Penetrance estimate of LRRK2 p.G2019S mutation in individuals of non-Ashkenazi Jewish ancestry

ABSTRACT

Background

Penetrance estimates of the leucine-rich repeat kinase 2 (LRRK2) p.G2019S mutation for PD vary widely (24%-100%). The p.G2019S penetrance in individuals of Ashkenazi Jewish ancestry has been estimated as 25%, adjusted for multiple covariates. It is unknown whether penetrance varies among different ethnic groups. The objective of this study was to estimate the penetrance of p.G2019S in individuals of non-Ashkenazi Jewish ancestry and compare penetrance between Ashkenazi Jews and non-Ashkenazi Jews to age 80.

Methods

The kin-cohort method was used to estimate penetrance in 474 first-degree relatives of 69 non-Ashkenazi Jewish LRRK2 p.G2019S carrier probands at 8 sites from the Michael J. Fox LRRK2 Cohort Consortium. An identical validated family history interview was administered to assess age at onset of PD, current age, or age at death for relatives in different ethnic groups at each site. Neurological examination and LRRK2 genotype of relatives were included when available.

Results

Risk of PD in non-Ashkenazi Jewish relatives who carry a LRRK2 p.G2019S mutation was 42.5% (95% confidence interval [CI]: 26.3%-65.8%) to age 80, which is not significantly higher than the previously estimated 25% (95% CI: 16.7%-34.2%) in Ashkenazi Jewish carrier relatives. The penetrance of PD to age 80 in LRRK2 p.G2019S mutation carrier relatives was significantly higher than the noncarrier relatives, as seen in Ashkenazi Jewish relatives.

Conclusions

The similar penetrance of LRRK2 p.G2019S estimated in Ashkenazi Jewish carriers and non-Ashkenazi Jewish carriers confirms that p.G2019S penetrance is 25% to 42.5% at age 80 in all populations analyzed. 

Movement Disorders 2017

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

Abstract

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.

Movement Disorders 2017

Cutaneous nerve biomarkers in transthyretin familial amyloid polyneuropathy

Abstract

Objective

To determine the utility of skin biopsies as a biomarker of disease severity in subjects with amyloid neuropathy.

Methods

Five groups of patients were studied: (1) transthyretin (TTR) familial amyloidotic polyneuropathy (FAP; n = 20), (2) TTR mutation carriers without peripheral neuropathy (TTR-noPN; n = 10), (3) healthy controls (n = 20), (4) diabetic neuropathy disease controls (n = 20), and (5) patients with light-chain (AL) amyloid (n = 2). All subjects underwent neurological examination and 3mm skin biopsies. Sections were stained with anti-PGP9.5, anti-TTR, and Congo red. Intraepidermal (IENFD), sweat gland (SGNFD), and pilomotor nerve fiber densities (PMNFD) were measured. Correlations between the amount of amyloid present (amyloid burden), fiber subtype, and Neuropathy Impairment Score in the Lower Limbs (NIS-LL) were evaluated.

Results

IENFD, SGNFD, and PMNFD were all significantly reduced in TTR-FAP patients versus healthy controls, whereas TTR-noPN subjects had intermediate reductions. Lower nerve fiber densities were associated with NIS-LL (p < 0.001). Congo red staining revealed brilliant red amyloid deposits confirmed by apple-green birefringence within dermal collagen, sweat glands, and arrector pili that engulfed axons. The diagnostic sensitivity and specificity to detect amyloid in skin were 70% and 100%. Both AL amyloidosis and 2 of 10 TTR-noPN subjects were Congo red–positive. Amyloid burden correlated with IENFD (r = −0.63), SGNFD (r = −0.67), PMNFD (r = −0.50), and NIS-LL (r = −0.57). Wild-type TTR staining was less prominent in TTR-FAP patients.

Interpretation

Cutaneous amyloid was detected in 70% of TTR-FAP and 20% of TTR-noPN subjects. Amyloid burden correlated strongly with reductions in IENFD, SGNFD, PMNFD, and NIS-LL. Skin is an attractive tissue to establish an amyloid diagnosis, and amyloid burden has potential as a biomarker to detect treatment effect in TTR-FAP drug trials. 

Annals Of Neurology 2017

Brain Calcifications in Adult-Onset Genetic Leukoencephalopathies A Review

Abstract

Importance  Adult-onset genetic leukoencephalopathies and leukodystrophies are increasingly recognized as a heterogeneous group of disorders with new diagnostic approaches and potential treatments. In the new era of genomics, the challenging interpretation of individual genetic variations requires an accurate phenotypic description and classification. Clinical and magnetic resonance imaging (MRI)–based approaches have been proposed to improve the diagnostic process of adult-onset leukoencephalopathies. Cerebral calcifications, when associated with white matter hyperintensities, are of major importance in the decision-making process to focus the diagnosis among the diversity of rare causes.

Observations  This literature review demonstrated that the morphologic features and topography of the calcifications observed in a careful combined analysis of computed tomographic and MRI scans may help indicate the diagnosis of adult-onset genetic leukoencephalopathies. Vascular genetic leukoencephalopathies are an important cause of leukoencephalopathy with calcifications. Among them, COL4A1-related disorders are frequently associated with spotlike calcifications in the basal ganglia. Adult-onset leukoencephalopathy with axonal spheroids, a probably underestimated disorder, is associated with a specific pattern of calcifications: small, symmetric, sparing the basal ganglia, and a stepping stone appearance in the frontal pericallosal region. Moreover, disorders primarily associated with basal ganglia calcifications, such as primary familial brain calcifications, can be associated with marked leukoencephalopathy.

Conclusions and Relevance  The number of identified causes of adult-onset genetic leukoencephalopathies has recently increased. A diagnostic algorithm should take into account the pattern of calcifications to better target the genetic analyses.

JAMA Neurology 2017

Intensive Blood Pressure Reduction and Spot Sign in Intracerebral Hemorrhage

Abstract

Importance  The computed tomographic angiography (CTA) spot sign is associated with intracerebral hemorrhage (ICH) expansion and may mark those patients most likely to benefit from intensive blood pressure (BP) reduction.

Objective  To investigate whether the spot sign is associated with ICH expansion across a wide range of centers and whether intensive BP reduction decreases hematoma expansion and improves outcome in patients with ICH and a spot sign.

Design, Setting, and Participants  SCORE-IT (Spot Sign Score in Restricting ICH Growth) is a preplanned prospective observational study nested in the Antihypertensive Treatment of Acute Cerebral Hemorrhage II (ATACH-II) randomized clinical trial. Participants included consecutive patients with primary ICH who underwent a CTA within 8 hours from onset at 59 sites from May 15, 2011, through December 19, 2015. Data were analyzed for the present study from July 1 to August 31, 2016.

Main Outcomes and Measures  Patients in ATACH-II were randomized to intensive (systolic BP target, <140 mm Hg) vs standard (systolic BP target, <180 mm Hg) BP reduction within 4.5 hours from onset. Expansion of ICH was defined as hematoma growth of greater than 33%, and an unfavorable outcome was defined as a 90-day modified Rankin Scale score of 4 or greater (range, 0-6). The association among BP reduction, ICH expansion, and outcome was investigated with multivariable logistic regression.

Results  A total of 133 patients (83 men [62.4%] and 50 women [37.6%]; mean [SD] age, 61.9 [13.1] years) were included. Of these, 53 (39.8%) had a spot sign, and 24 of 123 without missing data (19.5%) experienced ICH expansion. The spot sign was associated with expansion with sensitivity of 0.54 (95% CI, 0.34-0.74) and specificity of 0.63 (95% CI, 0.53-0.72). After adjustment for potential confounders, intensive BP treatment was not associated with a significant reduction of ICH expansion (relative risk, 0.83; 95% CI, 0.27-2.51; P = .74) or improved outcome (relative risk of 90-day modified Rankin Scale score ≥4, 1.24; 95% CI, 0.53-2.91; P = .62) in spot sign–positive patients.

Conclusions and Relevance  The predictive performance of the spot sign for ICH expansion was lower than in prior reports from single-center studies. No evidence suggested that patients with ICH and a spot sign specifically benefit from intensive BP reduction.

Jama Neurology 2017

MCM3AP in recessive Charcot-Marie-Tooth neuropathy and mild intellectual disability

Abstract

Defects in mRNA export from the nucleus have been linked to various neurodegenerative disorders. We report mutations in the gene MCM3AP, encoding the germinal center associated nuclear protein (GANP), in nine affected individuals from five unrelated families. The variants were associated with severe childhood onset primarily axonal (four families) or demyelinating (one family) Charcot-Marie-Tooth neuropathy. Mild to moderate intellectual disability was present in seven of nine affected individuals. The affected individuals were either compound heterozygous or homozygous for different MCM3AP variants, which were predicted to cause depletion of GANP or affect conserved amino acids with likely importance for its function. Accordingly, fibroblasts of affected individuals from one family demonstrated severe depletion of GANP. GANP has been described to function as an mRNA export factor, and to suppress TDP-43-mediated motor neuron degeneration in flies. Thus our results suggest defective mRNA export from nucleus as a potential pathogenic mechanism of axonal degeneration in these patients. The identification of MCM3AP variants in affected individuals from multiple centres establishes it as a disease gene for childhood-onset recessively inherited Charcot-Marie-Tooth neuropathy with intellectual disability.

Brain 2017

Neuroprotection in stroke: the importance of collaboration and reproducibility

Abstract

Acute ischaemic stroke accounts for 6.5 million deaths per year, and by 2030 will result in the annual loss of over 200 million disability-adjusted life years globally. There have been considerable recent advances in the gold standard of acute ischaemic stroke treatment, some aspects of which—aspirin to prevent recurrence, and treating patients in specialized stroke wards—are widely applicable. Recanalization of the occluded artery through thrombolysis and/or endovascular thrombectomy is restricted to only a small proportion of patients, due to contra-indications and the costs associated with establishing the infrastructure to deliver these treatments. The use of neuroprotective agents in stroke has been a notable failure of translation from medical research into clinical practice. Yet, with the advent of endovascular thrombectomy and the ability to investigate patients in much greater detail through advanced imaging modalities, neuroprotective agents can and should be re-examined as adjunct therapies to recanalization. In parallel, this requires appropriate planning on behalf of the preclinical stroke research community: there is a need to reinvestigate these therapies in a more collaborative manner, to enhance reproducibility through reduced attrition, improved reporting, and adopting an approach to target validation that more closely mimics clinical trials. This review will describe some of the novel strategies being used in stroke research, and focus on a few key examples of neuroprotective agents that are showing newfound promise in preclinical models of stroke therapy. Our primary aim is to give an overview of some of the challenges faced by preclinical stroke research, and suggest potential ways to improve translational success.

Brain 2017

Anterior pallidal deep brain stimulation for Tourette's syndrome: a randomised, double-blind, controlled trial

Summary

Background

Deep brain stimulation (DBS) has been proposed to treat patients with severe Tourette's syndrome, and open-label trials and two small double-blind trials have tested DBS of the posterior and the anterior internal globus pallidus (aGPi). We aimed to specifically assess the efficacy of aGPi DBS for severe Tourette's syndrome.

Methods

In this randomised, double-blind, controlled trial, we recruited patients aged 18–60 years with severe and medically refractory Tourette's syndrome from eight hospitals specialised in movement disorders in France. Enrolled patients received surgery to implant bilateral electrodes for aGPi DBS; 3 months later they were randomly assigned (1:1 ratio with a block size of eight; computer-generated pairwise randomisation according to order of enrolment) to receive either active or sham stimulation for the subsequent 3 months in a double-blind fashion. All patients then received open-label active stimulation for the subsequent 6 months. Patients and clinicians assessing outcomes were masked to treatment allocation; an unmasked clinician was responsible for stimulation parameter programming, with intensity set below the side-effect threshold. The primary endpoint was difference in Yale Global Tic Severity Scale (YGTSS) score between the beginning and end of the 3 month double-blind period, as assessed with a Mann-Whitney-Wilcoxon test in all randomly allocated patients who received active or sham stimulation during the double-blind period. We assessed safety in all patients who were enrolled and received surgery for aGPi DBS. This trial is registered with ClinicalTrials.gov, number NCT00478842.

Findings

Between Dec 6, 2007, and Dec 13, 2012, we enrolled 19 patients. We randomly assigned 17 (89%) patients, with 16 completing blinded assessments (seven [44%] in the active stimulation group and nine [56%] in the sham stimulation group). We noted no significant difference in YGTSS score change between the beginning and the end of the 3 month double-blind period between groups (active group median YGTSS score 68·5 [IQR 34·0 to 83·5] at the beginning and 62·5 [51·5 to 72·0] at the end, median change 1·1% [IQR −23·9 to 38·1]; sham group 73·0 [69·0 to 79·0] and 79·0 [59·0 to 81·5], median change 0·0% [–10·6 to 4·8]; p=0·39). 15 serious adverse events (three in patients who withdrew before stimulation and six each in the active and sham stimulation groups) occurred in 13 patients (three who withdrew before randomisation, four in the active group, and six in the sham group), with infections in DBS hardware in four patients (two who withdrew before randomisation, one in the sham stimulation group, and one in the active stimulation group). Other serious adverse events included one electrode misplacement (active stimulation group), one episode of depressive signs (active stimulation group), and three episodes of increased tic severity and anxiety (two in the sham stimulation group and one in the active stimulation group).

Interpretation

3 months of aGPi DBS is insufficient to decrease tic severity for patients with Tourette's syndrome. Future research is needed to investigate the efficacy of aGPi DBS for patients over longer periods with optimal stimulation parameters and to identify potential predictors of the therapeutic response.

Lancet Neurology 2017

Prognostic factors for chronic headache A systematic review

ABSTRACT

Objective: To identify predictors of prognosis and trial outcomes in prospective studies of people with chronic headache.

Methods: This was a systematic review of published literature in peer-reviewed journals. We included (1) randomized controlled trials (RCTs) of interventions for chronic headache that reported subgroup analyses and (2) prospective cohort studies, published in English, since 1980. Participants included adults with chronic headache (including chronic headache, chronic migraine, and chronic tension-type headache with or without medication overuse headache). We searched key databases using free text and MeSH terms. Two reviewers independently extracted data and assessed the methodologic quality of studies and overall quality of evidence identified using appropriate published checklists.

Results: We identified 16,556 titles, removed 663 duplicates, and reviewed 199 articles, of which 27 were included in the review—17 prospective cohorts and 10 RCTs with subgroup analyses reported. There was moderate-quality evidence indicating that depression, anxiety, poor sleep and stress, medication overuse, and poor self-efficacy for managing headaches are potential prognostic factors for poor prognosis and unfavorable outcomes from preventive treatment in chronic headache. There was inconclusive evidence about treatment expectations, age, age at onset, body mass index, employment, and several headache features.

Conclusions: This review identified several potential predictors of poor prognosis and worse outcome postinterventions in people with chronic headache. The majority of these are modifiable. The findings also highlight the need for more longitudinal high-quality research of prognostic factors in chronic headache.

Neurology 2017

The evolving genetic risk for sporadic ALS

ABSTRACT

Objective: To estimate the genetic risk conferred by known amyotrophic lateral sclerosis (ALS)–associated genes to the pathogenesis of sporadic ALS (SALS) using variant allele frequencies combined with predicted variant pathogenicity.

Methods: Whole exome sequencing and repeat expansion PCR of C9orf72 and ATXN2 were performed on 87 patients of European ancestry with SALS seen at the University of Utah. DNA variants that change the protein coding sequence of 31 ALS-associated genes were annotated to determine which were rare and deleterious as predicted by MetaSVM. The percentage of patients with SALS with a rare and deleterious variant or repeat expansion in an ALS-associated gene was calculated. An odds ratio analysis was performed comparing the burden of ALS-associated genes in patients with SALS vs 324 normal controls.

Results: Nineteen rare nonsynonymous variants in an ALS-associated gene, 2 of which were found in 2 different individuals, were identified in 21 patients with SALS. Further, 5 deleterious C9orf72 and 2 ATXN2 repeat expansions were identified. A total of 17.2% of patients with SALS had a rare and deleterious variant or repeat expansion in an ALS-associated gene. The genetic burden of ALS-associated genes in patients with SALS as predicted by MetaSVM was significantly higher than in normal controls.

Conclusions: Previous analyses have identified SALS-predisposing variants only in terms of their rarity in normal control populations. By incorporating variant pathogenicity as well as variant frequency, we demonstrated that the genetic risk contributed by these genes for SALS is substantially lower than previous estimates.

Neurology 2017

Connectivity predicts deep brain stimulation outcome in Parkinson's disease

Abstract

Objective: The benefit of deep brain stimulation (DBS) for Parkinson's disease (PD) may depend on connectivity between the stimulation site and other brain regions, but which regions and whether connectivity can predict outcome in patients remains unknown. Here, we identify the structural and functional connectivity profile of effective DBS to the subthalamic nucleus (STN) and test its ability to predict outcome in an independent cohort.

Methods: A training dataset of 51 PD patients with STN DBS was combined with publicly available human connectome data (diffusion tractography and resting state functional connectivity) to identify connections reliably associated with clinical improvement (motor score of Unified Parkinson's Disease Rating Scale). This connectivity profile was then used to predict outcome in an independent cohort of 44 patients from a different center.

Results: In the training dataset, connectivity between the DBS electrode and a distributed network of brain regions correlated with clinical response including structural connectivity to supplementary motor area and functional anticorrelation to primary motor cortex (p < 0.001). This same connectivity profile predicted response in an independent patient cohort (p < 0.01). Structural and functional connectivity were independent predictors of clinical improvement (p < 0.001) and estimated response in individual patients with an average error of 15% UPDRS improvement. Results were similar using connectome data from normal subjects or a connectome age, sex, and disease-matched to our DBS patients.

Interpretation: Effective STN-DBS for PD is associated with a specific connectivity profile that can predict clinical outcome across independent cohorts. This prediction does not require specialized imaging in PD patients themselves. 

Annals of Neurology 2017

Epileptic networks in action: Synchrony between distant hemodynamic responses

ABSTRACT

Objective: Structural and functional imaging studies in focal epilepsy often reveal distributed regions of abnormality. These are interpreted as representing the existence of epileptic networks but the presence of actual neuronal interactions between these regions has not been demonstrated. We sought to determine if the distributed hemodynamic responses often seen in fMRI studies of scalp interictal epileptic discharges (IEDs) actually correspond to synchronized neuronal activities when examining the intracerebral EEG (iEEG) at distant nodes of the network.

Methods: We studied 28 patients who underwent first EEG-fMRI and then iEEG, and had significant hemodynamic responses in the gray matter. We co-registered the hemodynamic responses to the iEEG electrode contacts positions and analyzed synchrony, measured by correlation, between IEDs recorded by iEEG in regions with and without hemodynamic responses.

Results: The synchrony of intracerebral IED activity between pairs of regions showing a hemodynamic response was higher compared to that between pairs of regions without (p<0.0001) and between pairs of regions, one with and one without hemodynamic response (p<0.0001). These differences were found during the interictal periods with IEDs but were absent during the interictal periods without IEDs. Higher synchrony was also observed between regions involved at seizure-onset (p<0.0001).

Interpretation: EEG-fMRI studies are unique in their ability to reveal hemodynamic concomitants of IEDs anywhere in the brain. This study proves that iEEG activity is synchronized between these regions of hemodynamic response, thus demonstrating the existence of an actual neuronally-based interictal epileptic network. This also validates the EEG-fMRI approach to reveal this network non-invasively.

Annals of Neurology 2017

Cutaneous Nerve Biomarkers in Transthyretin Familial Amyloid Polyneuropathy

Abstract

Objective: Determine the utility of skin biopsies as a biomarker of disease severity in subjects with amyloid neuropathy.

Methods: Five groups of patients were studied 1) TTR-FAP (N=20), 2) TTR mutation carriers without neuropathy (TTR-noPN, N=10), 3) healthy controls (N=20), 4) diabetic neuropathy disease controls (N=20) and 5) patients with AL-amyloid (N=2). All subjects underwent neurological examination and 3mm skin biopsies. Sections were stained with anti-PGP9.5, anti-TTR and Congo red. Intraepidermal (IENFD), sweat gland (SGNFD) and pilomotor nerve fiber densities (PMNFD) were measured. Correlations between the amount of amyloid present (amyloid burden), fiber subtype and Neuropathy Impairment Score-LL (NIS-LL) were evaluated.

Results: IENFD, SGNFD, and PMNFD were all significantly reduced in TTR-FAP patients vs. healthy controls while TTR-noPN subjects had intermediate reductions. Lower nerve fiber densities were associated with NIS-LL (p<0.001). Congo red staining revealed brilliant-red amyloid deposits confirmed by apple-green birefringence within dermal collagen, sweat glands, and arrector pili that engulfed axons. The diagnostic sensitivity and specificity to detect amyloid in skin were 70% and 100%. Both AL and 2/10 TTR-noPN subjects were Congo red-positive. Amyloid burden correlated with IENFD (r=-0.63), SGNFD (r=-0.67), PMNFD (r=-0.50) and NIS-LL (r=-0.57). Wild-type TTR staining was less prominent in TTR-FAP patients.

Conclusion: Cutaneous amyloid was detected in 70% of TTR-FAP and 20% of TTR-noPN subjects. Amyloid burden correlated strongly with reductions in IENFD, SGNFD, PMNFD and NIS-LL. Skin is an attractive tissue to establish an amyloid diagnosis and amyloid burden has potential as a biomarker to detect treatment effect in TTR-FAP drug trials.

Annals of Neurology 2017

Autologous haematopoietic stem cell transplantation for treatment of multiple sclerosis

Autologous haematopoietic stem cell transplantation (AHSCT) is a multistep procedure that enables destruction of the immune system and its reconstitution from haematopoietic stem cells. Originally developed for the treatment of haematological malignancies, the procedure has been adapted for the treatment of severe immune-mediated disorders. Results from ~20 years of research make a compelling case for selective use of AHSCT in patients with highly active multiple sclerosis (MS), and for controlled trials. Immunological studies support the notion that AHSCT causes qualitative immune resetting, and have provided insight into the mechanisms that might underlie the powerful treatment effects that last well beyond recovery of immune cell numbers. Indeed, studies have demonstrated that AHSCT can entirely suppress MS disease activity for 4–5 years in 70–80% of patients, a rate that is higher than those achieved with any other therapies for MS. Treatment-related mortality, which was 3.6% in studies before 2005, has decreased to 0.3% in studies since 2005. Current evidence indicates that the patients who are most likely to benefit from and tolerate AHSCT are young, ambulatory and have inflammatory MS activity. Clinical trials are required to rigorously test the efficacy, safety and cost-effectiveness of AHSCT against highly active MS drugs.

Nature Reviews Neurology 2017

Imaging and fluid biomarkers in frontotemporal dementia

Abstract

• Abstract• 
• References• 
• Author information

Frontotemporal dementia (FTD), the second most common type of presenile dementia, is a heterogeneous neurodegenerative disease characterized by progressive behavioural and/or language problems, and includes a range of clinical, genetic and pathological subtypes. The diagnostic process is hampered by this heterogeneity, and correct diagnosis is becoming increasingly important to enable future clinical trials of disease-modifying treatments. Reliable biomarkers will enable us to better discriminate between FTD and other forms of dementia and to predict disease progression in the clinical setting. Given that different underlying pathologies probably require specific pharmacological interventions, robust biomarkers are essential for the selection of patients with specific FTD subtypes. This Review emphasizes the increasing availability and potential applications of structural and functional imaging biomarkers, and cerebrospinal fluid and blood fluid biomarkers in sporadic and genetic FTD. The relevance of new MRI modalities — such as voxel-based morphometry, diffusion tensor imaging and arterial spin labelling — in the early stages of FTD is discussed, together with the ability of these modalities to classify FTD subtypes. We highlight promising new fluid biomarkers for staging and monitoring of FTD, and underline the importance of large, multicentre studies of individuals with presymptomatic FTD. Harmonization in the collection and analysis of data across different centres is crucial for the implementation of new biomarkers in clinical practice, and will become a great challenge in the next few years.

Nature Reviews Neurology 2017

ADS-5102 (Amantadine) Extended-Release Capsules for Levodopa-Induced Dyskinesia in Parkinson Disease (EASE LID Study) A Randomized Clinical Trial

Abstract

Importance  Medical treatment of levodopa-induced dyskinesia (LID) in Parkinson disease (PD) is an unmet need.

Objective  To evaluate the efficacy and safety of ADS-5102 (amantadine) extended-release 274-mg capsules for treatment of LID in patients with PD.

Design, Setting, and Participants  A randomized, double-blind, placebo-controlled clinical trial was conducted between May 7, 2014, and July 22, 2015, at 44 North American sites among patients with PD treated with levodopa who experienced at least 1 hour of troublesome dyskinesia per day with at least mild functional impact.

Interventions  Patients were randomized to receive placebo or 274 mg of ADS-5102 administered orally at bedtime for up to 25 weeks.

Main Outcomes and Measures  The primary efficacy analysis was the change from baseline to week 12 in the Unified Dyskinesia Rating Scale total score for ADS-5102 vs placebo in the modified intent-to-treat population. OFF time (amount of time the PD medication is not controlling motor symptoms) was a key secondary end point. Safety analyses included all patients who received the study drug (ADS-5102 or placebo).

Results  A total of 189 patients were screened, and 126 were randomized; the modified intent-to-treat population included 121 patients (51 women and 70 men; mean [SD] age, 64.7 [9.1] years). At week 12, the least-squares mean (SE) change in the Unified Dyskinesia Rating Scale score was –15.9 (1.6) for ADS-5102 (n = 63) and –8.0 (1.6) for placebo (n = 58) (treatment difference, –7.9; 95% CI, –12.5 to –3.3; P < .001). OFF time decreased by a mean (SE) of 0.6 (0.3) hours for ADS-5102 and increased by 0.3 (0.3) hours for placebo (treatment difference, –0.9 hours; 95% CI, –1.6 to –0.2; P = .02). Common adverse events for ADS-5102 vs placebo included visual hallucinations (15 [23.8%] vs 1 [1.7%]), peripheral edema (15 [23.8%] vs 0), and dizziness (14 [22.2%] vs 0). Adverse events led to treatment discontinuation for 13 patients receiving ADS-5102 (20.6%) vs 4 patients receiving placebo (6.9%).

Conclusions and Relevance  ADS-5102, 274 mg at bedtime, may be an effective treatment for LID. An additional benefit is reduced OFF time. To our knowledge, this is the first demonstration of an oral treatment reducing both LID and OFF time in patients with PD with dyskinesia.

Trial Registration  clinicaltrials.gov Identifier: NCT02136914

JAMA Neurology 2017