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Parkinson’s disease (PD) represents the most common neurodegenerative movement disorder. We recently identified 16 novel genes associated with PD. In this study, we focused the attention on the common and rare variants identified in the lysosomal K+ channel TMEM175. The study includes a detailed clinical and genetic analysis of 400 cases and 300 controls. Molecular studies were performed on patient-derived fibroblasts. The functional properties of the mutant channels were assessed by patch-clamp technique and co-immunoprecipitation. We have found that TMEM175 was highly expressed in dopaminergic neurons of the substantia nigra pars compacta and in microglia of the cerebral cortex of the human brain. Four common variants were associated with PD, including two novel variants rs2290402 (c.-10C > T) and rs80114247 (c.T1022C, p.M341T), located in the Kozak consensus sequence and TM3II domain, respectively. We also disclosed 13 novel highly penetrant detrimental mutations in the TMEM175 gene associated with PD. At least nine of these mutations (p.R35C, p. R183X, p.A270T, p.P308L, p.S348L, p. L405V, p.R414W, p.P427fs, p.R481W) may be sufficient to cause the disease, and the presence of mutations of other genes correlated with an earlier disease onset. In vitro functional analysis of the ion channel encoded by the mutated TMEM175 gene revealed a loss of the K+ conductance and a reduced channel affinity for Akt. Moreover, we observed an impaired autophagic/lysosomal proteolytic flux and an increase expression of unfolded protein response markers in patient-derived fibroblasts. These data suggest that mutations in TMEM175 gene may contribute to the pathophysiology of PD.

Introduction and scope Language is one of the main tools with whom people describe their pain. The semantic value of words plays a fundamental role in the pain perception, intended as a complex process of modulation and processing in the brain. The priming effect is a cognitive process in which a certain stimulus can influence subsequent stimuli. It is therefore plausible that this effect plays a key role in the modulation and perception of pain. This study aimed to investigate the potential relationship between the semantic aspects of language, the priming effect, and the perception of pain. Methods and results A narrative review of the literature was conducted. Sixteen studies were included and categorized in four groups based on the effect of the verbal suggestion on the experimental acute pain and chronic pain and on the effect of pain-related words in free pain and post-surgical subjects. Conclusions There may be a link between language and pain, both at the behavioral and neural level. The processing of semantic information associated with pain influences the pain perception.

Postural instability (PI) is one of the latest clinical manifestations of Parkinson's disease (PD). Due to the limited therapeutic effect of pharmacological therapies, a favorable consideration has now become towards rehabilitation interventions. Thus, this study aimed to synthesize literature evidence to summarize the effects of rehabilitation interventions for improving balance in PD.We conducted a narrative review of randomized-controlled clinical trials (RCTs) comparing the effects of interventions, control interventions, and no interventions on balance-related outcomes. A comprehensive search using the MEDLINE database was conducted from January 2000 to September 2021. This review included the following causes of balance-related impairments: inability to control body weight in the base of support, impaired attention and focus on balance, postural deformities, proprioceptive deficiency, sensory-motor integration, and coordination disorders, including visual and auditory-motor coordination.20 RCTs were included in the review. Various balance-related outcomes were included. The included studies focused on the effectiveness of different rehabilitation interventions, including physical therapy, virtual reality and telerehabilitation, treadmill training, hydrotherapy, action observation training, balance and cues-training interventions, and cognitive rehabilitation.The results suggest that most of the included rehabilitation interventions have promising therapeutic effects in improving balance in PD.

Osteoporotic fractures (OF) may occur without major trauma or injury. This case reports present a spine OF in Parkinson's disease (PD) and Pisa syndrome (PS). A 75-years-old woman diagnosed with PD for 19 years and PS has been developed. She recently has acute and severe low back pain. No recent injury or fall. After clinical examination and radiograph imaging, moderate wedge compression OF at L2 was revealed without a spinal cord or nerve compression. A program of conservative treatment was applied include antiosteoporotic supplementary, 6-days of bed rest, spine orthosis, and 10-weeks of exercises. The study adapted to use the following outcomes: visual analogues scale for low back pain, wall goniometer for lateral trunk flexion, and Oswesrty disability index for disability. After the intervention, the outcomes were improved as these values: visual analogues scales 7 points, lateral trunk flexion 20°, and Oswesrty disability index 60%. The case report suggests that the posture deformity as PS in PD may increase the risk of spine OF. The conservative treatment could be beneficial and safe for the OF in PD and PS. Further studies are required to confirm the role of PD postural deformities in OF and the effectiveness of therapeutic interventions.

Purpose The aim of this study was to assess the burden and the quality of life (QoL) perceived by caregivers assisting advanced Parkinson’s disease (PD) patients. Patients and Methods Consecutive advanced PD patients treated with levodopa/carbidopa intestinal gel (LCIG) or continuous subcutaneous apomorphine infusion (CSAI) or care as usual (CU) and their care partners were recruited during routine visits according to a cross-sectional design. Caregiver’s distress was assessed by Zarit Burden Interview (ZBI) and a QoL survey to evaluate and understand the burden experienced by care partners during family and working activities. Results A total of 126 patients (53 LCIG, 19 CSAI and 54 CU) and their care partners were enrolled. The ZBI score boxplot showed that LCIG and CU populations have a similar distribution (ZBI inter-quartile range [IQR] values respectively 18–42 for LCIG and 19–43 for CU group), while the CSAI group has a wider score range (IQR 16–52). Caregivers assisting patients in treatment with LCIG have more time to perform family or household duties (p=0.0022), or to engage in leisure activities (p=0.0073) compared to CU, while no difference was found when compared to CSAI group. Approximately 50% of the care partners showed mood changes in the last 6 months and LCIG and CSAI had less impact on caregiver’s mood compared to CU. Patients treated with LCIG were more independent in taking a bath or shower without assistance and were more able to move and walk without assistance. Conclusion Care partners of advanced PD patients treated with device-aided therapies have more time for their own life and a better perception of their QoL with a tendency to an improvement of mood compared with those of patients treated with CU.

The aim of this study is to assess changes in the body distribution and the semeiology of functional motor disorder (FMD) in patients who reported only one or more than one body site affected at FMD onset. Data were obtained from the Italian Registry of Functional Motor Disorders, which included patients with a diagnosis of clinically definite FMDs. The relationship between FMD features and spread to other body sites was estimated by multivariate Cox regression analysis. We identified 201 (49%) patients who reported only one body site affected at FMD onset and 209 (51%) who reported multiple body sites affected at onset. FMD spread from the initial site to another site in 43/201 (21.4%) patients over 5.7 ± 7.1 years in those with only one site affected at FMD onset; FMD spread to an another body site in 29/209 (13.8%) over 5.5 ± 6.5 years. The spread of FMD was associated with non-motor functional symptoms and psychiatric comorbidities only in the patients with one body site affected at FMD onset. Our findings provide novel insight into the natural history of FMD. The number of body sites affected at onset does not seem to have a consistent influence on the risk of spread. Furthermore, our findings suggest that psychiatric comorbidities and non-motor functional symptoms may predict the spread of FMD symptoms, at least in patients with one body site affected at onset.

Objective\ud We aimed to describe the prevalence and clinical-demographical features of patients with functional gait disorders (FGDs) and to compare them to patients with functional motor disorders (FMDs) without FGDs (No-FGDs).\ud \ud Methods\ud In this multicenter observational study, we enrolled patients with a clinically definite diagnosis of FMDs in 25 tertiary movement disorders centers in Italy. Each subject with FMDs underwent a comprehensive clinical assessment, including screening for different subtypes of functional gait disorders. Multivariate regression models were implemented in order to estimate the adjusted odds ratio (OR; 95% confidence interval) of having FGDs in relation to sociodemographic and clinical characteristics.\ud \ud Results\ud Out of 410 FMDs, 26.6% (n = 109) of patients exhibited FGDs. The most frequent FGDs were slow gait (n = 43, 39.4%), astasia-abasia (n = 26, 23.8%), and knee buckling (n = 24, 22%). They exhibited single FGDs in 51.4% (n = 56) or complex FGDs (more than one type of FGDs) in 48.6% (n = 53) of cases. On multivariate regression analysis, the presence of FGDs was more likely associated with older age (OR 1.03, 95% CI 1.01–1.04), functional visual symptoms (OR 2.19, 95% CI 1.08–4.45), and the diagnosis of somatic symptoms disorder (OR 2.97, 95% CI 1.08–8.17). FGDs were also more likely to undergo physiotherapy (OR 1.81, 95% CI 1.08–3.03).\ud \ud Conclusions\ud People with FMDs may present with different and overlapping types of FGDs, which may occur in older age. The association of FGDs with functional visual symptoms and somatic symptoms disorder opens up to new avenues to the understanding of the neural mechanisms of these disorders.

Ataxia management is mainly based on rehabilitation, symptomatic management, and functional improvement. Therefore, it is important to comprehensively assess ataxic symptoms and their impact on function. Recently, the movement disorders society recommended four generic ataxia rating scales: scale for assessment and rating of ataxia (SARA), international cooperative ataxia rating scales, Friedreich’s ataxia rating scale (FARS), and unified multiple system atrophy rating scale (UMSARS). The aim of the study was to analyze and compare the content of the recommended ataxia rating scales by linking them to the international classification of functioning, disability and health (ICF). A total of 125 meaningful concepts from 93 items of the four included scales were linked to 57 different ICF categories. The ICF categories were distributed in body structure (n = 8), body function (n = 26), activity and participation (n = 20), and environmental factors (n = 3) components. UMSARS and FARS were the only ones that have addressed the body structure or environmental factors component. The content analysis of ataxia rating scales would help clinicians and researchers select the most appropriate scale and understand ataxic symptoms and their impact on function. It seems that SARA is the optimal scale for rapid assessment of ataxia or in busy clinical settings. UMSARS or FARS are more appropriate for the investigating the impact of ataxia on overall health, and monitoring ataxia progression and disability.

Continuous subcutaneous apomorphine infusion (CSAI) is a well-recognized therapeutic option for the management of motor fluctuations in Parkinson's disease (PD), although clinical experience suggests that most patients discontinue CSAI after a variable amount of time due to several causes and circumstances. The objective of the present study was to evaluate the reasons of CSAI discontinuation and to investigate which treatment was adopted afterwards. Two independent raters retrospectively reviewed the electronic medical record of 114 patients treated with CSAI for at least 6 months. The records were reviewed regarding efficacy, safety, and evolution of CSAI treatment. Most of PD patients on CSAI had a significant improvement in their clinical condition. Lack of improvement of dyskinesia was the most frequent causes of treatment discontinuation. The second reason for CSAI discontinuation was cognitive deterioration. At CSAI discontinuation, younger patients were more likely to undergo deep brain stimulation (DBS), while older patients and patients with cognitive impairment were more likely switched to oral therapy alone (OTA). CSAI is an effective treatment that unfortunately must be discontinued in a great number of patients with advanced PD. As older age is the main limiting factor for accessing second-level therapies at CSAI discontinuation, CSAI treatment should not be postponed to older age. CSAI might be considered a good first-line and fast strategy in patients undergoing rapid deterioration of their quality of life while waiting for DBS or levodopa/carbidopa intestinal gel therapy.

Levodopa is the standard long-term dopamine replacement therapy to treat Parkinson’s disease (PD) symptoms. With time, levodopa may induce debilitating dyskinesias (LID), the treatment of which represents a large clinically unmet need. However, time-to-LID onset varies between patients, reflecting a possible genetic component. We performed an hypothesis-free whole-exome sequencing (WES)-based screening of time-to-LID onset and attempted replication of previously published candidate gene studies. A WES association analysis was carried out in 134 PD patients in a meta-analytical framework. Replication was attempted in an independent study of 97 PD patients. Variants from previously reported candidate genes (OPRM1, COMT, BDNF) were also specifically examined. We significantly replicated, for the first time, an association of variant rs1799971 in the OPRM1 gene with time-to-LID onset. Furthermore, we identified two novel potentially functional variants, in the MAD2L2 (rs2233019) and MAP7 (rs35350783) genes, which were significantly associated at the discovery stage. In the replication study, the two variants showed direction-consistent effects but did not achieve the replication significance threshold. Our study provides the first WES results for time-to-LID onset, where we replicate association at OPRM1, and suggest new variants in MAD2L2 and MAP7 genes that are significant in discovery, but require larger datasets for replication. The results are being made publicly available to allow for independent external validation.

We aimed to study the attitude of Italian neurologists in the use of conventional MRI in patients with idiopathic adult-onset focal dystonia. Patients were included in the Italian Dystonia Registry by experts working in different Italian centers. MRI was available for 1045 of the 1471 (71%) patients included in the analysis. Using logistic regression analysis, we found that MRI was more likely to be performed in patients with cervical dystonia, spasmodic dysphonia, or non-task-specific upper limb dystonia, whereas it was less likely to be performed in patients with blepharospasm or task-specific upper limb dystonia. We did not find differences in the number of MRIs performed between neurological centers in Northern, Central, and Southern Italy. We conclude that although the diagnosis of idiopathic adult-onset dystonia is mainly based on clinical grounds, many movement disorder experts rely on MRI to confirm a diagnosis of idiopathic dystonia. We suggest that neuroimaging should be used in patients with adult-onset focal dystonia to rule out secondary forms.

Background Adult-onset focal dystonia can spread to involve one, or less frequently, two additional body regions. Spread of focal dystonia to a third body site is not fully characterized. Materials and methods We retrospectively analyzed data from the Italian Dystonia Registry, enrolling patients with segmental/multifocal dystonia involving at least two parts of the body or more. Survival analysis estimated the relationship between dystonia features and spread to a third body part. Results We identified 340 patients with segmental/multifocal dystonia involving at least two body parts. Spread of dystonia to a third body site occurred in 42/241 patients (17.4%) with focal onset and 10/99 patients (10.1%) with segmental/multifocal dystonia at onset. The former had a greater tendency to spread than patients with segmental/multifocal dystonia at onset. Gender, years of schooling, comorbidity, family history of dystonia/tremor, age at dystonia onset, and disease duration could not predict spread to a third body site. Among patients with focal onset in different body parts (cranial, cervical, and upper limb regions), there was no association between site of focal dystonia onset and risk of spread to a third body site. Discussion and conclusion Spread to a third body site occurs in a relative low percentage of patients with idiopathic adult-onset dystonia affecting two body parts. Regardless of the site of dystonia onset and of other demographic/clinical variables, focal onset seems to confer a greater risk of spread to a third body site in comparison to patients with segmental/multifocal dystonia at onset.

Introduction Functional motor disorders (FMDs) are usually categorized according to the predominant phenomenology; however, it is unclear whether this phenotypic classification mirrors the underlying pathophysiologic mechanisms. Objective To compare the characteristics of patients with different FMDs phenotypes and without co-morbid neurological disorders, aiming to answer the question of whether they represent different expressions of the same disorder or reflect distinct entities. Methods Consecutive outpatients with a clinically definite diagnosis of FMDs were included in the Italian registry of functional motor disorders (IRFMD), a multicenter data collection platform gathering several clinical and demographic variables. To the aim of the current work, data of patients with isolated FMDs were extracted. Results A total of 176 patients were included: 58 with weakness, 40 with tremor, 38 with dystonia, 23 with jerks/facial FMDs, and 17 with gait disorders. Patients with tremor and gait disorders were older than the others. Patients with functional weakness had more commonly an acute onset (87.9%) than patients with tremor and gait disorders, a shorter time lag from symptoms onset and FMDs diagnosis (2.9 ± 3.5 years) than patients with dystonia, and had more frequently associated functional sensory symptoms (51.7%) than patients with tremor, dystonia and gait disorders. Patients with dystonia complained more often of associated pain (47.4%) than patients with tremor. No other differences were noted between groups in terms of other variables including associated functional neurological symptoms, psychiatric comorbidities, and predisposing or precipitating factors. Conclusions Our data support the evidence of a large overlap between FMD phenotypes.

Peripheral markers in Parkinson’s disease (PD) represent a hot issue to provide early diagnosis and assess disease progression. The gold standard marker of PD should feature the same reliability as the pathogenic alteration, which produces the disease itself. PD is foremost a movement disorder produced by a loss of nigrostriatal dopamine innervation, in which striatal dopamine terminals are always markedly reduced in PD patients to an extent, which never overlaps with controls. Similarly, a reliable marker of PD should possess such a non-overlapping feature when compared with controls. In the present study, we provide a novel pathological hallmark, the autophagosome, which in each PD patient was always suppressed compared with each control subject. Autophagosomes were counted as microtubule-associated proteins 1A/1B light chain 3B (LC3)-positive vacuoles at ultrastructural morphometry within peripheral (blood) blood mononuclear cells (PBMC). This also provides the gold standard to assess the autophagy status. Since autophagy may play a role in the pathogenesis of PD, autophagosomes may be a disease marker, while participating in the biology of the disease. Stoichiometric measurement of α-synuclein despite significantly increased in PD patients, overlapped between PD and control patients. Although the study need to be validated in large populations, the number of autophagy vacuoles is neither related with therapy (the amount was similarly suppressed in a few de novo patients), nor the age in PD or controls.

Pisa syndrome (PS) is a postural deformity characterized by marked and reversible lateral trunk flexion. PS can be seen in Parkinson's disease (PD) and several neurodegenerative diseases. A scoping systematic review was conducted to view the therapeutic interventions for PS in PD, their effectiveness, outcome measurements, and related cofactors. Databases and manual searches were performed. Studies that evaluate the effect of interventions on PS were included. Data were extracted and categorized by the main applied therapeutic intervention. A total of 19 published and 2 unpublished studies met the inclusion criteria. Wall and traditional goniometer, kinematic analysis, and clinical observations were used to detect PS. The included studies applied the following therapeutic protocols: Deep brain stimulation (DBS), Botulinum toxin injection, posture exercises, lidocaine injection, oculomotor correction, and spinal cord stimulation. The outcomes measurements of the included studies were linked to International Classification of Functioning, Disability and Health (ICF) model. The therapeutic interventions variously improve PS outcomes at short and long-term follow-up. The interventions did not report side effects or adverse events except DBS. PS severity was related to the DBS voltage amount in one study, and one participant in another study relapsed due to DBS. There are missing reported data in terms of participants' characteristics, medication status, and side effects. The current evidence shows the available interventions for PS, outcomes measurements, and related cofactors. The interventions may be safe and beneficial for PS. Further powerful studies are required.

Background: Subthalamic deep brain stimulation (STN-DBS) effects may decrease with Parkinson’s disease (PD) progression. There is no indication if, when, and how to consider the interruption of DBS treatment in late-stage PD. The objective of the current study was to investigate the percentage of “poor stimulation responders” among late-stage PD patients for elaborating an algorithm to decide whether and when DBS discontinuation may be considered. Methods: Late-stage PD patients (Hoehn Yahr stage ≥4 and Schwab and England Scale

Background\ud Functional motor disorders (FMDs) are abnormal movements that are significantly altered by distractive maneuvers and are incongruent with movement disorders seen in typical neurological diseases.\ud \ud Objective\ud The objectives of this article are to (1) describe the clinical manifestations of FMDs, including nonmotor symptoms and occurrence of other functional neurological disorders (FND); and (2) to report the frequency of isolated and combined FMDs and their relationship with demographic and clinical variables.\ud \ud Methods\ud For this multicenter, observational study, we enrolled consecutive outpatients with a definite diagnosis of FMDs attending 25 tertiary movement disorders centers in Italy. Each patient underwent a detailed clinical evaluation with a definition of the phenotype and number of FMDs (isolated, combined) and an assessment of associated neurological and psychiatric symptoms.\ud \ud Results\ud Of 410 FMDs (71% females; mean age, 47 ± 16.1 years) the most common phenotypes were weakness and tremor. People with FMDs had higher educational levels than the general population and frequent nonmotor symptoms, especially anxiety, fatigue, and pain. Almost half of the patients with FMDs had other FNDs, such as sensory symptoms, nonepileptic seizures, and visual symptoms. Patients with combined FMDs showed a higher burden of nonmotor symptoms and more frequent FNDs. Multivariate regression analysis showed that a diagnosis of combined FMDs was more likely to be delivered by a movement disorders neurologist. Also, FMD duration, pain, insomnia, diagnosis of somatoform disease, and treatment with antipsychotics were all significantly associated with combined FMDs.\ud \ud Conclusions\ud Our findings highlight the need for multidimensional assessments in patients with FMDs given the high frequency of nonmotor symptoms and other FNDs, especially in patients with combined FMDs.

Background and purpose\ud The aims of this study were to describe the clinical manifestations of functional motor disorders (FMDs) coexisting with other neurological diseases (“comorbid FMDs”), and to compare comorbid FMDs with FMDs not overlapping with other neurological diseases (“pure FMDs”).\ud \ud Methods\ud For this multicenter observational study, we enrolled outpatients with a definite FMD diagnosis attending 25 tertiary movement disorder centers in Italy. Each patient with FMDs underwent a detailed clinical assessment including screening for other associated neurological conditions. Group comparisons (comorbid FMDs vs. pure FMDs) were performed in order to compare demographic and clinical variables. Logistic regression models were created to estimate the adjusted odds ratios (95% confidence intervals) of comorbid FMDs (dependent variable) in relation to sociodemographic and clinical characteristics (independent variables).\ud \ud Results\ud Out of 410 FMDs, 21.7% of patients (n = 89) had comorbid FMDs. The most frequent coexisting neurological diseases were migraine, cerebrovascular disease and parkinsonism. In the majority of cases (86.5%), FMDs appeared after the diagnosis of a neurological disease. Patients with comorbid FMDs were older, and more frequently had tremor, non‐neurological comorbidities, paroxysmal non‐epileptic seizures, major depressive disorders, and benzodiazepine intake. Multivariate regression analysis showed that diagnosis of comorbid FMDs was more likely associated with longer time lag until the final diagnosis of FMD, presence of tremor and non‐neurological comorbidities.\ud \ud Conclusions\ud Our findings highlight the need for prompt diagnosis of FMDs, given the relatively high frequency of associated neurological and non‐neurological diseases.

In the last decade the influence of nonmotor symptoms on the motor performance of Parkinson's disease (PD) patients has been the subject of several studies. In this chapter we focus on the role played by emotional processes that have been studied through research conducted in laboratory or clinical settings. The studies reviewed in this chapter clearly show how PD negatively influences the affective life of patients. More specifically, research on emotional processes and expressions suggests that PD patients may exhibit significant deficits in nonverbal communication, with difficulties in producing emotional facial movements and recognizing the emotions of other people. Several studies demonstrate how patients with PD may display deficits in performing emotion recognition tasks; this seems particularly true for experimental tasks involving prosodic stimuli with a negative valence. Other studies have shown mood alterations and emotional dysfunctions including depression, apathy, and anxiety as well as alexithymia.

Cervical dystonia is associated with neck pain in a significant proportion of cases, but the mechanisms underlying pain are largely unknown. In this exploratory study, we compared demographic and clinical variables in cervical dystonia patients with and without neck pain from the Italian Dystonia Registry. Univariable and multivariable logistic regression analysis indicated a higher frequency of sensory trick and a lower educational level among patients with pain.

Background Acute peripheral trauma is a controversial risk factor for idiopathic dystonia. Materials and methods We retrospectively analyzed data from the Italian Dystonia Registry regarding the occurrence of acute peripheral trauma severe enough to require medical attention in 1382 patients with adult-onset idiopathic dystonia and 200 patients with acquired adult-onset dystonia. Results Patients with idiopathic and acquired dystonia showed a similar burden of peripheral trauma in terms of the number of patients who experienced trauma (115/1382 vs. 12/200, p = 0.3) and the overall number of injuries (145 for the 1382 idiopathic patients and 14 for the 200 patients with secondary dystonia, p = 0.2). Most traumas occurred before the onset of idiopathic or secondary dystonia but only a minority of such injuries (14 in the idiopathic group, 2 in the acquired group, p = 0.6) affected the same body part as that affected by dystonia. In the idiopathic group, the elapsed time between trauma and dystonia onset was 8.1 ± 9.2 years; only six of the 145 traumas (4.1%) experienced by 5/1382 idiopathic patients (0.36%) occurred one year or less before dystonia onset; in the acquired dystonia group, the two patients experienced prior trauma to the dystonic body part 5 and 6 years before dystonia development. Discussion and conclusion Our data suggest that the contribution of peripheral acute trauma to idiopathic dystonia is negligible, if anything, and likely involves only a small subset of patients.

BACKGROUND It is well known that a deficit in inhibitory control is a hallmark of Parkinson's disease (PD). However, inhibition is not a unitary construct, and it is unclear whether patients in the early stage of the disease (Hoehn and Yahr stage 1) exhibit a deficit in outright stopping (reactive inhibition), a deficit in the ability to shape their response strategies according to the context (proactive inhibition), or both. OBJECTIVE We assessed whether PD patients at Hoehn and Yahr stage 1 show a global or selective impairment in inhibitory control. As it has been suggested that inhibition relies upon a right-lateralized pathway, we tested whether left-dominant PD patients suffered from a more severe deficit in this executive function than right-dominant PD patients. METHODS Via a reaching stop-signal task, we assessed both proactive and reactive inhibition in 17 left-dominant PD and 17 right-dominant PD patients and in 24 age-matched participants. RESULTS We found that reactive inhibition was more impaired in PD patients than in healthy participants. However, proactive inhibition was not affected. Furthermore, we found no differences between left-dominant PD and right-dominant PD patients. CONCLUSIONS For the first time, we found evidence for a deficit of reactive inhibition in the early-stage PD patients in the absence of evidence for deficits in proactive inhibition. These findings have clinical relevance as they provide critical insights on the time course of the disease. In addition, we confirmed, on a population of PD patients at Hoehn and Yahr stage 1, previous results showing that the onset of the disease does not affect inhibition. © 2019 International Parkinson and Movement Disorder Society.

ObjectiveTo perform a simultaneous evaluation of potential risk/protective factors of Parkinson disease (PD) to identify independent risk/protective factors, to assess interaction among factors, and to determine whether identified risk factors predict etiologic subtypes of PD.MethodsWe designed a large case-control study assessing 31 protective/risk factors of PD, including environmental and lifestyle factors, comorbid conditions, and drugs. The study enrolled 694 patients with PD and 640 healthy controls from 6 neurologic centers. Data were analyzed by logistic regression models, additive interaction models, and cluster analysis.ResultsThe simultaneous assessment of 31 putative risk/protective factors of PD showed that only coffee consumption (odds ratio [OR] 0.6; 95% confidence interval [CI] 0.4–0.9), smoking (OR 0.7, 95% CI 0.6–0.9), physical activity (OR 0.8, 95% CI 0.7–0.9), family history of PD (OR 3.2, 95% CI 2.2–4.8), dyspepsia (OR 1.8, 95% CI 1.3–2.4), and exposure to pesticides (OR 2.3, 95% CI1.3–4.2), oils (OR 5.6, 95% CI 2.3–13.7), metals (OR 2.8, 95% CI 1.5–5.4), and general anesthesia (OR 6.1, 95% CI 2.9–12.7) were independently associated with PD. There was no evidence of interaction among risk/protective factors, but cluster analysis identified 4 subtypes with different risk factor profiles. In group 1, all patients had a family history of PD, while dyspepsia or exposure to toxic agents was present in 30% of patients. In groups 2 and 3, a family history of PD was lacking, while exposure to toxic agents (group 2) and dyspepsia (group 3) played major roles. Group 4 consisted of patients with no risk factors.ConclusionsThis study demonstrated that 9 factors independently modify PD risk by coexisting in the same patient rather than interacting with others. Our study suggests the need for future preventive strategies aimed at reducing the coexistence of different risk factors within the same participant.