Introduction – Deep Brain Stimulation is an established treatment for movement disorders. Data-driven approaches like probabilistic mapping and predictive modeling are being increasingly used to optimize stimulation parameter selection. However, it remains unclear whether intra-operative test data alone can reliably inform such models. Clarifying the predictive value of intra-operative data is essential, as it may influence data collection strategies and surgical and programming protocols. Objective – This study examined whether post-operative DBS effects can be accurately predicted using intra-operative data alone or if post-operative information is required. Methods – A dataset comprising 1117 intra-operative and 1553 post-operative stimulation tests from 35 patients (14 Essential Tremor, 21 Parkinson’s Disease) was analyzed. Volumes of tissue activated (VTAs) were simulated to generate probabilistic maps, from which mapping and target anatomy-related features were extracted to train predictive classification models (low and high improvement, side effects). Model performance was assessed across scenarios linking intra- and post-operative data. Results – Intra-operative data effectively identified regions associated with optimal stimulation, highlighting their utility in guiding parameter selection (predictive accuracy ~60%). However, the predictive relationship between VTAs, probabilistic maps, and clinical outcomes differed between intra- and post-operative contexts. When trained solely on intra-operative VTAs, the model performed at a near chance level (predictive accuracy ~35%). Discussion – The study demonstrates that while intra-operative data are useful for identifying optimal target regions, they are insufficient for accurately predicting post-operative DBS outcomes. Incorporating post-operative data remains crucial for reliable and clinically meaningful DBS effect prediction.

BACKGROUND:Peripheral neuropathy has been described in Parkinson's disease (PD) patients receiving continuous levodopa delivery. Whether subcutaneous foslevodopa/foscarbidopa (fLD/fCD) infusion carries a similar risk remains unclear. CASES:We report four PD patients treated with continuous subcutaneous fLD/fCD who experienced clinical and electrophysiological worsening of peripheral neuropathy after treatment initiation. At baseline, none reported functional neuropathic symptoms, although electrophysiological evidence of mild subclinical peripheral neuropathy and/or biochemical abnormalities was present. Neuropathic symptoms developed within a few months of fLD/fCD initiation and were associated with vitamin B6 and/or B12 deficiency and persistent hyperhomocysteinemia. In all cases, electrophysiological deterioration accompanied symptoms emergence. CONCLUSIONS:Although causality cannot be established, these cases suggest that fLD/fCD infusion may be associated with aggravation of pre-existing peripheral neuropathy, despite non-enteral administration, supporting a potential systemic metabolic contribution. These findings underscore the importance of baseline assessment and longitudinal monitoring of peripheral nerve function and B-vitamin status in patients receiving fLD/fCD. Optimal vitamin supplementation strategies in this setting remain to be defined.

CONTEXT:Previous studies assessing adapted physical activity (APA) in Parkinson's disease (PD) have been very heterogeneous regarding methodology and intervention, and have generally not addressed the question of combining various types of physical activity with a long-term evaluation. OBJECTIVES:To evaluate the immediate and long-term effect of a 3-month APA program, combining endurance, resistance training and stretching on motor symptoms, body composition, cardiorespiratory function and metabolic profile in PD patients. METHODS:In this controlled trial, we randomly assigned forty-four PD patients in a 1:1 ratio to receive a 3-month APA program (APA + group, n = 22), or freely practice physical activity (APA- group, n = 22). The patients were evaluated for parkinsonian symptoms (UPDRS-III), body composition, cardiorespiratory function and metabolic profile at baseline, immediately after the end of the program (M3) and six months later (M9). RESULTS:Between baseline and M3, the mean UPDRS-III score decreased in PD patients from the APA + group whereas it increased in the APA- group (-1.2 ± 6.6 vs. +1.9 ± 8.9; p = 0.04), regardless of age, sex, disease duration, dopaminergic treatment, UPDRS-III and axial score at baseline, but these between group differences waned at M9. No between group difference was observed regarding the evolution of body composition, metabolic profile or cardiorespiratory function between baseline, M3 and M9. CONCLUSION:A 3-month APA program combining endurance and resistance training plus stretching is more efficient for improving motor symptoms in PD compared to an unstructured engagement in non-specific physical activities. However, the benefits fade away six months after discontinuation of the program. STATISTICAL ANALYSIS CONDUCTED BY:LAMBERT Céline, CHU Clermont-Ferrand, DRCI, Biostatistics Unit, Clermont-Ferrand, FRANCE. REGISTRATION NUMBER:clinicaltrials.gov number NCT02816619.

STUDY OBJECTIVES:Patients with Parkinson's disease and multiple system atrophy may be subject to sleep state dissociation. Motivated by the fortuitous observation of prominent facial muscle activity during video-polysomnography in patients with multiple system atrophy, we assessed facial motor activity and chin muscle tone during sleep in multiple system atrophy compared to Parkinson's disease and controls.METHODS:A sleep expert blinded to pathology and sleep stage retrospectively analyzed facial activity in 62 video-polysomnography (11 multiple system atrophy, 38 Parkinson's disease, and 13 controls). Facial movements were classified into six categories: "Eyes closing/opening," "Eyebrows frowning," "Raising eyebrows," "Smiling," "Other mouth movements," and "Strained face," an expression involving both the superior and inferior parts of the face. Chin electromyography activity was quantified during Rapid Eye Movement (REM) and Non-Rapid Eye Movement (NREM) sleep using the atonia index, a validated algorithm.RESULTS:Multiple system atrophy patients had an increased number of all facial movements compared to controls during NREM. "Strained face" was significantly more frequent in multiple system atrophy compared to Parkinson's disease, even after adjusting for the presence of REM sleep behavior disorder (RBD). Atonia index was lower in multiple system atrophy compared to controls and Parkinson's disease during REM and NREM sleep. This difference remained significant compared to Parkinson's disease in NREM sleep during N1 and N2 after adjusting for the presence of RBD.CONCLUSIONS:Facial movements during sleep are frequent in multiple system atrophy, "strained face" appears to be a hallmark of this condition. The presence of increased facial activity and elevated muscle tone during all stages of sleep in multiple system atrophy may be a manifestation of sleep state dissociation, reflecting more severe neurodegeneration.

Background Subthalamic nucleus (STN) deep brain stimulation (DBS) alleviates severe motor fluctuations and dyskinesia in Parkinson’s disease, but may result in speech and gait disorders. Among the suspected or demonstrated causes of these adverse effects, we focused on the topography of contact balance (CB; individual, right and left relative dual positions), a scantly studied topic, analyzing the relationships between symmetric or non-symmetric settings, and the worsening of these signs. Method An observational monocentric study was conducted on a series of 92 patients after ethical approval. CB was specified by longitudinal and transversal positions and relation to the STN (CB sub-aspects) and totalized at the patient level (patient CB). CB was deemed symmetric when the two contacts were at the same locations relative to the STN. CB was deemed asymmetric when at least one sub-aspect differed in the patient CB. Baseline and 1-year characteristics were routinely collected: (i) general, namely, Unified Parkinson’s Disease Rating Scores (UPDRS), II, III motor and IV, daily levodopa equivalent doses, and Parkinson’s Disease Questionnaire of Quality of Life (PDQ39) scores; (ii) specific, namely scores for speech (II-5 and III-18) and axial signs (II-14, III-28, III-29, and III-30). Only significant correlations were considered ( p < 0.05). Results Baseline characteristics were comparable (symmetric versus asymmetric). CB settings were related to deteriorations of speech and axial signs: communication PDQ39 and UPDRS speech and gait scores worsened exclusively with symmetric settings; the most influential CB sub-aspect was symmetric longitudinal position. Conclusion Our findings suggest that avoiding symmetric CB settings, whether by electrode positioning or shaping of electric fields, could reduce worsening of speech and gait.

Introduction The aim of this study was to create a new version of the French GTS-QOL adapted to adolescents with GTS aged 12–16 years (GTS-QOL-French-Ado) and to evaluate its psychometric properties. Methods We assessed the psychometric properties of the GTS-QOL-French-Ado in 84 adolescents (mean age 13.6 years, standard deviation 1.2) in terms of factor structure, internal consistency, reliability and convergent validity with the Child Depression Inventory (CDI), the Multidimensional Anxiety Scale for Children (MASC), the Motor tic, Obsessions and compulsions, Vocal tic Evaluation Survey (MOVES) and the French “Vécu et Santé Perçue de l’Adolescent” (VSP-A), a generic self-administered measure of health-related quality of life (HRQoL) in adolescents. Results Exploratory factor analysis of the GTS-QOL-French-Ado resulted in a 5-factor solution. The GTS-QOL-French-Ado demonstrated good acceptability with missing values per subscale ranging from 0% to 1.2%, good internal consistency for four of the five subscales with Cronbach’s alpha ranging from 0.56 to 0.87 and good test–retest reliability with intraclass correlation coefficients ranging from 0.74 (95% CI: 0.52–0.86) to 0.82 (95% CI: 0.66–0.91). Convergent validity was supported by correlations with CDI, MASC, MOVES, VSP-A and clinical variables. Discussion The GTS-QOL-French-Ado is the first disease-specific HRQoL tool for French-speaking adolescents with GTS aged 12–16 years, and shows good psychometric properties. Further psychometric testing on responsiveness to change would be of great interest.

Eating disorders (EDs) in patients with Parkinson's disease (PD) are mainly described through impulse control disorders but represent one end of the spectrum of food addiction (FA). Although not formally recognized by DSM-5, FA is well described in the literature on animal models and humans, but data on prevalence and risk factors compared with healthy controls (HCs) are lacking. We conducted a cross-sectional study including 200 patients with PD and 200 age- and gender-matched HCs. Characteristics including clinical data (features of PD/current medication) were collected. FA was rated using DSM-5 criteria and the Questionnaire on Eating and Weight Patterns-Revised (QEWP-R). Patients with PD had more EDs compared to HCs (27.0% vs. 13.0%, respectively, p < 0.001). They mainly had FA (24.5% vs. 12.0%, p = 0.001) and night eating syndrome (7.0% vs. 2.5% p = 0.03). In PD patients, FA was associated with female gender (p = 0.04) and impulsivity (higher attentional non-planning factor) but not with the dose or class of dopaminergic therapy. Vigilance is necessary, especially for PD women and in patients with specific impulsive personality traits. Counterintuitively, agonist dopaminergic treatment should not be used as an indication for screening FA in patients with PD.

Background and Objectives To determine whether patients with Parkinson disease (PD) eligible for subthalamic nucleus deep brain stimulation (STN-DBS) with probable REM sleep behavior disorder (RBD) preoperatively could be more at risk of poorer motor, nonmotor, and quality of life outcomes 12 months after surgery compared to those without RBD. Methods We analyzed the preoperative clinical profile of 448 patients with PD from a French multicentric prospective study (PREDISTIM) according to the presence or absence of probable RBD based on the RBD Single Question and RBD Screening Questionnaire. Among the 215 patients with PD with 12 months of follow-up after STN-DBS, we compared motor, cognitive, psycho-behavioral profile, and quality of life outcomes in patients with (pre-opRBD+) or without (pre-opRBD-) probable RBD preoperatively. Results At preoperative evaluation, pre-opRBD+ patients were older (61 +/- 7.2 vs 59.5 +/- 7.7 years; p = 0.02), had less motor impairment (Movement Disorder Society-sponsored version of the Unified Parkinson's Disease Rating Scale [MDS-UPDRS] III "off": 38.7 +/- 16.2 vs 43.4 +/- 7.1; p = 0.03) but more nonmotor symptoms on daily living activities (MDS-UPDRS I: 12.6 +/- 5.5 vs 10.7 +/- 5.3; p < 0.001), had more psychobehavioral manifestations (Ardouin Scale of Behavior in Parkinson's Disease total: 7.7 +/- 5.1 vs 5.1 +/- 0.4; p = 0.003), and had worse quality of life (Parkinson's Disease Questionnaire-39: 33 +/- 12 vs 29 +/- 12; p = 0.03), as compared to pre-opRBD- patients. Both pre-opRBD+ and pre-opRBD- patients had significant MDS-UPDRS IV score decrease (-37% and -33%, respectively), MDS-UPDRS III "med 'off'/stim 'on'" score decrease (-52% and -54%), and dopaminergic treatment decrease (-52% and -49%) after surgery, with no between-group difference. There was no between-group difference for cognitive and global quality of life outcomes. Conclusions In patients with PD eligible for STN-DBS, the presence of probable RBD preoperatively is not associated with a different clinical outcome 1 year after neurosurgery. Classification of Evidence This study provides Class II evidence that in patients with PD eligible for STN-DBS, the presence of probable RBD preoperatively is not associated with poorer outcomes 1 year post surgery.

Whether different mechanisms, particularly ocular pathology, could lead to the emergence of visual hallucinations (VH) (defined as false perceptions with no external stimulus) versus visual illusions (VI) (defined as a misperception of a real stimulus) in Parkinson’s disease (PD) remains debated. We assessed retinal, clinical and structural brain characteristics depending on the presence of VH or VI in PD. In this case–control study, we compared retinal thickness using optical coherence tomography (OCT), between PD patients with: VI (PD-I; n = 26), VH (PD-H; n = 28), and without VI or VH (PD-C; n = 28), and assessed demographic data, disease severity, treatment, anatomical and functional visual complaints, cognitive and visuo-perceptive functions and MRI brain volumetry for each group of PD patients. Parafoveal retina was thinner in PD-H compared to PD-C (p = 0.005) and PD-I (p = 0.009) but did not differ between PD-I and PD-C (p = 0.85). Multivariate analysis showed that 1/retinal parafoveal thinning and total brain gray matter atrophy were independently associated with the presence of VH compared to PD-I; 2/retinal parafoveal thickness, PD duration, sleep quality impairment and total brain gray matter volume were independent factors associated with the presence of VH compared to PD-C; 3/anterior ocular abnormalities were the only factor independently associated with the presence of illusions compared to PD-C. These findings reinforce the hypothesis that there may be different mechanisms contributing to VH and VI in PD, suggesting that these two entities may also have a different prognosis rather than simply lying along a continuous spectrum. Clinicaltrials.gov number NCT01114321.

•Apomorphine is used for the treatment of advanced Parkinson's disease. •The most frequent adverse event is subcutaneous nodules at the infusion site. •We report the first case of drug induced agranulocytosis to apomorphine.

Introduction The Gilles de la Tourette Syndrome–Quality of Life Scale (GTS-QOL) is a self-rated disease-specific questionnaire to assess health-related quality of life of subjects with GTS. Our aim was to perform the cross-cultural adaptation of the GTS-QOL into French and to assess its psychometric properties. Methods The GTS-QOL was cross-culturally adapted by conducting forward and backward translations, following international guidelines. The psychometric properties of the GTS-QOL-French were assessed in 109 participants aged 16 years and above with regard to factor structure, internal consistency, reliability and convergent validity with the MOVES (Motor tic, Obsessions and compulsions, Vocal tic Evaluation Survey) and the WHOQOL-BREF (World Health Organization Quality of Life Brief). Results Exploratory factor analysis of the GTS-QOL-French resulted in a 6-factor solution and did not replicate the original structure in four subscales. The results showed good acceptability (missing values per subscale ranging from 0% to 0.9%), good internal consistency (Cronbach’s alpha ranging from 0.68 to 0.94) and good test–retest reliability (intraclass correlation coefficients ranging from 0.70 to 0.81). Convergent validity with the MOVES and WHOQOL-BREF scales showed high correlations. Discussion Our study provides evidence of the good psychometric properties of the GTS-QOL-French. The cross-cultural adaptation and validation of this specific instrument will make it possible to assess health-related quality of life in French-speaking subjects with GTS. The GTS-QOL-French could be recommended for use in future research.

PURPOSE:Eating disorders are common in Parkinson's disease (PD) patients and often class in Impulse control disorders, however, little is known about their phenomenology. Specific symptoms and comorbidities were described in a group of PD patients in this preliminary study.METHODS:Over a period of 6 months, 51 PD patients who experienced significant changes in eating habits following diagnosis of PD and were interviewed during regularly scheduled follow-up visits. We assessed each patient's height and weight, impulsivity, psychological distress, current eating disorder symptoms, food addiction, food habits and craving.RESULTS:Among the PD patients who experienced modified dietary habits following diagnosis, few exhibited binge eating disorders (BED) full criteria (3.9%). However, 21.6% of patients experienced episodes of out-of-control eating with a large quantity of food in short time and 39.2% satisfied food addiction (FA) criteria without binge eating disorder. Food cravings more than once a week were experienced in approximately half of the population including all FA patients. Regarding comorbidities, FA PD patients present impulsive features and anxiety.CONCLUSIONS:This study confirms the existence of FA profile in PD patients. Eating disorders even in PD are complex and have a cross-cutting criteria related to out-of-control eating, FA, and BED. The association of anxiety with PD-related food addiction, contrary to L-dopa equivalent daily dose mean score or the presence of dopamine agonists, underline the complex sustainability of the dopaminergic brainstem support. A study on their detailed prevalence in this population could be helpful to better understand unspecified feeding or eating disorder.CLINICAL TRIAL NUMBER:DR-2012-007.NAME OF THE REGISTRY:French Committee for the Protection of Persons (CPP) & French National Commission on Computing and Liberty (CNIL).LEVEL OF EVIDENCE:Level V, descriptive study.

Background: Although dopamine replacement therapy is the main risk factor for the occurrence of Impulse Control Disorders (ICDs) in Parkinson's disease (PD), non-pharmacological risk factors for have also been identified in that population and sleep disorders could be part of them. Our objective is to determine whether Restless Legs Syndrome (RLS), that has been associated with more impulsive choices in general population regardless of dopaminergic therapy, could be associated with a specific psycho-behavioral profile and ICDs in PD. Methods: Eighty consecutive PD patients were screened for the presence of RLS in a cross-sectional study. Sleep features were evaluated during one video-polysomnography. The frequency of ICDs, according to standard criteria, together with a broad range of psycho-behavioral features using the Ardouin Scale of Behavior in PD, were compared in patients with RLS (PD-RLS, n = 30) versus without RLS (PD-nRLS, n = 50). Results: PD patients with RLS reported significantly more ICDs than those without RLS (50% versus 26%, p = 0.03), especially compulsive eating disorders, and a different psycho-behavioral profile with more hyperdopaminergic behaviors. There was no between group difference for total and dopamine agonists levodopa equivalent doses. However, age and durations of both disease and dopaminergic treatment were greater in the RLS group. Multivariate and propensity score analyses controlling for age, gender, total sleep time, disease severity, dose and duration of treatment, anxiety and depression showed that RLS was an independent predictor of ICDs in PD (OR = 5.91 [1.63; 22.1] and OR = 2.89 [1.63; 6.67] respectively). Conclusion: RLS per se could be a risk factor for impulsive behaviors in PD. (C) 2018 Elsevier B.V. All rights reserved.

Introduction: Plantar flexion of toe dystonia is very painful and leads to difficulties in walking. The objective of this study was to investigate the effect of incobotulinum toxin A (Xeomin) in the treatment of this type of dystonia in parkinsonian patients, using a randomized, double blind, placebo-controlled trial. Methods: 45 parkinsonian patients with painful dystonic plantar flexion of toes were injected either with incobotulinum toxin A (Btx group), or with placebo in two muscle targets the Flexor digitorum longus and the Flexor digitorum brevis. Three groups were compared: the first group received placebo in the Flexor digitorum longus and 100U1 of Btx in the Flexor digitorum brevis (n = 16); the second group received 100 UI of Btx in the Flexor digitorum longus and placebo in the Flexor digitorum brevis (n = 13); and the third group, 2 injections of placebo (n = 16). The patients were injected in the same way twice with an interval of 3 months. The primary endpoint was measured six weeks after injections with the Clinical Global Impression (CGI) of change. Dystonia severity and associated pain were also assessed. Results: Mean CGI was improved in the Btx group compared to the placebo group (P = 0.039). A significant reduction of pain and dystonia severity were observed in patients treated with Btx compared to baseline but no improvement was noted when compared to placebo group. No difference of efficacy was highlighted between the two injection sites. Conclusions: Btx injections are effective for improving clinical state of parkinsonian patients with plantar flexion of toe dystonia. (C) 2017 Elsevier Ltd. All rights reserved.

The Motor tic, Obsessions and compulsions, Vocal tic Evaluation Survey (MOVES) is a self-report scale suggested as a severity scale for tics and related sensory phenomena observed in Gilles de la Tourette syndrome (GTS) and recommended as a screening instrument by the Committee on Rating Scale Development of the International Parkinson’s Disease and Movement Disorder Society.

Bien que le traitement dopaminergique continu soit le facteur de risque principal d’apparition de troubles du contrôle des impulsions (TCI) dans la maladie de Parkinson Idiopathique (MPI), d’autres facteurs de risque non pharmacologiques ont été identifiés. Notre objectif est de déterminer si le syndrome des jambes sans repos (SJSR), dont l’association avec des choix plus impulsifs a été rapportée dans la population générale, indépendamment du traitement dopaminergique, pourrait être associé a un profil psycho-comportemental particulier et à des TCI dans la MPI. Quatre-vingt patients parkinsoniens consécutifs ont été inclus et évalués pour la présence de SJSR. Les paramètres du sommeil ont été étudiés au cours d’une vidéo-polysomnographie. Nous avons comparé la fréquence des TCI et d’un large éventail de caractéristiques psycho-comportementales entre les patients avec SJSR (MPI-SJSR, n = 30) et sans SJSR (MPI-nSJSR, n = 50). Les patients MPI-SJSR présentaient plus de TCI que les MPI-nSJSR (50 % versus 26 %, p = 0,03), notamment des compulsions alimentaires, ainsi qu’un profil psycho-comportemental différent avec plus de comportements hyper dopaminergiques. Les analyses multivariées et le score de propension, contrôlant les facteurs de confusion tels que l’âge, le sexe, le temps total de sommeil, la durée et la dose de traitement dopaminergique, ont montré que la présence de SJSR était un prédicteur indépendant de la présence de TCI dans la MPI (OR = 5,79 [1,63 ; 20,5] et OR = 4,89 [2,27 ; 11]). Le SJSR pourrait être per se un facteur de risque supplémentaire de comportements impulsifs dans la MPI.

We investigated whether pre-operative MRI measures of focal brain atrophy could predict cognitive decline occurring after deep brain stimulation (DBS) of the subthalamic nucleus (STN) in patients with Parkinson's disease (PD). For that purpose, we prospectively collected data of 42 consecutive patients with PD who underwent bilateral STN-DBS. Normalized brain structure volumes and cortical thicknesses were measured on pre-operative T1-weighted MRI. Patients were tested for their cognitive performances before surgery and 1 year after. After controlling for age, gender, pre-operative disease severity, change in dopaminomimetic dose after surgery and contact location, we found correlations: (1) between the variation of the total Mattis dementia rating scale (MDRS) score and left lateral ventricle volume (p=0.032), (2) between the variation of the initiation/perseveration subscore of the MDRS and the left nucleus accumbens volume (p=0.042) and the left lateral ventricle volume (p=0.017) and (3) between the variation of the backward digit-span task and the right and left superior frontal gyrus thickness (p=0.004 and p=0.007, respectively). Left nucleus accumbens atrophy was associated with decline in the initiation/perseveration subscore with the largest effect size (d=-1.64). Pre-operative left nucleus accumbens volume strongly predicted postoperative decline in the initiation/attention subscore (AUC=0.92, p<0.001, 96.3% sensitivity, 80.0% specificity, 92.9% PPV and 92.9% NPV). We conclude that the morphometric measures of brain atrophy usually associated with cognitive impairment in PD can also explain or predict a part of cognitive decline after bilateral STN-DBS. In particular, the left accumbens nucleus volume could be considered as a promising marker for guiding surgical decisions.

Routine clinical practice of Deep Brain Stimulation (DBS) enters a new era where battery-related events are challenging. The important number of primary implantations and replacements pushed industrials to develop new generations of devices. We aimed to analyze the battery lifetime of different kinds of non-rechargeable devices, manufactured by a single company (Medtronic, USA): the first generation of 4-contact neurostimulator for one DBS-lead (1 channel; Soletra®) and 8-contact neurostimulator for two DBS-leads (two channels of 4 contacts; Kinetra®); the second generation of advanced programming neurostimulator (Activa® PC, two channels of 8 contacts, and SC, 1 channel of 8 contacts). We retrospectively reviewed 281 consecutive patients operated on in a single institution (from 1995 to 2016): 584 surgeries for primary implantation or replacement of neurostimulator (infection and traumatic etiologies of battery replacement were excluded). The battery lifetime was defined as the period between the surgical implantation and the removal at battery depletion. Two hundred and eighty eight battery-lifetimes were analyzed in 157 patients suffering of Parkinson disease (n=129), essential tremor (n=19), dystonia (n=9). Exclusion criteria were: battery related, still operational (n=217); patient related, died before battery depletion (n=50); missing follow-up (n=3); and other diseases treated by DBS (n=2). Battery lifetime was analyzed using survival methods (univariate, Log-Rank test; multivariate, marginal cox model; two-sided tests) accounting for the following parameters: gender, neurological disease, age at the primary implantation, the UPDRS-score before DBS surgery, the deep brain target, battery model, mean voltage (low 4V), location of battery (abdominal or sub clavicular) and presence of an adapter for replacement of first generation (Kinetra or Soletra) by second generation model (Activa).Results: The battery lifetime was shorter in male (p=0.03) and young (p<0.001) patients suffering of essential tremor (p<0.001) and dystonia (p<0.001). High voltage reduced battery lifetime (p<0.001). The second generation device, Activa models, had shorter lifetime than first generation, Soletra and Kinetra (p<0.001). Replacement of battery decreased lifetime independently of models (p<0.001). Patient and disease characteristics, high voltage, second generation devices and replacement seem to shorten lifetime of battery.