Development and Validation of the Dystonia-Pain Classification System: A Multicenter Study.

BACKGROUND: Dystonia is associated with disabling nonmotor symptoms like chronic pain (CP), which is prevalent in dystonia and significantly impacts the quality of life (QoL). There is no validated tool for assessing CP in dystonia, which substantially hampers pain management. OBJECTIVE: The aim was to develop a CP classification and scoring system for dystonia. METHODS: A multidisciplinary group was established to develop the Dystonia-Pain Classification System (Dystonia-PCS). The classification of CP as related or unrelated to dystonia was followed by the assessment of pain severity score, encompassing pain intensity, frequency, and impact on daily living. Then, consecutive patients with inherited/idiopathic dystonia of different spatial distribution were recruited in a cross-sectional multicenter validation study. Dystonia-PCS was compared to validated pain, mood, QoL, and dystonia scales (Brief Pain Inventory, Douleur Neuropathique-4 questionnaire, European QoL-5 Dimensions-3 Level Version, and Burke-Fahn-Marsden Dystonia Rating Scale). RESULTS: CP was present in 81 of 123 recruited patients, being directly related to dystonia in 82.7%, aggravated by dystonia in 8.8%, and nonrelated to dystonia in 7.5%. Dystonia-PCS had excellent intra-rater (Intraclass Correlation Coefficient - ICC: 0.941) and inter-rater (ICC: 0.867) reliability. In addition, pain severity score correlated with European QoL-5 Dimensions-3 Level Version's pain subscore (r = 0.635, P < 0.001) and the Brief Pain Inventory's severity and interference scores (r = 0.553, P < 0.001 and r = 0.609, P < 0.001, respectively). CONCLUSIONS: Dystonia-PCS is a reliable tool to categorize and quantify CP impact in dystonia and will help improve clinical trial design and management of CP in patients affected by this disorder. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

A systematic review and meta-analysis on the association between orthostatic hypotension and mild cognitive impairment and dementia in Parkinson's disease.

BACKGROUND: Cognitive impairment is a frequent disabling feature of Parkinson's disease (PD). Orthostatic hypotension (OH) is treatable and may be a risk factor for cognitive impairment. OBJECTIVE: We conducted a systematic review and meta-analysis to examine the relationship between OH with PD-associated minimal cognitive impairment (PD-MCI) and dementia (PDD) and assess the mitigating effects of potential confounding factors. METHODS: Observational studies published in English, Spanish, French, or Portuguese up to January 2022 were searched for in PubMed, EBSCO, and SciELO databases. The primary aim of this study was to revise the association between OH with PD-MCI and PDD. Alongside, we assessed OH as related to cognitive rating scales. Fixed and random models were fitted. Meta-regression was used to assess the mitigating effects of confounding variables. RESULTS: We identified 18 studies that reported OH association with PDD or PD-MCI, 15 of them reporting OH association with cognitive rating scales. OH was significantly associated with PDD/PD-MCI (OR, 95% CI: 3.31, 2.16-5.08; k = 18, n = 2251; p < 0.01). OH association with PDD (4.64, 2.68-8.02; k = 13, n = 1194; p < 0.01) was stronger than with PD-MCI (1.82, 0.92-3.58; k = 5, n = 1056; p = NS). The association between OH and PD-MCI/PDD was stronger in studies with a higher proportion of women and in those with a lower frequency of supine hypertension. Global cognition rating scale scores were lower in patients with OH (SMD, 95% CI: - 0.55, - 0.83/ - 0.26; k = 12, n = 1427; p < 0.01). CONCLUSIONS: Orthostatic hypotension shows as a significant risk factor for cognitive impairment in PD, especially in women and patients not suffering from hypertension.

Assessment of Ataxia Rating Scales and Cerebellar Functional Tests: Critique and Recommendations.

BACKGROUND: We assessed the clinimetric properties of ataxia rating scales and functional tests, and made recommendations regarding their use. METHODS: A systematic literature search was conducted to identify the instruments used to rate ataxia symptoms. The identified rating scales and functional ability tests were reviewed and ranked by the panel as "recommended," "suggested," or "listed" for the assessment of patients with discrete cerebellar disorders, using previously established criteria. RESULTS: We reviewed 14 instruments (9 rating scales and 5 functional tests). "Recommended" rating scales for the assessment of symptoms severity were: for Friedreich's ataxia, the Friedreich's Ataxia Rating Scale, the International Cooperative Ataxia Rating Scale (ICARS), and the Scale for the Assessment and Rating of Ataxia (SARA); for spinocerebellar ataxias, ICARS and SARA; for ataxia telangiectasia: ICARS and SARA; for brain tumors, SARA; for congenital disorder of glycosylation-phosphomannomutase-2 deficiency, ICARS; for cerebellar symptoms in multiple sclerosis, ICARS; for cerebellar symptoms in multiple system atrophy: Unified Multiple System Atrophy Rating Scale and ICARS; and for fragile X-associated tremor ataxia syndrome, ICARS. "Recommended" functional tests were: for Friedreich's ataxia, Ataxia Functional Composite Score and Composite Cerebellar Functional Severity Score; and for spinocerebellar ataxias, Ataxia Functional Composite Score, Composite Cerebellar Functional Severity Score, and SCA Functional Index. CONCLUSIONS: We identified some "recommended" scales and functional tests for the assessment of patients with major hereditary ataxias and other cerebellar disorders. The main limitations of these instruments include the limited assessment of patients in the more severe end of the spectrum and children. Further research in these populations is warranted. © 2020 International Parkinson and Movement Disorder Society.

Fluoxetine for the Symptomatic Treatment of Multiple System Atrophy: The MSA-FLUO Trial.

BACKGROUND: There are no effective treatments for multiple system atrophy (MSA). OBJECTIVE: The objective of this study was to assess the efficacy and safety of the serotonin reuptake inhibitor fluoxetine (40 mg/d) for the symptomatic treatment of MSA. METHODS: This was a double-blind, parallel-group, placebo-controlled, randomized trial in patients with "probable" MSA. The primary outcome was the change from baseline to week 12 in the mean total score of the Unified MSA Rating Scale (UMSARS Parts I + II). Secondary outcomes included change from baseline to week 6 in total UMSARS, and change from baseline to week 12 in the Scales for Outcomes in Parkinson Disease-Autonomic Dysfunction, Beck Depression Inventory, and different domains of the MSA-Quality of Life Questionnaire. Exploratory outcomes included change from baseline to week 12 in the UMSARS Parts I and II separately and change from baseline to week 24 in the total UMSARS score. RESULTS: A total of 81 patients were randomly assigned, with no significant difference in the primary outcome (-2.13 units [95% confidence interval, CI, -4.55 to 0.29]; P = 0.08). There was a greater reduction on fluoxetine in the change from baseline to 12-week in UMSARS Part II (exploratory outcome: -1.41 units [95% CI, -2.84; 0.03]; p = 0.05) and in MSA-QoL emotional/social dimension (secondary outcome: -6.99 units [95% CI, -13.40; -0.56]; p < 0.03). A total of 5 deaths occurred (3 on fluoxetine and 2 on placebo). CONCLUSION: The MSA-FLUO failed to demonstrate fluoxetine superiority over placebo on the total UMSARS score, whereas trends in motor and emotional secondary/exploratory outcomes deserve further investigation. © 2021 International Parkinson and Movement Disorder Society.

Excessive buccal saliva in patients with Parkinson's disease of the French COPARK cohort.

We describe excessive buccal saliva (EBS) prevalence in patients with Parkinson's Disease (PD) and controls of the COPARK study, its changes between "ON" and OFF" conditions and over time, its impact on Health-related Quality of life (HRQoL), and factors associated with this condition. We studied 671 ambulatory PD patients and 177 age/sex-matched controls. We defined "sialorrhea" as UPDRS item #6 (salivation) = 1 or 2; and "drooling" as item #6 = 3 or 4. SCOPA-Aut drooling score (item #2) was also available in a subset (45%) of the cohort. HRQoL was assessed by the PDQ-39 and SF-36 scales. Twenty-four months' follow-up data were available in 401/671 patients. EBS as assessed by UPDRS was present in 38% of PD patients in the "ON" condition ("Sialorrhea": 35%; "drooling": 3%). There were also more PD patients reporting "drooling" than controls according to the SCOPA-Aut (49% vs 19%, p < 0.01). UPDRS salivation score was worse in the "OFF" vs "ON" condition in PD patients with motor fluctuations (0.90 ± 0.94 vs 0.54 ± 0.79, p < 0.01). UPDRS salivation score worsened after ~ 24 months of follow-up (0.47 ± 0.70 vs 0.64 ± 0.81, p < 0.01). Worse PDQ-39 scores were observed in PD patients with EBS in bivariate but not in multivariate analyses. EBS was directly related to PD duration and severity, male gender, dysphagia, hypomimia, and autonomic dysfunction (logistic regression). EBS was more frequent in PD patients than controls, worsened in the "OFF" condition and after ~ 24 months of follow-up, moderately affected HRQoL, and was correlated with indices of bradykinesia, dysphagia, and autonomic dysfunction.

Prevalence and factors related to orthostatic syndromes in recently diagnosed, drug-naïve patients with Parkinson disease.

PURPOSE: The aim of this study was to explore the prevalence of and factors related to orthostatic syndromes in recently diagnosed drug-naïve patients with Parkinson disease (PD). METHODS: This was a cross-sectional study that included 217 drug-naïve patients with PD and 108 sex- and age-matched non-parkinsonian controls from the Parkinson's Progression Markers Initiative (PPMI) prospective cohort study who were devoid of diabetes, alcoholism, polyneuropathy, amyloidosis, and hypotension-inducing drugs. Orthostatic symptoms were evaluated using the Scales for Outcomes in PD-Autonomic Dysfunction (SCOPA-AUT). Ioflupane-I123 single-photon emission computerized tomography was used to evaluate striatal dopamine active transporter (DaT) levels. Blood pressure was assessed both in the supine position and 1-3 min after the switch to a standing position. Orthostatic hypotension (OH) was defined by international consensus, and orthostatic intolerance (OI) was defined as the presence of orthostatic symptoms in the absence of OH. RESULTS: Compared with non-parkinsonian controls, patients with PD experienced a mild fall in systolic blood pressure upon standing (p = 0.082). The prevalence of OH was 11.1% in PD patients and 5.6% in controls (p = 0.109). The prevalence of OI was higher in patients with PD than in controls (31.3 vs. 13.3%; p = 0.003). Logistic regression revealed that OH and OI were related to a lower striatal DaT level and higher SCOPA-AUT gastrointestinal score. CONCLUSIONS: Orthostatic syndromes were common in the recently diagnosed drug-naïve patients with PD enrolled in the study, but only the prevalence of OI was higher in PD patients than in the non-parkinsonian controls. Unlike motor or functional disability indicators, markers of dopaminergic striatal deficit and gastrointestinal dysfunction were associated with OH and OI.

Role of Astrocytic Dysfunction in the Pathogenesis of Parkinson's Disease Animal Models from a Molecular Signaling Perspective.

Despite the fact that astrocytes are the most abundant glial cells, critical for brain function, few studies have dealt with their possible role in neurodegenerative diseases like Parkinson's disease (PD). This article explores relevant evidence on the involvement of astrocytes in experimental PD neurodegeneration from a molecular signaling perspective. For a long time, astrocytic proliferation was merely considered a byproduct of neuroinflammation, but by the time being, it is clear that astrocytic dysfunction plays a far more important role in PD pathophysiology. Indeed, ongoing experimental evidence suggests the importance of astrocytes and dopaminergic neurons' cross-linking signaling pathways. The Wnt-1 (wingless-type MMTV integration site family, member 1) pathway regulates several processes including neuron survival, synapse plasticity, and neurogenesis. In PD animal models, Frizzled (Fzd) neuronal receptors' activation by the Wnt-1 normally released by astrocytes following injuries leads to ß-catenin-dependent gene expression, favoring neuron survival and viability. The transient receptor potential vanilloid 1 (TRPV1) capsaicin receptor also participates in experimental PD genesis. Activation of astrocyte TRPV1 receptors by noxious stimuli results in reduced inflammatory response and increased ciliary neurotrophic factor (CNTF) synthesis, which enhances neuronal survival and differentiation. Another major pathway involves IκB kinase (IKK) downregulation by ARL6ip5 (ADP-ribosylation-like factor 6 interacting protein 5, encoded by the cell differentiation-associated, JWA, gene). Typically, IKK releases the proinflammatory NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) molecule from its inhibitor. Therefore, by downregulating NF-κB inhibitor, ARL6ip5 promotes an anti-inflammatory response. The evidence provided by neurotoxin-induced PD animal models guarantees further research on the neuroprotective potential of normalizing astrocyte function in PD.

Update on treatments for nonmotor symptoms of Parkinson's disease-an evidence-based medicine review.

OBJECTIVE: To update evidence-based medicine recommendations for treating nonmotor symptoms in Parkinson's disease (PD). BACKGROUND: The International Parkinson and Movement Disorder Society Evidence-Based Medicine Committee's recommendations for treatments of PD were first published in 2002, updated in 2011, and now updated again through December 31, 2016. METHODS: Level I studies testing pharmacological, surgical, or nonpharmacological interventions for the treatment of nonmotor symptoms in PD were reviewed. Criteria for inclusion and quality scoring were as previously reported. The disorders covered were a range of neuropsychiatric symptoms, autonomic dysfunction, disorders of sleep and wakefulness, pain, fatigue, impaired olfaction, and ophthalmologic dysfunction. Clinical efficacy, implications for clinical practice, and safety conclusions are reported. RESULTS: A total of 37 new studies qualified for review. There were no randomized controlled trials that met inclusion criteria for the treatment of anxiety disorders, rapid eye movement sleep behavior disorder, excessive sweating, impaired olfaction, or ophthalmologic dysfunction. We identified clinically useful or possibly useful interventions for the treatment of depression, apathy, impulse control and related disorders, dementia, psychosis, insomnia, daytime sleepiness, drooling, orthostatic hypotension, gastrointestinal dysfunction, urinary dysfunction, erectile dysfunction, fatigue, and pain. There were no clinically useful interventions identified to treat non-dementia-level cognitive impairment. CONCLUSIONS: The evidence base for treating a range of nonmotor symptoms in PD has grown substantially in recent years. However, treatment options overall remain limited given the high prevalence and adverse impact of these disorders, so the development and testing of new treatments for nonmotor symptoms in PD remains a top priority. © 2019 International Parkinson and Movement Disorder Society.

Efficacy and safety of amantadine for the treatment of L-DOPA-induced dyskinesia.

L-DOPA induced dyskinesias (LIDs) may affect up to 40% of Parkinson's disease (PD) and impact negatively health-related quality of life. Amantadine has demonstrated significant antidyskinetic effects in animal PD models and in randomized double-blind placebo-controlled trials (RCTs) in patients with PD. These effects are thought to be related to the blockade of NMDA receptors modulating cortico-striatal glutamatergic-dopaminergic interactions involved in the genesis of LIDs. There are three pharmaceutical forms of amantadine currently available in the market: an oral immediate-release (IR) formulation, which is widely available; an extended-release (ER) formulation (ADS-5102) which has been recently developed and approved by the FDA; and an intravenous infusion (IV) solution, which is not commonly used in clinical practice. RCTs with amantadine IR or ER, involving more than 650 patients have shown consistent and long-lasting reductions in LIDs. Interestingly, ADS-5102 not only reduced LIDs, but also reduced significantly at the same time the duration of daily OFF-time, a unique finding compared with other antiparkinsonian medications that usually reduce time spent OFF at the cost of worsening of LIDs. Amantadine IR might also have possible effects on other PD symptoms such as apathy or fatigue. The most common adverse reactions with amantadine are constipation, cardiovascular dysfunction including QT prolongation, orthostatic hypotension and edema, neuropsychiatric symptoms such as hallucinations, confusion and delirium, nausea and livedo reticularis. Corneal degeneration is rare but critical. In summary, amantadine immediate and extended-release are effective and safe for the treatment of LIDs.

Comparison of Olfactory Identification Patterns among Parkinson's Disease Patients from Different Countries.

Olfactory function assessment is an important screening tool and also may differentiate Parkinson's disease (PD) patients from other parkinsonisms, including nondegenerative ones, such as, normal pressure hydrocephalus, vascular, drug induced, or infectious parkinsonism. Several authors in different countries have reported various sets of odors that best differentiate between these conditions. It is debated if distinctive patterns of "restrictive" or "selective" hyposmia in PD may be affected by cultural aspects. To compare the olfactory identification function in PD across different countries, we analyzed Sniffin' Sticks identification task results between 112 PD patients from Argentina and previously reported data of PD patients from Brazil (106 patients), the Netherlands (400 patients), Germany (40 patients), China (110 patients), and Sri Lanka (89 patients). Categorical principal component analysis (CATPCA) was performed to find components reflecting groups of odors similarly perceived across subjects. CATPCA analysis found 2 components for each group which shared 10 out of 16 odors amongst each other. We found that only the shared items of component 2 (orange, mint, banana, garlic, coffee, cloves, and fish) showed uniform results across all of the included countries, whereas variations in component 1 (licorice, turpentine, and apple) were attributed mostly to differences across control groups.

New treatments for levodopa-induced motor complications.

Levodopa (l-dopa)-induced motor complications, including motor fluctuations and dyskinesia, affect almost all patients with Parkinson's disease (PD) at some point during the disease course, with relevant implications in global health status. Various dopaminergic and nondopaminergic pharmacological approaches as well as more invasive strategies including devices and functional surgery are available to manage such complications. In spite of undisputable improvements during the last decades, many patients remain significantly disabled, and a fully satisfying management of l-dopa-induced motor complications is still an important unmet need of PD therapy. This article reviews the recent trial results published from 2013 to April 2015 about pharmacological and nonpharmacological interventions to treat motor complications. Randomized controlled trials conducted in patients suffering from already established complications showed that new levodopa (l-dopa) formulations such as intrajejunal l-dopa-carbidopa infusion and bilayered extended-release l-dopa-carbidopa (IPX066) can improve motor fluctuations. Positive results were also obtained with a new monoamine oxidase B (MAO-B) inhibitor (safinamide) and a catechol-O-methyltransferase COMT inhibitor (opicapone). Pilot data suggest that new formulations of dopamine agonists (inhaled apomorphine) are also of potential interest. The development of novel nondopaminergic adenosine A2A antagonists (istradefylline, preladenant, and tozadenant) to treat motor fluctuations showed conflicting results in phase 2 and phase 3 trials. For dyskinesia, trials with new amantadine extended-release formulations confirmed the interest of the glutamatergic N-methyl-d-aspartate (NMDA) antagonist approach. Positive pilot antidyskinetic effects were also recently reported using serotonin agents such as eltoprazine and glutamate mGluR5 modulators such as mavoglurant. However, the translation to clinical practice of such innovative concepts remains challenging, because subsequent phase 2 trials conducted to confirm the antidyskynetic effects of mavoglurant failed, leading to the interruption of the development of this compound for this indication.

Olfactory Dysfunction Evaluation Is Not Affected by Comorbid Depression in Parkinson's Disease.

BACKGROUND: Olfactory function assessment is an important screening tool for Parkinson's disease (PD) diagnosis. It is debated whether olfaction is affected by comorbid depression. We assessed the relationship between depression and olfaction in PD and determined whether depression may limit the usefulness of olfactory testing for PD diagnosis. METHODS: Olfaction was evaluated using the Sniffin' Sticks test and the Hyposmia Rating Scale in four groups of subjects: PD patients without depression (n = 30); PD patients with major depression (PDD; n = 30); major depressive disorder (MDD) patients (n = 29); and healthy controls (HCs; n = 30). RESULTS: No differences were found between PD and PDD patients for total Sniffin' Sticks test, threshold, discrimination or identification scores, or in Hyposmia Rating Scale, although both groups differed from HCs and MDD patients (P < 0.05), which, in turn, showed similar olfactory scores. CONCLUSIONS: Lack of differences in olfactory impairment between PD and PDD suggest that depression may not contribute to olfactory dysfunction in PD.

Falls in ambulatory non-demented patients with Parkinson's disease.

This study aimed at determining the prevalence of falling in PD patients, to assess generic and disease-specific clinical and pharmacological factors, relationship with health-related quality of life (HR-QoL) and changes in falls from OFF to ON in patients with motor fluctuations. Six-hundred and eighty-three PD patients of the COPARK survey were evaluated (11 had missing data and were excluded from the analysis). Patients with falls were identified as those with a UPDRS Item 13 ≥ 1 in the ON condition. All patients were assessed in a standardized manner [demographics, treatments, Unified PD Rating Scale (UPDRS), Hospital Anxiety and Depression Scale, Pittsburg questionnaire and HR-QoL scales (SF36, PDQ39)]. Falling was reported by 108/672 (16%) PD patients during the ON state and prevalence increased according to PD severity, from 5% in Hoehn and Yahr stage 1-60% in stage 4. Falling was significantly related to lower HR-QoL. Falling correlated with (1) generic factors such as female gender, age at the end of academic studies and diuretics consumption, (2) motor PD-specific factors including disease severity, frozen gait, difficulties when arising from a chair, dyskinesia and higher levodopa daily equivalent dose and (3) non-motor PD-specific factors such as orthostatic hypotension and hallucinations. Falling was more frequent in OFF than in ON in 48/74 (64%) patients with motor fluctuations and remained unchanged in 27 patients (36%). In summary, falling affected a significant proportion of PD patients, especially in advanced stages. It was associated with a variety of generic and PD-specific factors and was related to reduced HR-QoL.

Trends in inpatient antiparkinson drug use in the USA, 2001-2012.

PURPOSE: Although therapeutic options and clinical guidelines for Parkinson's disease (PD) have changed significantly in the past 15 years, prescribing trends in the USA remain unknown. The purpose of this population-based cohort study was to examine patterns of inpatient antiparkinson drug use between January 2001 and December 2012 in relation to clinical guideline publication, drug introduction/withdrawal, and emerging safety concerns. METHODS: A total of 16,785 inpatients receiving pharmacological treatment for PD were identified in the Cerner Health Facts database. Our primary outcome was standardized (age, sex, race, and census region) annual prevalence of antiparkinson drug use. We also examined antiparkinson medication trends and polypharmacy by age and sex. RESULTS: The most frequently prescribed antiparkinson drugs between 2001 and 2012 were levodopa (85%) and dopamine agonists (28%). Dopamine agonist use began declining in 2007, from 34 to 27% in 2012. The decline followed publication of the American Academy of Neurology's practice parameter refuting levodopa toxicity, pergolide withdrawal, and pramipexole label revisions. Despite safety concerns for cognitive impairment and falls, individuals ≥80 years of age demonstrated stable rates of dopamine agonist use from 2001 to 2012. Polypharmacy was most common in younger patients. CONCLUSIONS: Dopamine agonist use declined from 2007 to 2012, suggesting that increased awareness of safety issues and practice guidelines influenced prescribing. These events appear to have minimally influenced treatment provided to older PD patients. Antiparkinson prescribing trends indicate that safety and best practice information may be communicated effectively.

Effects of different "relaxing" music styles on the autonomic nervous system.

The objective of this study was to assess the effects on heart rate variability (HRV) of exposure to different styles of "relaxing" music. Autonomic responses to musical stimuli were correlated with subjective preferences regarding the relaxing properties of each music style. Linear and nonlinear HRV analysis was conducted in 25 healthy subjects exposed to silence or to classical, new age or romantic melodies in a random fashion. At the end of the study, subjects were asked to choose the melody that they would use to relax. The low-to-high-frequency ratio was significantly higher when subjects were exposed to "new age" music when compared with silence (3.4 ± 0.3 vs. 2.6 ± 0.3, respectively, P < 0.02), while no differences were found with "classical" or "romantic" melodies (2.1 ± 0.4 and 2.2 ± 0.3). These results were related to a reduction in the high frequency component with "new age" compared to silence (17.4 ± 1.9 vs. 23.1 ± 1.1, respectively P < 0.004). Significant differences across melodies were also found for nonlinear HRV indexes. Subjects' preferences did not correlate with autonomic responses to melodies. The results suggest that "new age" music induced a shift in HRV from higher to lower frequencies, independently on the music preference of the listener.

Emerging drugs for autonomic dysfunction in Parkinson's disease.

INTRODUCTION: Autonomic dysfunction, including orthostatic hypotension (OH), sialorrhea, sexual dysfunction, urinary dysfunction and constipation is a common feature of Parkinson's disease (PD). Even though its treatment has been recognized as a major unmet need in PD, there is a paucity of clinical trials to assess their treatment. AREAS COVERED: Evidence about the efficacy and safety of available treatments for autonomic dysfunction is summarized. Potential targets for upcoming therapies are then discussed in light of what is currently known about the physiopathology of each disorder in PD. Proof-of-concept trials and circumstantial evidence about treatments for autonomic dysfunction as well as upcoming clinical trials are discussed. Finally, critical aspects of clinical trials design are considered. EXPERT OPINION: Botulinum toxin (BTX) or glycopyrrolate might be used for sialorrhea whereas macrogol could be useful in constipation. There is preliminary evidence suggesting that fludrocortisone, domperidone, droxidopa or fipamezole may be effective for the treatment of OH. Tropicamide, clonidine or radiotherapy are under development for sialorrhea. Sildenafil may be effective for the treatment of erectile dysfunction; BTX or behavioral therapy for urinary incontinence and lubiprostone and probiotics for constipation. Sound clinical trials are needed in order to allow firm evidence-based recommendations about these treatments.

Screen use, sleep duration, daytime somnolence, and academic failure in school-aged adolescents.

In this study, we examined the relationship between screen time use, sleep characteristics, daytime somnolence, and academic performance in school-aged adolescents. We surveyed 1,257 12- to 18-year-old adolescents attending 52 schools in urban or suburban areas of Argentina. We recorded the daily exposure to various screen-based activities, including video- and online-gaming, social media, TV or streaming. Screen time and device type in the hour before bedtime, sleep patterns during weekdays and weekends, somnolence (Pediatric Daytime Sleepiness Scale score), and grades in language and mathematics were also assessed. Structural Equation Modelling was used to identify a path connecting the latent variables. Results are expressed as standardized regression weights (srw). Missing data were present in 393 subjects, and thus the final sample consisted of 864 complete responses. Daytime somnolence (i.e., PDSS score ≥ 15) was observed in 614 participants (71%), and academic failure (i.e., grades < 7/10) in 352 of them (41%). Time spent using video gaming consoles was negatively associated with sleep duration (srw = -0.22, p<0.01) and positively connected with daytime somnolence (srw = 0.11, p<0.01). Use of mobile devices was associated with lower academic performance (srw = -0.11, p<0.01). Sleep duration was inversely related to daytime somnolence (srw = -0.27, p<0.01), which was in turn negatively associated with academic performance (srw = -0.18, p<0.05). Bedtime computer use did not influence any outcome. In summary, among adolescents, screen use adversely affected nighttime sleep, daytime somnolence, and academic performance. These findings call for the implementation of educational public campaigns aimed at promoting healthy sleep and reducing screen exposure among adolescents.

The Genetic Basis of Probable REM Sleep Behavior Disorder in Parkinson's Disease.

Patients with Parkinson's Disease (PD) experience REM sleep behavior disorder (RBD) more frequently than healthy controls. RBD is associated with torpid disease evolution. To test the hypothesis that differential genetic signatures might contribute to the torpid disease evolution in PD patients with RBD we compared the rate of genetic mutations in PD patients with or without probable RBD. Patients with a clinical diagnosis of PD in the Parkinson's Progression Markers Initiative (PPMI) database entered the study. We excluded those with missing data, dementia, psychiatric conditions, or a diagnosis change over the first five years from the initial PD diagnosis. Probable RBD (pRBD) was confirmed by a REM Sleep Behavior Disorder Screening Questionnaire score > 5 points. Logistic regression and Machine Learning (ML) algorithms were used to relate Single Nucleotide Polymorphism (SNPs) in PD-related genes with pRBD. We included 330 PD patients fulfilling all inclusion and exclusion criteria. The final logistic multivariate model revealed that the following SNPs increased the risk of pRBD: GBA_N370S_rs76763715 (OR, 95% CI: 3.38, 1.45-7.93), SNCA_A53T_rs104893877 (8.21, 2.26-36.34), ANK2. CAMK2D_rs78738012 (2.12, 1.08-4.10), and ZNF184_rs9468199 (1.89, 1.08-3.33). Conversely, SNP COQ7. SYT17_rs11343 reduced pRBD risk (0.36, 0.15-0.78). The ML algorithms led to similar results. The predictive models were highly specific (95-99%) but lacked sensitivity (9-39%). We found a distinctive genetic signature for pRBD in PD. The high specificity and low sensitivity of the predictive models suggest that genetic mutations are necessary but not sufficient to develop pRBD in PD. Additional investigations are needed.