitivity is required, also determine the severity of apathy within a four category classification.

STN-DBS frequency effects on freezing of gait in advanced Parkinson disease

Abstract: Background: Severe gait disturbances and freezing episodes (frequently resistant to optimal dopaminergic treatment) often appear in advanced Parkinson disease (PD). Even several years after initiation, high-frequency subthalamic nucleus deep brain stimulation (STN-DBS) is still very effective for controlling segmental symptoms. However, there are no long-term data on the management of gait disorders and freezing in STN-DBS. Objectives: To compare the effects of various STN-DBS parameters on freezing of gait and to determine whether such effects are more related to stimulation energy (usual voltages vs high voltages at 130 Hz) or frequency (130 Hz vs approximately half this frequency: 60 Hz). Methods: We blindly assessed STN-DBS parameters in 13 PD patients reporting severe gait disorders. We compared the effects on gait of two different voltages (the patient’s usual voltage [median 3 volts] and a high voltage [median 3.7 volts]) and two different frequencies (60 and 130 Hz, while maintaining the same total energy delivered) vs “off-stimulation” conditions. Results: The number of freezing episodes was significantly lower at the 60-Hz “high voltage/ equivalent energy” and higher at the 130-Hz/high voltage than for “off stimulation.” The slight improvement in the Unified Parkinson’s Disease Rating Scale motor score observed (at 130 Hz) did not achieve statistical significance. Conclusions: Our results prompt consideration of a new strategy for two-stage subthalamic nucleus deep brain stimulation (STN-DBS) frequency optimization, with stimulation at 130 Hz and the usual voltage during the initial years of STN-DBS and then at 60 Hz at a high voltage in Parkinson disease patients who develop severe gait disorders. Neurology ® 2008;71:80–84

Systematic review of levodopa dose equivalency reporting in Parkinson's disease

Abstract: Interpretation of clinical trials comparing different drug regimens for Parkinson's disease (PD) is complicated by the different dose intensities used: higher doses of levodopa and, possibly, other drugs produce better symptomatic control but more late complications. To address this problem, conversion factors have been calculated for antiparkinsonian drugs that yield a total daily levodopa equivalent dose (LED). LED estimates vary, so we undertook a systematic review of studies reporting LEDs to provide standardized formulae. Electronic database and hand searching of references identified 56 primary reports of LED estimates. Data were extracted and the mean and modal LEDs calculated. This yielded a standardized LED for each drug, providing a useful tool to express dose intensity of different antiparkinsonian drug regimens on a single scale. Using these conversion formulae to report LEDs would improve the consistency of reporting and assist the interpretation of clinical trials comparing different PD medications.

Molecular mechanisms of cell death: recommendations of the Nomenclature Committee on Cell Death 2018.

Abstract: Over the past decade, the Nomenclature Committee on Cell Death (NCCD) has formulated guidelines for the definition and interpretation of cell death from morphological, biochemical, and functional perspectives. Since the field continues to expand and novel mechanisms that orchestrate multiple cell death pathways are unveiled, we propose an updated classification of cell death subroutines focusing on mechanistic and essential (as opposed to correlative and dispensable) aspects of the process. As we provide molecularly oriented definitions of terms including intrinsic apoptosis, extrinsic apoptosis, mitochondrial permeability transition (MPT)-driven necrosis, necroptosis, ferroptosis, pyroptosis, parthanatos, entotic cell death, NETotic cell death, lysosome-dependent cell death, autophagy-dependent cell death, immunogenic cell death, cellular senescence, and mitotic catastrophe, we discuss the utility of neologisms that refer to highly specialized instances of these processes. The mission of the NCCD is to provide a widely accepted nomenclature on cell death in support of the continued development of the field.