International Genetic Testing and Counseling Practices for Parkinson's Disease.

BACKGROUND: There is growing clinical and research utilization of genetic testing in Parkinson's disease (PD), including direct-to-consumer testing. OBJECTIVES: The aim is to determine the international landscape of genetic testing in PD to inform future worldwide recommendations. METHODS: A web-based survey assessing current practices, concerns, and barriers to genetic testing and counseling was administered to the International Parkinson and Movement Disorders Society membership. RESULTS: Common hurdles across sites included cost and access to genetic testing, and counseling, as well as education on genetic counseling. Region-dependent differences in access to and availability of testing and counseling were most notable in Africa. High-income countries also demonstrated heterogeneity, with European nations more likely to have genetic testing covered through insurance than Pan-American and Asian countries. CONCLUSIONS: This survey highlights not only diversity of barriers in different regions but also the shared and highly actionable needs for improved education and access to genetic counseling and testing for PD worldwide. © 2023 International Parkinson and Movement Disorder Society.

Tolerability of clobazam as add-on therapy in patients aged 50 years and older with drug-resistant epilepsy.

OBJECTIVE: To evaluate the tolerability of clobazam in patients with drug-resistant epilepsy aged 50 years and older. METHODS: We performed a single center, retrospective chart review of patients at least 50 years of age with drug resistant epilepsy of any type who started clobazam as an add on therapy. Retention rate, safety, and tolerability at 6 and 12 months and last follow-up, and the discontinuation rate due to side effects were analyzed. RESULTS: A total of 26 patients met inclusion criteria. Mean age was 62 ± 7.1 years, and 69.2% of patients were female. The mean baseline seizure frequency before initiation of clobazam was 2 (range 1-30) seizures per month. The mean total daily dose of clobazam administered was 13 (range 5 to 30) mg/day. At the 12-month follow-up visit after clobazam initiation, 40% of patients were seizure-free and an additional 45% of patients had > 50% reduction in seizure frequency. The mean seizure frequency at 12-month follow-up was 1.5 (range 0-24) seizures per month. The mean total dose of clobazam at 12-month follow-up was 14.25 (range 5 to 25) mg/day. The mean duration of clobazam at last follow was 55.2 ± 27.02 (mean ± SD months) and 18 (69.2%) patients remained on clobazam. Twenty out of 26 (76.9%) patients reported at least one side effect and 6/26 (23%) discontinued the medication within a month of initiation. At last follow-up, 40% remained seizure free on stable dosing. CONCLUSION: Clobazam can be a safe and tolerable, add-on treatment older adults with drug-resistant epilepsy. Those who responded tolerated the medication well. Discontinuation due to side effects occurred soon after initiation of therapy.

Co-Designing Digital Technologies for Improving Clinical Care in People with Parkinson's Disease: What Did We Learn?

The healthcare model is shifting towards integrated care approaches. This new model requires patients to be more closely involved. The iCARE-PD project aims to address this need by developing a technology-enabled, home-based, and community-centered integrated care paradigm. A central part of this project is the codesign process of the model of care, exemplified by the active participation of patients in the design and iterative evaluation of three sensor-based technological solutions. We proposed a codesign methodology used for testing the usability and acceptability of these digital technologies and present initial results for one of them, MooVeo. Our results show the usefulness of this approach in testing the usability and acceptability as well as the opportunity to incorporate patients' feedback into the development. This initiative will hopefully help other groups incorporate a similar codesign approach and develop tools that are well adapted to patients' and care teams' needs.

Genomewide Association Studies of LRRK2 Modifiers of Parkinson's Disease.

OBJECTIVE: The aim of this study was to search for genes/variants that modify the effect of LRRK2 mutations in terms of penetrance and age-at-onset of Parkinson's disease. METHODS: We performed the first genomewide association study of penetrance and age-at-onset of Parkinson's disease in LRRK2 mutation carriers (776 cases and 1,103 non-cases at their last evaluation). Cox proportional hazard models and linear mixed models were used to identify modifiers of penetrance and age-at-onset of LRRK2 mutations, respectively. We also investigated whether a polygenic risk score derived from a published genomewide association study of Parkinson's disease was able to explain variability in penetrance and age-at-onset in LRRK2 mutation carriers. RESULTS: A variant located in the intronic region of CORO1C on chromosome 12 (rs77395454; p value = 2.5E-08, beta = 1.27, SE = 0.23, risk allele: C) met genomewide significance for the penetrance model. Co-immunoprecipitation analyses of LRRK2 and CORO1C supported an interaction between these 2 proteins. A region on chromosome 3, within a previously reported linkage peak for Parkinson's disease susceptibility, showed suggestive associations in both models (penetrance top variant: p value = 1.1E-07; age-at-onset top variant: p value = 9.3E-07). A polygenic risk score derived from publicly available Parkinson's disease summary statistics was a significant predictor of penetrance, but not of age-at-onset. INTERPRETATION: This study suggests that variants within or near CORO1C may modify the penetrance of LRRK2 mutations. In addition, common Parkinson's disease associated variants collectively increase the penetrance of LRRK2 mutations. ANN NEUROL 2021;90:82-94.

Sleep disturbance in movement disorders: insights, treatments and challenges.

Sleep and circadian rhythm disturbances are central features of many movement disorders, exacerbating motor and non-motor symptoms and impairing quality of life. Understanding these disturbances to sleep is clinically important and may further our understanding of the underlying movement disorder. This review evaluates the current anatomical and neurochemical understanding of normal sleep and the recognised primary sleep disorders. In addition, we undertook a systematic review of the evidence for disruption to sleep across multiple movement disorders. Rapid eye movement sleep behaviour disorder has emerged as the most reliable prodromal biomarker for the alpha synucleinopathies, including Parkinson's disease and multiple system atrophy, often preceding motor symptom onset by several years. Abnormal sleep has also been described for many other movement disorders, but further evidence is needed to determine whether this is a primary or secondary phenotypic component of the underlying condition. Medication used in the treatment of motor symptoms also affects sleep and can aggravate or cause certain sleep disorders. Within the context of movement disorders, there is also some suggestion of a shared underlying mechanism for motor and sleep pathophysiology, with evidence implicating thalamic and brainstem structures and monoaminergic neurotransmission. This review highlights the need for an understanding of normal and abnormal sleep within the movement disorder clinic, an ability to screen for specific causes of poor sleep and to treat sleep disturbance to improve quality of life. Key sleep disorders also act as important biomarkers and have implications in diagnosis, prognosis and the development of future therapies.

Neurophysiological correlates of dual tasking in people with Parkinson's disease and freezing of gait.

Freezing of gait in people with Parkinson's disease (PwP) is associated with executive dysfunction and motor preparation deficits. We have recently shown that electrophysiological markers of motor preparation, rather than decision-making, differentiate PwP with freezing of gait (FOG +) and without (FOG -) while sitting. To examine the effect of locomotion on these results, we measured behavioural and electrophysiological responses in PwP with and without FOG during a target response time task while sitting (single-task) and stepping-in-place (dual-task). Behavioural and electroencephalographic data were acquired from 18 PwP (eight FOG +) and seven young controls performing the task while sitting and stepping-in-place. FOG + had slower response times while stepping compared with sitting. However, response times were significantly faster while stepping compared with sitting for controls. Electrophysiological responses showed no difference in decision-making potentials (centroparietal positivity) between groups or conditions but there were differences in neurophysiological markers of response inhibition (N2) and motor preparation (lateralized readiness potential, LRP) in FOG + while performing a dual-task. This suggests that the addition of a second complex motor task (stepping-in-place) impacts automatic allocation of resources in FOG +, resulting in delayed response times. The impact of locomotion on the generation of the N2 and LRP potentials, particularly in freezers, indirectly implies that these functions compete with locomotion for resources. In the setting of multiple complex tasks or cognitive impairment, severe motor dysfunction may result, leading to freezing of gait.

A Rare Case of Cecal Bascule in a Child With Normal Neurodevelopment.

Cecal volvulus is a rare cause of bowel obstruction in adults and an extremely rare presentation in children. One form known as a cecal bascule has only previously been reported in children with neurodevelopmental issues or with severe chronic constipation. We present the case of a 10-year-old boy who presented with an acute history of left lower quadrant abdominal pain, who upon investigation was found to have a cecal bascule.

Cognitive Indicators of Preclinical Behavioral Variant Frontotemporal Dementia in MAPT Carriers.

OBJECTIVES: The cognitive indicators of preclinical behavioral variant Frontotemporal Dementia (bvFTD) have not been identified. To investigate these indicators, we compared cross-sectional performance on a range of cognitive measures in 12 carriers of pathogenic MAPT mutations not meeting diagnostic criteria for bvFTD (i.e., preclinical) versus 32 demographically-matched familial non-carriers (n = 44). Studying preclinical carriers offers a rare glimpse into emergent disease, environmentally and genetically contextualized through comparison to familial controls. METHODS: Evaluating personnel blinded to carrier status administered a standardized neuropsychological battery assessing attention, speed, executive function, language, memory, spatial ability, and social cognition. Results from mixed effect modeling were corrected for multiplicity of comparison by the false discovery rate method, and results were considered significant at p < .05. To control for potential interfamilial variation arising from enrollment of six families, family was treated as a random effect, while carrier status, age, gender, and education were treated as fixed effects. RESULTS: Group differences were detected in 17 of 31 cognitive scores and spanned all domains except spatial ability. As hypothesized, carriers performed worse on specific measures of executive function, and social cognition, but also on measures of attention, speed, semantic processing, and memory storage and retrieval. CONCLUSIONS: Most notably, group differences arose on measures of memory storage, challenging long-standing ideas about the absence of amnestic features on neuropsychological testing in early bvFTD. Current findings provide important and clinically relevant information about specific measures that may be sensitive to early bvFTD, and advance understanding of neurocognitive changes that occur early in the disease. (JINS, 2019, 25, 184-194).

Complexity based measures of postural stability provide novel evidence of functional decline in fragile X premutation carriers.

BACKGROUND: Fragile X Associated Tremor/Ataxia Syndrome (FXTAS) is a neurodegenerative movement disorder characterized by tremor, ataxic gait, and balance issues resulting from a premutation of the Fragile X Mental Retardation 1 (FMR1) gene. No biomarkers have yet been identified to allow early diagnosis of FXTAS, however, recent studies have reported subtle issues in the stability of younger premutation carriers, before disease onset. This study investigates the efficacy of multiscale entropy analysis (MSE) in detecting early changes in the motor system of premutation carriers without FXTAS. METHODS: Sway complexity of 12 female Premutation carriers and 15 healthy Controls were measured under four conditions: eyes open, closed, and two dual-task conditions. A Sustained Attention Response Task (SART) and a working memory based N-Back task were employed to increase cognitive load while standing on the forceplate. A Complexity Index (Ci) was calculated for anterior-posterior (AP) and mediolateral (ML) sway. Independent t-tests were used to assess between-group differences and Oneway repeated measures ANOVA were used to assess within group differences with Bonferroni corrections to adjust for multiple comparisons. RESULTS: Group performances were comparable with eyes open and closed conditions. The Carrier group's Ci was consistent across tasks and conditions while the Control group's AP Ci increased significantly during the cognitive dual-task (p = 0.001). There was also a strong correlation between CGG repeat length and complexity for the Carrier group (p = 0.004). SIGNIFICANCE: Increased sway complexity is believed to stem from reallocation of attention to facilitate the increased cognitive demands of dual-tasks. Carriers' complexity did not change during dual-tasks, possibly indicating capacity interference and inefficient division of attention. Lower sway complexity in carriers suggests diminished adaptive capacity under stress as well as degradation of motor functioning. Therefore, sway complexity may be a useful tool in identifying early functional decline in FMR1 premutation carriers as well as monitoring progression towards disease onset.

Improving Resident Well-Being During Shiftwork: Are Casino Shifts the Answer?

PURPOSE: The objective of this study is to quantitatively evaluate the well-being of residents doing casino shifts compared with those doing standard overnight shifts while working in an academic pediatric emergency department. METHODS: A randomized prospective survey study was performed over a period of 1 year on all residents who were scheduled to complete a 28-day block. Each block (28-day period) within the year was designated as either a "standard" or "casino" block. The standard overnight shifts were scheduled from midnight to 0800 hours, and casino shifts occurred from either 2000 to 0400 hours (casino A) and 0400 to 1200 hours (casino B). Participating residents were asked to complete both a preblock and postblock survey. The primary outcome was defined as differences in resident well-being as assessed by the brief resident wellness profile (BRWP). A mood faces graphical rating item to assess overall mood was used as a secondary outcome measures as well as a 10-item survey based on World Health Organization domains for quality of life and adapted to reflect completion of shiftwork. RESULTS: A total of 124 (90%) of 138 residents completed the study and were included in the analysis. No significant difference in resident well-being measured by BRWP between those in the standard and casino shift groups (17 ± 2.5 for preblock standard and 16.9 ± 2.8 for casino, P = 0.904; 17.1 ± 2.7 for postblock standard and 17.2 ± 3.1 for casino, P = 0.817), or in the relative change of the BRWP preblock and postblock between the 2 groups (standard, 0.35 ± 2.7; casino, 0.29 ± 3.0; P = 0.926). No significant difference in the mood faces rating scale scores or the 10-item postblock survey was found. CONCLUSIONS: In the first study examining the effects of casino shifts on trainees, we found no effect of standard overnight versus casino shifts on their well-being. This counters the benefits previously seen in emergency department consultant staff and highlights the need for more studies specifically in trainees.