Predictors of Long-Term Outcome of Subthalamic Stimulation in Parkinson Disease.

OBJECTIVE: This study was undertaken to identify preoperative predictive factors of long-term motor outcome in a large cohort of consecutive Parkinson disease (PD) patients with bilateral subthalamic nucleus deep brain stimulation (STN-DBS). METHODS: All consecutive PD patients who underwent bilateral STN-DBS at the Grenoble University Hospital (France) from 1993 to 2015 were evaluated before surgery, at 1 year (short-term), and in the long term after surgery. All available demographic variables, neuroimaging data, and clinical characteristics were collected. Preoperative predictors of long-term motor outcome were investigated by performing survival and univariate/multivariate Cox regression analyses. Loss of motor benefit from stimulation in the long term was defined as a reduction of less than 25% in the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) part III scores compared to the baseline off-medication scores. As a secondary objective, potential predictors of short-term motor outcome after STN-DBS were assessed by performing univariate and multivariate linear regression analyses. RESULTS: In the long-term analyses (mean follow-up = 8.4 ± 6.26 years, median = 10 years, range = 1-17 years), 138 patients were included. Preoperative higher frontal score and off-medication MDS-UPDRS part III scores predicted a better long-term motor response to stimulation, whereas the presence of vascular changes on neuroimaging predicted a worse motor outcome. In 357 patients with available 1-year follow-up, preoperative levodopa response, tremor dominant phenotype, baseline frontal score, and off-medication MDS-UPDRS part III scores predicted the short-term motor outcome. INTERPRETATION: Frontal lobe dysfunction, disease severity in the off-medication condition, and the presence of vascular changes on neuroimaging represent the main preoperative clinical predictors of long-term motor STN-DBS effects. ANN NEUROL 2021;89:587-597.

Limbic Serotonergic Plasticity Contributes to the Compensation of Apathy in Early Parkinson's Disease.

BACKGROUND: De novo Parkinson's disease (PD) patients with apathy exhibit prominent limbic serotonergic dysfunction and microstructural disarray. Whether this distinctive lesion profile at diagnosis entails different prognosis remains unknown. OBJECTIVES: To investigate the progression of dopaminergic and serotonergic dysfunction and their relation to motor and nonmotor impairment in PD patients with or without apathy at diagnosis. METHODS: Thirteen de novo apathetic and 13 nonapathetic PD patients were recruited in a longitudinal double-tracer positron emission tomography cohort study. We quantified the progression of presynaptic dopaminergic and serotonergic pathology using [11 C]PE2I for dopamine transporter and [11 C]DASB for serotonin transporter at baseline and 3 to 5 years later, using linear mixed-effect models and mediation analysis to compare the longitudinal evolution between groups for clinical impairment and region-of-interest-based analysis. RESULTS: After the initiation of dopamine replacement therapy, apathy, depression, and anxiety improved at follow-up in patients with apathy at diagnosis (n = 10) to the level of patients without apathy (n = 11). Patients had similar progression of motor impairment, whereas mild impulsive behaviors developed in both groups. Striato-pallidal and mesocorticolimbic presynaptic dopaminergic loss progressed similarly in both groups, as did serotonergic pathology in the putamen, caudate nucleus, and pallidum. Contrastingly, serotonergic innervation selectively increased in the ventral striatum and anterior cingulate cortex in apathetic patients, contributing to the reversal of apathy besides dopamine replacement therapy. CONCLUSION: Patients suffering from apathy at diagnosis exhibit compensatory changes in limbic serotonergic innervation within 5 years of diagnosis, with promising evidence that serotonergic plasticity contributes to the reversal of apathy. The relationship between serotonergic plasticity and dopaminergic treatments warrants further longitudinal investigations. © 2022 International Parkinson and Movement Disorder Society.

Long-term independence and quality of life after subthalamic stimulation in Parkinson disease.

BACKGROUND AND PURPOSE: Studies on long-term nonmotor outcomes of subthalamic nucleus stimulation in Parkinson disease (PD) are scarce. This study reports on very long-term non-motor and motor outcomes in one of the largest cohorts of people with advanced PD, treated for >10 years with subthalamic nucleus stimulation. The main outcome was to document the evolution of independence in activities of daily living. The secondary outcomes were to measure the change in quality of life, as well as non-motor and motor outcomes. METHODS: Patients were studied preoperatively, at 1 year, and beyond 10 years after subthalamic stimulation with an established protocol including motor, non-motor, and neuropsychological assessments. RESULTS: Eighty-five people with PD were included. Independence scores in the off-medication condition (measured with the Schwab & England Activities of Daily Living Scale) as well as quality of life (measured with the Parkinson's Disease Questionnaire [PDQ]-37) remained improved at longest follow-up compared to preoperatively (respectively, p < 0.001, p = 0.015). Cognitive scores, measured with the Mattis Dementia Rating Scale, significantly worsened compared to before and 1 year after surgery (p < 0.001), without significant change in depression, measured with the Beck Depression Inventory. Motor fluctuations, dyskinesias, and off dystonia remained improved at longest follow-up (p < 0.001), with a significant reduction in dopaminergic treatment (45%, p < 0.001). CONCLUSIONS: This study highlights the long-term improvement of subthalamic stimulation on independence and quality of life, despite the progression of disease and the occurrence of levodopa-resistant symptoms.

Subthalamic stimulation and neuropsychiatric symptoms in Parkinson's disease: results from a long-term follow-up cohort study.

BACKGROUND: Reports on behavioural outcomes after subthalamic nucleus deep brain stimulation in Parkinson's disease are controversial and limited to short-term data. Long-term observation in a large cohort allows a better counselling and management. METHODS: To determine whether a long-term treatment with subthalamic stimulation induces or reduces impulse control behaviours, neuropsychiatric fluctuations and apathy, 69 patients treated with subthalamic stimulation are prospectively and retrospectively assessed using Ardouin Scale of Behavior in Parkinson's Disease before and after 3-10 years of stimulation. RESULTS: At a mean follow-up of 6 years, all impulse control disorders and dopaminergic addiction were significantly decreased, apart from eating behaviour and hypersexuality. Neuropsychiatric fluctuations also significantly improved (ON euphoria: 38% of the patients before surgery and 1% after surgery, P<0.01; OFF dysphoria: 39% of the patients before surgery and 10% after surgery, P<0.01). However, apathy increased (25% of the patients after surgery and 3% before, P<0.01). With the retrospective analysis, several transient episodes of depression, apathy, anxiety and impulse control disorders occurred. CONCLUSIONS: Bilateral subthalamic nucleus stimulation was overall very effective in improving impulse control disorders and neuropsychiatric fluctuations in parkinsonian patients in the long term despite a counteracting frequent apathy. Transient episodes of impulse control disorders still occurred within the follow-up. These findings recommend a close follow-up in parkinsonian patients presenting with neuropsychiatric symptoms before deep brain stimulation surgery. CLINICAL TRIAL REGISTRATION: NCT01705418;Post-results.

Psychostimulant effect of dopaminergic treatment and addictions in Parkinson's disease.

BACKGROUND: Dopamine replacement therapy in PD has been associated with both behavioral addictions and dopamine addiction. OBJECTIVES: To investigate potential association between l-dopa induced neuropsychiatric fluctuations and addictions in PD. METHODS: A cohort of 102 patients with PD suffering from motor complications of l-dopa treatment was prospectively analyzed. We evaluated dopamine addiction, behavioral addictions, and neuropsychiatric fluctuations using the Ardouin scale of behavior in PD. RESULTS: Patients with (n = 51) or without (n = 51) neuropsychiatric fluctuations did not differ in age, disease duration, medication, or UPDRS III motor score during on and off drug condition. Patients with neuropsychiatric fluctuations had a higher H & Y stage in off-drug condition. A multivariate model showed that dopamine addiction (odds ratio: 8.9; P = 0.02) and behavioral addictions (odds ratio: 3.76; P = 0.033) were more frequent in the presence of neuropsychiatric fluctuations. Behavioral addictions and dopamine addiction were more frequent in the presence than in the absence of on-drug euphoria (46% vs. 13.9%; P < 0.001 and 27% vs 6.2 %; P = 0.003), while conversely, no association emerged between dopamine or behavioral addictions and presence of off-drug dysphoria. Patients with neuropsychiatric fluctuations had a poorer quality of life and a more frequent history of anxiety disorder. CONCLUSIONS: The psychostimulant effects of dopamine treatment during on-drug euphoria, rather than avoidance of off-drug dysphoria, appear to drive both behavioral addictions and abuse of medication. © 2017 International Parkinson and Movement Disorder Society.

Personality, dopamine, and Parkinson's disease: Insights from subthalamic stimulation.

BACKGROUND: Subthalamic stimulation improves the motor and neuropsychiatric symptoms of Parkinson's disease. However, the impact of this treatment on impulse control and personality is the subject of heavy debate. The objective of this study was to investigate personality changes after subthalamic stimulation. METHODS: Using Cloninger's biosocial model, we assessed personality in 73 Parkinson's disease patients before and 12 months after subthalamic stimulation accompanied by a drastic reduction in dopaminergic medication. Changes in psychobehavioral symptoms were measured using a battery of validated clinical scales (apathy, depression, anxiety, hyperemotionality, mania, psychosis, punding, and impulse control behaviors). RESULTS: One year after surgery, the harm avoidance personality domain total score increased compared with the baseline (+2.8; 34 patients; P < 0.001), as did 3 of its 4 subdomains: anticipatory worry (+0.7; 10 patients; P = 0.005), shyness (+0.6; 7 patients; P = 0.03), and fatigability (+1.1; 10 patients; P = 0.0014). Evolution of the shyness personality trait correlated with the decrease in dopaminergic medication. Total scores in the other personality domains remained unchanged, except for extravagance, a subdomain of novelty seeking, and persistence, a subdomain of reward dependence, which both decreased following surgery (-0.3; 7 patients; and -0.6; 9 patients; P = 0.03 and P = 0.0019, respectively). Although apathy increased, other psychobehavioral symptoms, including impulse control behaviors and neuropsychiatric nonmotor fluctuations, improved. Depression and anhedonia remained stable. Scores in hypodopaminergia and neuropsychiatric nonmotor OFF correlated with harm avoidance. Scores in hyperdopaminergia and neuropsychiatric nonmotor ON correlated with novelty seeking. CONCLUSIONS: When subthalamic stimulation is applied in Parkinson's disease, significant changes in personality traits are observed, which may be related to postoperative tapering of dopaminergic treatment. © 2017 International Parkinson and Movement Disorder Society.

The prominent role of serotonergic degeneration in apathy, anxiety and depression in de novo Parkinson's disease.

SEE SCHRAG AND POLITIS DOI101093/AWW190 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: Apathy, which can occur separately or in combination with depression and anxiety, is one of the most frequently encountered neuropsychiatric symptoms in Parkinson's disease. Pathophysiological evidence suggests that parkinsonian apathy is primarily due to a mesolimbic dopaminergic denervation, but the role of the serotonergic alteration has never been examined, despite its well-known involvement in the pathogenesis of depression and anxiety. To fill this gap, we address here the pure model of de novo Parkinson's disease, without the confounding effects of antiparkinsonian treatment. Fifteen apathetic (Lille Apathy Rating Scale scores ≥ -21) and 15 non-apathetic (-36 ≤ Lille Apathy Rating Scale scores ≤ -22) drug-naïve de novo parkinsonian patients were enrolled in the present study and underwent detailed clinical assessment and positron emission tomography imaging, using both dopaminergic [(11)C-N-(3-iodoprop-2E-enyl)-2-beta-carbomethoxy-3-beta-(4-methylphenyl)-nortropane (PE2I)] (n = 29) and serotonergic [(11)C-N,N-dimethyl-2-(-2-amino-4-cyanophenylthio)-benzylamine (DASB)] (n = 27) presynaptic transporter radioligands. Apathetic parkinsonian patients presented higher depression (P = 0.0004) and anxiety (P = 0.004) scores - as assessed using the Beck Depression Inventory and the part B of the State-Trait Anxiety Inventory, respectively - compared to the non-apathetic ones - who were not different from the age-matched healthy subjects (n = 15). Relative to the controls, the non-apathetic parkinsonian patients mainly showed dopaminergic denervation (n = 14) within the right caudate nucleus, bilateral putamen, thalamus and pallidum, while serotonergic innervation (n = 15) was fairly preserved. Apathetic parkinsonian patients exhibited, compared to controls, combined and widespread dopaminergic (n = 15) and serotonergic (n = 12) degeneration within the bilateral caudate nuclei, putamen, ventral striatum, pallidum and thalamus, but also a specific bilateral dopaminergic disruption within the substantia nigra-ventral tegmental area complex, as well as a specific serotonergic alteration within the insula, the orbitofrontal and the subgenual anterior cingulate cortices. When comparing the two parkinsonian groups, the apathetic patients mainly displayed greater serotonergic alteration in the ventral striatum, the dorsal and the subgenual parts of the anterior cingulate cortices, bilaterally, as well as in the right-sided caudate nucleus and the right-sided orbitofrontal cortex. Regression analyses also revealed that the severity of apathy was moreover mainly related to specific serotonergic lesions within the right-sided anterior caudate nucleus and the orbitofrontal cortex, while the degree of both depression and anxiety was primarily linked to serotonergic disruption within the bilateral subgenual parts and/or the right dorsal part of the anterior cingulate cortex, without prominent role of the dopaminergic degeneration in the pathogenesis of these three non-motor signs. Altogether, these findings highlight a prominent role of the serotonergic degeneration in the expression of the neuropsychiatric symptoms occurring at the onset of Parkinson's disease.

Parkinsonian apathy responds to dopaminergic stimulation of D2/D3 receptors with piribedil.

Apathy is one of the most common symptoms encountered in Parkinson's disease, and is defined as a lack of motivation accompanied by reduced goal-directed cognition, behaviour and emotional involvement. In a previous study we have described a delayed withdrawal syndrome after successful motor improvement related to subthalamic stimulation allowing for a major decrease in dopaminergic treatment. This withdrawal syndrome correlated with a diffuse mesolimbic dopaminergic denervation. To confirm our hypothesis of parkinsonian apathy being related to mesolimbic dopaminergic denervation, we performed a randomized controlled study using piribedil, a relatively selective D2/D3 dopamine agonist to treat parkinsonian apathy, using the model of postoperative apathy. A 12-week prospective, placebo-controlled, randomized, double-blinded trial was conducted in 37 patients with Parkinson's disease presenting with apathy (Starkstein Apathy Scale score > 14) following subthalamic nucleus stimulation. Patients received either piribedil up to 300 mg per day (n = 19) or placebo (n = 18) for 12 weeks. The primary end point was the improvement of apathy under treatment, as assessed by the reduction of the Starkstein Apathy Scale score in both treatment groups. Secondary end points included alleviation in depression (Beck Depression Inventory), anxiety (Beck Anxiety Inventory), improvement of quality of life (PDQ39) and anhedonia (Snaith-Hamilton Pleasure Scale). Exploratory endpoints consisted in changes of the Robert Inventory score and Hamilton depression scales. An intention to treat analysis of covariance analysis was performed to compare treatment effects (P < 0.05). The number of premature study dropouts was seven in the placebo and five in the piribedil groups, mostly related to intolerance to hypodopaminergic symptoms. At follow-up evaluation, the apathy score was reduced by 34.6% on piribedil versus 3.2% on placebo (P = 0.015). With piribedil, modifications in the Beck depression and anxiety scores were -19.8% and -22.8%, respectively versus +1.4% and -8.3% with placebo, without reaching significance level. Piribedil led to a trend towards improvement in quality of life (-16.2% versus +6.7% on placebo; P = 0.08) and anhedonia (-49% versus -5.6% on the placebo; P = 0.08). Apathy, assessed by the Robert Inventory score, improved by 46.6% on piribedil and worsened by 2.3% on placebo (P = 0.005). Depression, measured by the Hamilton score, improved in the piribedil group (P = 0.05). No significant side effects were observed. The present study provides a class II evidence of the efficacy of the dopamine agonist piribedil in the treatment of apathy in Parkinson's disease.

Subthalamic stimulation in Parkinson's disease: restoring the balance of motivated behaviours.

Addictions to dopaminergic drugs or to pleasant behaviours are frequent and potentially devastating neuropsychiatric disorders observed in Parkinson's disease. They encompass impulse control disorders, punding and dopamine dysregulation syndrome. A relationship with dopaminergic treatment is strongly suggested. Subthalamic stimulation improves motor complications and allows for drastic reductions in medication. This treatment might, therefore, be considered for patients with behavioural addictions, when attempts to reduce dopaminergic medication have failed. However, conflicting data have reported suppression, alleviation, worsening or new onset of behavioural addictions after subthalamic stimulation. Non-motor fluctuations are also a disabling feature of the disease. We prospectively investigated behaviour in a cohort of 63 patients with Parkinson's disease, before and 1 year after subthalamic stimulation using the Ardouin scale, with systematic evaluation of functioning in overall appetitive or apathetic modes, non-motor fluctuations, dopaminergic dysregulation syndrome, as well as behavioural addictions (including impulse control disorders and punding) and compulsive use of dopaminergic medication. Defined drug management included immediate postoperative discontinuation of dopamine agonists and reduction in levodopa. Motor and cognitive statuses were controlled (Unified Parkinson's Disease Rating Scale, Mattis Dementia Rating Scale, frontal score). After surgery, the OFF medication motor score improved (-45.2%), allowing for a 73% reduction in dopaminergic treatment, while overall cognitive evaluation was unchanged. Preoperative dopamine dysregulation syndrome had disappeared in 4/4, behavioural addictions in 17/17 and compulsive dopaminergic medication use in 9/9 patients. New onset of levodopa abuse occurred in one patient with surgical failure. Non-motor fluctuations were significantly reduced with improvements in off-dysphoria (P ≤ 0.001) and reduction in on-euphoria (P ≤ 0.001). There was an inversion in the number of patients functioning in an overall appetitive mode (29 before versus 2 after surgery, P ≤ 0.0001) to an overall apathetic mode (3 before versus 13 after surgery, P < 0.05). Two patients attempted suicide. Improvement in motor fluctuations is linked to the direct effect of stimulation on the sensory-motor subthalamic territory, while improvement in dyskinesias is mainly explained by an indirect effect related to the decrease in dopaminergic drugs. Our data suggest that non-motor fluctuations could similarly be directly alleviated through stimulation of the non-motor subthalamic territories, and hyperdopaminergic side effects might improve mainly due to the decrease in dopaminergic medication. We show an overall improvement in neuropsychiatric symptomatology and propose that disabling non-motor fluctuations, dopaminergic treatment abuse and drug-induced behavioural addictions in Parkinson's disease may be considered as new indications for subthalamic stimulation.

Imbalanced motivated behaviors according to motor sign asymmetry in drug-naïve Parkinson's disease.

Few studies have considered the influence of motor sign asymmetry on motivated behaviors in de novo drug-naïve Parkinson's disease (PD). We tested whether motor sign asymmetry could be associated with different motivated behavior patterns in de novo drug-naïve PD. We performed a cross-sectional study in 128 de novo drug-naïve PD patients and used the Ardouin Scale of Behavior in Parkinson's disease (ASBPD) to assess a set of motivated behaviors. We assessed motor asymmetry based on (i) side of motor onset and (ii) MDS-UPDRS motor score, then we compared right hemibody Parkinson's disease to left hemibody Parkinson's disease. According to the MDS-UPDRS motor score, patients with de novo right hemibody PD had significantly lower frequency of approach behaviors (p = 0.031), including nocturnal hyperactivity (p = 0.040), eating behavior (p = 0.040), creativity (p = 0.040), and excess of motivation (p = 0.017) than patients with de novo left hemibody PD. Patients with de novo left hemibody PD did not significantly differ from those with de novo right hemibody PD regarding avoidance behaviors including apathy, anxiety and depression. Our findings suggest that motor sign asymmetry may be associated with an imbalance between motivated behaviors in de novo drug-naïve Parkinson's disease.

Early Parkinson's Disease Phenotypes Tailored by Personality, Behavior, and Motor Symptoms.

BACKGROUND: Previous studies described a parkinsonian personality characterized as rigid, introverted, and cautious; however, little is known about personality traits in de novo Parkinson's disease (PD) patients and their relationships with motor and neuropsychiatric symptoms. OBJECTIVE: To investigate personality in de novo PD and explore its relationship with PD symptoms. METHODS: Using Cloninger's biosocial model, we assessed personality in 193 de novo PD patients. Motor and non-motor symptoms were measured using several validated scales. Cluster analysis was conducted to investigate the interrelationship of personality traits, motor, and non-motor symptoms. RESULTS: PD patients showed low novelty seeking, high harm avoidance, and normal reward dependence and persistence scores. Harm avoidance was positively correlated with the severity of depression, anxiety, and apathy (rs = [0.435, 0.676], p < 0.001) and negatively correlated with quality of life (rs = -0.492, p < 0.001). Novelty seeking, reward dependence, and persistence were negatively correlated with apathy (rs = [-0.274, -0.375], p < 0.001). Classification of patients according to personality and PD symptoms revealed 3 distinct clusters: i) neuropsychiatric phenotype (with high harm avoidance and low novelty seeking, hypodopaminergic neuropsychiatric symptoms and higher impulsivity), ii) motor phenotype (with low novelty seeking and higher motor severity), iii) benign phenotype (with low harm avoidance and high novelty seeking, reward dependence, and persistence traits clustered with lower symptoms severity and low impulsivity). CONCLUSION: Personality in early PD patients allows us to recognize 3 patients' phenotypes. Identification of such subgroups may help to better understand their natural history. Their longitudinal follow-up will allow confirming whether some personality features might influence disease evolution and treatment.

Does Motor Symptoms Asymmetry Predict Motor Outcome of Subthalamic Deep Brain Stimulation in Parkinson's Disease Patients?

Background: In Parkinson's disease (PD), the side of motor symptoms onset may influence disease progression, with a faster motor symptom progression in patients with left side lateralization. Moreover, worse neuropsychological outcomes after subthalamic nucleus deep brain stimulation (STN-DBS) have been described in patients with predominantly left-sided motor symptoms. The objective of this study was to evaluate if the body side of motor symptoms onset may predict motor outcome of bilateral STN-DBS. Methods: This retrospective study included all consecutive PD patients treated with bilateral STN-DBS at Grenoble University Hospital from 1993 to 2015. Demographic, clinical and neuroimaging data were collected before (baseline condition) and 1 year after surgery (follow-up condition). The predictive factors of motor outcome at one-year follow-up, measured by the percentage change in the MDS-UPDRS-III score, were evaluated through univariate and multivariate linear regression analysis. Results: A total of 233 patients were included with one-year follow-up after surgery [143 males (61.40%); 121 (51.90 %) right body onset; 112 (48.10%) left body onset; mean age at surgery, 55.31 ± 8.44 years; mean disease duration, 11.61 ± 3.87]. Multivariate linear regression analysis showed that the left side of motor symptoms onset did not predict motor outcome (ß = 0.093, 95% CI = -1.967 to 11.497, p = 0.164). Conclusions: In this retrospective study, the body side of motor symptoms onset did not significantly influence the one-year motor outcome in a large cohort of PD patients treated with bilateral STN-DBS.

Axial impairment and falls in Parkinson's disease: 15 years of subthalamic deep brain stimulation.

In this retrospective study, we longitudinally analyzed axial impairment and falls in people with Parkinson's disease (PD) and subthalamic nucleus deep brain stimulation (STN-DBS). Axial scores and falling frequency were examined at baseline, and 1, 10, and 15 years after surgery. Preoperative demographic and clinical data, including PD duration and severity, phenotype, motor and cognitive scales, medications, and vascular changes on neuroimaging were examined as possible risk factors through Kaplan-Meier and Cox regression analyses. Of 302 individuals examined before and at 1 year after surgery, 102 and 57 were available also at 10 and 15 years of follow-up, respectively. Axial scores were similar at baseline and at 1 year but worsened at 10 and 15 years. The prevalence rate of frequent fallers progressively increased from baseline to 15 years. Preoperative axial scores, frontal dysfunction and age at PD onset were risk factors for axial impairment progression after surgery. Axial scores, akinetic/rigid phenotype, age at disease onset and disease duration at surgery predicted frequent falls. Overall, axial signs progressively worsened over the long-term period following STN-DBS, likely related to the progression of PD, especially in a subgroup of subjects with specific risk factors.

Fatigue in de novo Parkinson's Disease: Expanding the Neuropsychiatric Triad?

BACKGROUND: Fatigue is a frequent and troublesome symptom present from the early stages of Parkinson's disease (PD). OBJECTIVE: To examine the relationship between fatigue and the neuropsychiatric triad, which includes apathy, depression, and anxiety, in de novo PD. METHODS: We performed a cross-sectional study including 197 patients with de novo PD and assessed fatigue using the Parkinson's Disease Fatigue Scale (PDFS-16). We evaluated motor status using the Unified Parkinson's Disease Rating Scale (UPDRS) part III score and evaluated neuropsychiatric status using the Ardouin Scale of Behavior in Parkinson's Disease (ASBPD). We carried out univariate and multivariate analyses to model association between motor signs, non-motor signs, and fatigue risk. RESULTS: Frequency of fatigue (28.9%) was of the same order of magnitude as that of apathy. PD patients with fatigue reported a lower quality of life than patients without fatigue (p < 0.0001). The ASBPD showed that patients with fatigue had higher scores for depressed mood (p < 0.0001), anxiety (p < 0.0001), and apathy (p < 0.0001). In the univariate analysis, fatigue score was positively correlated with apathy, depression, anxiety, and the neuropsychiatric triad as a whole, and to a lesser extent with female sex, hyperemotivity, and the UPDRS part III score. In the multivariate analysis, after adjusting for sex and motor status, the fatigue score remained significantly correlated with apathy (OR = 11.17 [4.33-28.78], p < 0.0001) and depression (OR = 4.28 [1.39-13.12], p = 0.01), but not with anxiety (OR = 0.94 [0.34-2.58], p = 0.9). CONCLUSION: We propose that the neuropsychiatric triad could be expanded to include fatigue.

Long-term Outcomes (15 Years) After Subthalamic Nucleus Deep Brain Stimulation in Patients With Parkinson Disease.

OBJECTIVE: To evaluate the effects of deep brain stimulation of the subthalamic nucleus (STN-DBS) in Parkinson disease (PD) patients on motor complications beyond 15 years after surgery. METHODS: Data about motor complications, quality of life (QoL), activities of daily living, the UPDRS motor scores, dopaminergic treatment, stimulation parameters, and side effects of STN-DBS were retrospectively retrieved and compared between before surgery, at 1 year and beyond 15 years after bilateral STN-DBS. RESULTS: Fifty-one patients with 17.06 ± 2.18 years STN-DBS follow-up were recruited. Compared to baseline, the time spent with dyskinesia and the time spent in the off state were reduced by 75% (p<0.001) and by 58.7% (p<0.001), respectively. Moreover, dopaminergic drugs were reduced by 50.6% (p<0.001). The PDQL total score, and the emotional function and social function domains improved of 13.8% (p=0.005), 13.6% (p=0.01) and 29.9% (p<0.001), respectively. Few and mostly manageable device-related adverse events were observed during the follow-up. CONCLUSIONS: STN-DBS is still effective beyond 15 years from the intervention, notably with significant improvement in motor complications and stable reduction of dopaminergic drugs. Furthermore, despite the natural continuous progression of PD with worsening of levodopa-resistant motor and non-motor symptoms over the years, STN-DBS patients could maintain an improvement in QoL. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that, for patients with PD, STN-DBS remains effective at treating motor complications 15 years after surgery.

Dementia and subthalamic deep brain stimulation in Parkinson disease: A long-term overview.

OBJECTIVES: To assess the prevalence and the cumulative incidence of dementia at short-, medium- and long-term follow-up after deep brain stimulation (DBS) of the subthalamic nucleus (STN) (at 1, 5, and 10 years) and to evaluate potential risk factors for postoperative dementia. METHODS: The presence of dementia (according to the DSM-V) was retrospectively evaluated at each postoperative follow-up in patients with Parkinson disease (PD) who underwent bilateral STN-DBS. Preoperative and perioperative risk factors of developing postoperative dementia were also investigated. Demographic data, disease features, medications, comorbidities, nonmotor symptoms, PD motor scales, neuropsychological scales at baseline, and perioperative complications were collected for each patient. RESULTS: A total of 175 patients were included, and 104 were available at 10-year follow-up. Dementia prevalence was 2.3% at 1 year, 8.5% at 5 years, and 29.8% at 10 years. Dementia cumulative incidence at 1, 5, and 10 years was 2.3%, 10.9%, and 25.7%, respectively. The corresponding dementia incidence rate was 35.6 per 1,000 person-years. Male sex, higher age, hallucinations, lower frontal score at baseline, and perioperative cerebral hemorrhage were predictors of dementia. CONCLUSIONS: In patients with PD with longstanding STN-DBS, dementia prevalence and incidence are not higher than those reported in the general PD population. Except for few patients with perioperative cerebral hemorrhage, STN-DBS is cognitively safe, and does not provide dementia risk factors in addition to those reported for PD itself. Identification of dementia predictors in this population may improve patient selection and information concerning the risk of poor cognitive outcome.

Suicide and suicide attempts after subthalamic nucleus stimulation in Parkinson disease.

OBJECTIVE: To determine the postoperative attempted and completed suicide rates after subthalamic nucleus deep brain stimulation (STN-DBS) in a single-center cohort and to determine factors associated with attempted and completed suicide. METHODS: We retrospectively included all patients with Parkinson disease (PD) who underwent bilateral STN-DBS surgery at the Grenoble University Hospital between 1993 and 2016. For each patient who committed or attempted suicide, 2 patients with PD with STN-DBS without any suicidal behaviors were matched for age (±1 year), sex, and year of surgery (±2 years). Clinical data were collected from medical records. Detailed preoperative and postoperative neuropsychological evaluations, including frontal and Beck Depression Inventory (BDI) scores, were gathered. RESULTS: A total of 534 patients with PD were included. Completed and attempted suicide percentages were 0.75% (4 of 534) and 4.11% (22 of 534), respectively. The observed suicide rate in the first postoperative year (187.20 of 100,000 per year, 1 of 534) was higher than the expected National Observatory on Suicide Risks rate adjusted for age and sex (standardized mortality ratio 8.1). This rate remained similar over the second and third postoperative years. In a comparison of the 26 patients completing/attempting suicide and the 52 controls, the first group showed more frequent history of suicidal ideation/suicide attempts and psychotic symptoms, higher percentage of family psychiatric history, higher psychiatric medication use, and higher preoperative frontal and BDI scores on neuropsychological evaluations. CONCLUSIONS: Suicide behaviors can occur after STN-DBS, especially during the first 3 years. A careful multidisciplinary assessment and long-term follow-up are recommended to recognize and treat this potentially preventable risk for mortality.

The Neuropsychiatric Fluctuations Scale for Parkinson's Disease: A Pilot Study.

BACKGROUND: Non-motor fluctuations represent a main source of disability in Parkinson's disease (PD). Among them, neuropsychiatric fluctuations are the most frequent and are often under-recognized by patients and physicians, partly because specific tools for assessment of neuropsychiatric fluctuations are lacking. OBJECTIVE: To develop a scale for detecting and evaluating the presence and the severity of neuropsychological symptoms during the ON and OFF phases of non-motor fluctuations. METHODS: Neuropsychiatric symptoms reported by PD patients in the OFF- and the ON-medication conditions were collected using different neuropsychiatric scales (BDI-II, BAI, Young, VAS, etc.). Subsequently, tree phases of a pilot study was performed for cognitive pretesting, identification of ambiguous or redundant items (item reduction), and to obtain preliminary data of acceptability of the new scale. In all the three phases, the scale was applied in both the OFF and ON condition during a levodopa challenge. RESULTS: Twenty items were selected for the final version of the neuropsychiatric fluctuation scale (NFS): ten items measured the ON neuropsychological symptoms and ten items the OFF neuropsychological manifestations. Each item rated from 0-3, providing respective subscores from 0 to 30. CONCLUSIONS: Once validated, our NFS can be used to identify and quantify neuropsychiatric fluctuations during motor fluctuations. The main novelty is that it could be used in acute settings. As such, the NFS can assess the neuropsychiatric state of the patient at the time of examination. The next step will be to validate the NFS to be used in current practice.

Impact of Mood and Behavioral Disorders on Quality of Life in Parkinson's disease.

BACKGROUND: Mood symptoms negatively affect quality of life of Parkinson's disease (PD); however little is known about the impact of behavioral disorders such as impulse control disorders, and non-motor fluctuations on quality of life. OBJECTIVE: To assess the impact of mood and behavioral disorders on quality of life in PD. METHODS: 136 (84% male) PD were included (mean age: 61 ± 8y; mean duration of disease: 8.8 ± 5.4y). Mood symptoms, behavioral disorders and non-motor fluctuations were detected and quantified using the recently validated "Ardouin Scale of Behavior in Parkinson's Disease". Motor symptoms were assessed using UPDRS and quality of life with the "39-item Parkinson's Disease Questionnaire". RESULTS: Both motor and non-motor factors significantly affected the quality of life of PD patients. Multivariate regression of the relationship between items of the quality of life questionnaire and the Ardouin Scale showed that alteration of patients' quality of life was strongly correlated with the presence of mood symptoms (such as depression, anxiety ...) and with non-motor fluctuations (especially in the OFF period). A significant correlation was also found between the number of symptoms and their severity, and the quality of life deterioration. Some behavioral disorders (compulsive buying / eating behavior) also negatively affected patient's quality of life to a lesser extent. Alternatively, excess in motivation and hobbyism behaviors had a positive impact on mobility and emotional well-being dimensions respectively of quality of life. CONCLUSIONS: This study shows the main impact of mood symptoms and non-motor fluctuations on worsening quality of life in PD.

Profile of Neuropsychiatric Symptoms in Parkinson's Disease: Surgical Candidates Compared to Controls.

BACKGROUND: Subthalamic nucleus deep brain stimulation (STN-DBS) improves motor symptoms of Parkinson's disease (PD) and motor complications of dopaminergic treatment. Whether STN-DBS should be considered when PD patients experience neuropsychiatric symptoms is controversial. Lack of systematic behavioral evaluation at baseline hampers the understanding of postoperative neuropsychiatric outcomes. OBJECTIVE: This study compares the behavioral profile of a surgical population to that in general PD. METHODS: Single center data from 234 PD surgical candidates were compared to data from 260 non-demented PD patients consulting in 13 PD expert centers at different stages of disease. The latter were considered representative of the general PD population. Neuropsychiatric symptoms were assessed using the Ardouin Scale of Behavior in PD, a guided interview quantifying changes in severity of 21 neuropsychiatric symptoms, classified into psychic non-motor fluctuations, hypo- and hyperdopaminergic behaviors. Multivariate analyses were performed to study differences in behavioral items between the two groups. RESULTS: Surgical candidates were younger, had longer disease duration and used significantly higher doses of dopaminergic drugs. After adjustment for covariates, dopaminergic addiction (OR 10.83; p = 0.002), nocturnal hyperactivity (OR 1.87; p = 0.04), excessive hobbyism (OR 2.37; p = 0.008), "excess in motivation" (OR 4.02; p <  .001), psychic OFF (2.87; p < 0.001) and psychic ON (2.10; p = 0.001) fluctuations were more frequent in the surgical candidates. Depressed mood prevailed in the general PD population (OR 0.53; p = 0.045). CONCLUSION: Behavioral complications of dopaminergic treatment are frequent in PD patients candidates for STN-DBS. They cannot be considered as contraindications for STN-DBS but must be taken into account in postoperative management.