A review of disease progression models of Parkinson's disease and applications in clinical trials

Quantitative disease progression models for neurodegenerative disorders are gaining recognition as important tools for drug development and evaluation. In Parkinson's disease (PD), several models have described longitudinal changes in the Unified Parkinson's Disease Rating Scale (UPDRS), one of the most utilized outcome measures for PD trials assessing disease progression. We conducted a literature review to examine the methods and applications of quantitative disease progression modeling for PD using a combination of key words including “Parkinson disease,” “progression,” and “model.” For this review, we focused on models of PD progression quantifying changes in the total UPDRS scores against time. Four different models reporting equations and parameters have been published using linear and nonlinear functions. The reasons for constructing disease progression models of PD thus far have been to quantify disease trajectories of PD patients in active and inactive treatment arms of clinical trials, to quantify and discern symptomatic and disease-modifying treatment effects, and to demonstrate how model-based methods may be used to design clinical trials. The historical lack of efficiency of PD clinical trials begs for model-based simulations in planning for studies that result in more informative conclusions, particularly around disease modification.

Movement Disorders 2016

Prognostication of long-term outcomes after subarachnoid hemorrhage: The FRESH score

Objective

To create a multidimensional tool to prognosticate long-term functional, cognitive, and quality of life outcomes after spontaneous subarachnoid hemorrhage (SAH) using data up to 48 hours after admission.

Methods

Data were prospectively collected for 1,619 consecutive patients enrolled in the SAH outcome project July 1996 to March 2014. Linear models (LMs) were applied to identify factors associated with outcome in 1,526 patients with complete data. Twelve-month functional, cognitive, and quality of life outcomes were measured using the modified Rankin scale (mRS), Telephone Interview for Cognitive Status, and Sickness Impact Profile. Based on the LM residuals, we constructed the FRESH score (Functional Recovery Expected after Subarachnoid Hemorrhage). Score performance, discrimination, and internal validity were tested using the area under the receiver operating characteristic curve (AUC), Nagelkerke and Cox/Snell R², and bootstrapping. For external validation, we used a control population of SAH patients from the CONSCIOUS-1 study (n = 413).

Results

The FRESH score was composed of Hunt & Hess and APACHE-II physiologic scores on admission, age, and aneurysmal rebleed within 48 hours. Separate scores to prognosticate 1-year cognition (FRESH-cog) and quality of life (FRESH-quol) were developed controlling for education and premorbid disability. Poor functional outcome (mRS = 4–6) for score levels 1 through 9 respectively was present in 3, 6, 12, 38, 61, 83, 92, 98, and 100% at 1-year follow-up. Performance of FRESH (AUC = 0.90), FRESH-cog (AUC = 0.80), and FRESH-quol (AUC = 0.78) was high. External validation of our cohort using mRS as endpoint showed satisfactory results (AUC = 0.77). To allow for convenient score calculation, we built a smartphone app available for free download.

Interpretation

FRESH is the first clinical tool to prognosticate long-term outcome after spontaneous SAH in a multidimensional manner. Ann Neurol 2016

Diagnosis and etiology of congenital muscular dystrophy: We are halfway there

Objective

To evaluate the diagnostic outcomes in a large cohort of congenital muscular dystrophy (CMD) patients using traditional and next generation sequencing (NGS) technologies.

Methods

A total of 123 CMD patients were investigated using the traditional approaches of histology, immunohistochemical analysis of muscle biopsy, and candidate gene sequencing. Undiagnosed patients available for further testing were investigated using NGS.

Results

Muscle biopsy and immunohistochemical analysis found deficiencies of laminin α2, α-dystroglycan, or collagen VI in 50% of patients. Candidate gene sequencing and chromosomal microarray established a genetic diagnosis in 32% (39 of 123). Of 85 patients presenting in the past 20 years, 28 of 51 who lacked a confirmed genetic diagnosis (55%) consented to NGS studies, leading to confirmed diagnoses in a further 11 patients. Using the combination of approaches, a confirmed genetic diagnosis was achieved in 51% (43 of 85). The diagnoses within the cohort were heterogeneous. Forty-five of 59 probands with confirmed or probable diagnoses had variants in genes known to cause CMD (76%), and 11 of 59 (19%) had variants in genes associated with congenital myopathies, reflecting overlapping features of these conditions. One patient had a congenital myasthenic syndrome, and 2 had microdeletions. Within the cohort, 5 patients had variants in novel (PIGY and GMPPB) or recently published genes (GFPT1 and MICU1), and 7 had variants in TTN or RYR1, large genes that are technically difficult to Sanger sequence.

Interpretation

These data support NGS as a first-line tool for genetic evaluation of patients with a clinical phenotype suggestive of CMD, with muscle biopsy reserved as a second-tier investigation. 

Ann Neurol 2016

Skeletal muscle disorders of glycogenolysis and glycolysis

Skeletal muscle disorders of glycogenolysis and glycolysis account for most of the conditions collectively termed glycogen storage diseases (GSDs). These disorders are rare (incidence 1 in 20,000–43,000 live births), and are caused by autosomal or X-linked recessive mutations that result in a specific enzyme deficiency, leading to the inability to utilize muscle glycogen as an energy substrate. McArdle disease (GSD V) is the most common of these disorders, and is caused by mutations in the gene encoding muscle glycogen phosphorylase. Symptoms of McArdle disease and most other related GSDs include exercise intolerance, muscle contracture, acute rhabdomyolysis, and risk of acute renal failure. Older patients may exhibit muscle wasting and weakness involving the paraspinal muscles and shoulder girdle. For patients with these conditions, engaging with exercise is likely to be beneficial. Diagnosis is frequently delayed owing to the rarity of the conditions and lack of access to appropriate investigations. A few randomized clinical trials have been conducted, some focusing on dietary modification, although the quality of the evidence is low and no specific recommendations can yet be made. The development of EUROMAC, an international registry for these disorders, should improve our knowledge of their natural histories and provide a platform for future clinical trials.

JAMA Neurology 2016

Association of Blood Pressure, Blood Glucose, and Temperature With Neurological Outcome After Childhood Stroke

Importance  To our knowledge, no evidence-based guidelines are available for the best medical management of blood pressure, blood glucose levels, and temperature in pediatric patients after arterial ischemic stroke.

Objective  To determine the prevalence of abnormal blood pressure, blood glucose levels, and temperature in pediatric patients with acute arterial ischemic stroke and to explore any association between these measures and neurological outcome.

Design, Setting, and Participants  We performed a retrospective review of children aged 29 days to 18 years with their first arterial ischemic stroke between January 2009 and December 2013 at a tertiary academic children’s hospital. Ninety-eight children with stroke were identified by an International Classification of Diseases, Ninth Revision, code search and medical record review. Blood pressure, blood glucose, and temperature data were collected for 5 days after the stroke. Hypertension was defined as systolic blood pressure at or above the 95th percentile for age, sex, and height for 2 consecutive recordings and 2 consecutive days. Hypotension was defined as systolic and/or diastolic blood pressure below the fifth percentile for age, sex, and height for 2 consecutive recordings. Hyperglycemia was defined as a blood glucose level of 200 mg/dL or greater. Morbidity and mortality at 3 months were documented. Data analyses were performed from July 1, 2014, to December 31, 2015.

Interventions or Exposures  Abnormal blood pressure, blood glucose levels, and fever in the setting of arterial ischemic stroke.

Main Outcomes and Measures  The a priori outcome measure was poor clinical outcome, defined as a Pediatric Stroke Outcome Measure score of 1 or greater, which represents a moderate neurological deficit.

Results  The median (interquartile range) age of the 98 children was 6.0 (0.6-14.3) years, and 58 (59.2%) were male. Hypertension was present in 64 (65.3%), hypotension in 67 (68.4%), hyperglycemia in 17 (18.1%), and fever in 37 (37.8%). The strongest association with poor neurological outcome was an infarct size of 4% or greater of brain volume (odds ratio, 5.6; 95% CI, 2.0-15.4; P = .001). Hyperglycemia was also independently associated with poor neurological outcome (odds ratio, 3.9; 95% CI, 1.2-12.4; P = .02). Hypertension and fever were not significantly associated with infarct size, poor outcome, or death. Hypertension was not documented in 24 of 87 surviving children (27.6%) at 3-month follow-up and was not associated with poor neurological outcome.

Conclusions and Relevance  Abnormalities of blood pressure, blood glucose levels, and temperature are prevalent in children with arterial ischemic stroke. Infarct volume and hyperglycemia were associated with poor neurological outcome but hypertension and fever were not. Prospective studies that systematically record blood pressure, blood glucose, and temperature data are required to further assess the associations between these potentially modifiable physiological parameters and pediatric stroke outcome.

JAMA Neurology 2016

Combined-Modality Therapy With Radiation and Chemotherapy for Elderly Patients With Glioblastoma in the Temozolomide Era A National Cancer Database Analysis

Importance  The optimal management for elderly patients with glioblastoma (GBM) is controversial. Following maximal safe resection or biopsy, accepted treatment paradigms for elderly patients with GBM include combined-modality therapy (CMT) with both radiotherapy (RT) and chemotherapy (CT), RT alone, and CT alone.

Objective  To evaluate the overall survival (OS) outcomes associated with RT, CT, and CMT for elderly patients with GBM in the modern temozolomide era.

Design, Setting, and Participants  In this retrospective cohort study of a prospectively maintained, multi-institutional national cancer registry, the National Cancer Database was queried for elderly patients (≥65 years) with newly diagnosed GBM from January 1, 2005, through December 31, 2011, with complete data sets for RT, CT, tumor resection, Charlson-Deyo comorbidity scores, age, sex, and year of diagnosis. Data analysis was performed from October 2015 through December 2015.

Interventions  Combined-modality therapy, RT, CT.

Main Outcomes and Measures  Survival by treatment cohort was estimated using the Kaplan-Meier method and analyzed using the log rank test, univariate and multivariate Cox models, and propensity score–matched analyses.

Results  A total of 16 717 patients (median [range] age, 73 [65-≥90 y]; 8870 [53%] male) were identified. The median OS by treatment was 9.0 (95% CI, 8.8-9.3) months with CMT (8435 patients), 4.7 (95% CI, 4.5-5.0) months with RT alone (1693 patients), 4.3 (95% CI, 4.0-4.7) months with CT alone (1018 patients), and 2.8 (95% CI, 2.8-2.9) months with no therapy (5571 patients) (P < .001). On multivariate analysis, CMT was superior to both CT alone (hazard ratio, 1.50 [95% CI, 1.40-1.60]; P < .001) and RT alone (hazard ratio, 1.47 [95% CI, 1.39-1.55]; P < .001), whereas no differences were observed between CT alone vs RT alone (P = .60). Propensity score–matched analyses redemonstrated improved OS with CMT over CT alone (P = .002) and RT alone (P < .001); no differences were observed between CT alone vs RT alone (P = .44). On subgroup analyses, a consistent OS advantage was observed with CMT over both CT alone and RT alone across each age stratification (65-69, 70-74, 75-79, and ≥80 years) and among patients treated with or without tumor resection (all P < .001).

Conclusions and Relevance  In this analysis of multimodality therapy for elderly patients with GBM, OS was superior with CMT compared with CT alone and RT alone. Survival was similar between CT alone and RT alone, and both CT alone and RT alone were superior to no therapy. This analysis supports the use of CMT for suitable elderly candidates.

JAMA Neurology 2016

Genetic and phenotypic characterization of complex hereditary spastic paraplegia

The hereditary spastic paraplegias are a heterogeneous group of degenerative disorders that are clinically classified as either pure with predominant lower limb spasticity, or complex where spastic paraplegia is complicated with additional neurological features, and are inherited in autosomal dominant, autosomal recessive or X-linked patterns. Genetic defects have been identified in over 40 different genes, with more than 70 loci in total. Complex recessive spastic paraplegias have in the past been frequently associated with mutations in SPG11 (spatacsin), ZFYVE26/SPG15, SPG7 (paraplegin) and a handful of other rare genes, but many cases remain genetically undefined. The overlap with other neurodegenerative disorders has been implied in a small number of reports, but not in larger disease series. This deficiency has been largely due to the lack of suitable high throughput techniques to investigate the genetic basis of disease, but the recent availability of next generation sequencing can facilitate the identification of disease-causing mutations even in extremely heterogeneous disorders. We investigated a series of 97 index cases with complex spastic paraplegia referred to a tertiary referral neurology centre in London for diagnosis or management. The mean age of onset was 16 years (range 3 to 39). The SPG11 gene was first analysed, revealing homozygous or compound heterozygous mutations in 30/97 (30.9%) of probands, the largest SPG11 series reported to date, and by far the most common cause of complex spastic paraplegia in the UK, with severe and progressive clinical features and other neurological manifestations, linked with magnetic resonance imaging defects. Given the high frequency of SPG11 mutations, we studied the autophagic response to starvation in eight affectedSPG11 cases and control fibroblast cell lines, but in our restricted study we did not observe correlations between disease status and autophagic or lysosomal markers. In the remaining cases, next generation sequencing was carried out revealing variants in a number of other known complex spastic paraplegia genes, including five in SPG7 (5/97), four in FA2H (also known as SPG35) (4/97) and two inZFYVE26/SPG15. Variants were identified in genes usually associated with pure spastic paraplegia and also in the Parkinson’s disease-associated gene ATP13A2, neuronal ceroid lipofuscinosis gene TPP1and the hereditary motor and sensory neuropathy DNMT1 gene, highlighting the genetic heterogeneity of spastic paraplegia. No plausible genetic cause was identified in 51% of probands, likely indicating the existence of as yet unidentified genes.

Brain 2016

TMEM5-associated dystroglycanopathy presenting with CMD and mild limb-girdle muscle involvement.

The dystroglycanopathies, which are caused by reduced glycosylation of alpha-dystroglycan, are a heterogeneous group of neurodegenerative disorders characterized by variable brain and skeletal muscle involvement. Recently, mutations in TMEM5 have been described in severe dystroglycanopathies. We present the clinical, molecular and neuroimaging features of an Italian boy who had delayed developmental milestones with mild limb-girdle muscle involvement, bilateral frontotemporal polymicrogyria, moderate intellectual disability, and no cerebellar involvement. He also presented a cochlear dysplasia and harbored a reported mutation (p.A47Rfs*42) in TMEM5, detected using targeted next-generation sequencing. The relatively milder muscular phenotype and associated structural brain abnormalities distinguish this case from previously reported patients with severe dystroglycanopathies and expand the spectrum of TMEM5-associated disorders.

Neuromuscul Disord. 2016

Bioinformatic profiling identifies an immune-related risk signature for glioblastoma

Objective: To investigate the local immune status and its prognostic value in glioma.

Methods: A cohort of 297 glioma samples with whole genome microarray expression data from the Chinese Glioma Genome Atlas database were included for discovery. The Cancer Genome Atlas (TCGA) database was used for validation. Principal components analysis and gene set enrichment analysis were used to explore the bioinformatic implication.

Results: Distinct local immune status was identified according to histologic grade. Glioblastoma (GBM) exhibited an enhanced immune phenotype compared to lower grade glioma. We profiled the immune-related gene set and identified 8 genes (FOXO3, IL6, IL10, ZBTB16, CCL18, AIMP1, FCGR2B, and MMP9) with the greatest prognostic value in GBM. A local immune-related risk signature was developed from the genes to distinguish cases as high or low risk of unfavorable prognosis, which could be validated in TCGA database. High-risk patients conferred an enhanced intensity of local immune response compared to low-risk ones. Additionally, the signature exhibited different distribution based on molecular features. The signature had prognostic significance in the stratified cohorts and was identified as an independent prognostic factor for GBM.

Conclusions: We profiled the immune status in glioma and established a local immune signature for GBM, which could independently identify patients with a high risk of reduced survival, indicating the relationship between prognosis and local immune response.

Neurology 2016

The APOSTEL recommendations for reporting quantitative optical coherence tomography studies

Objective: To develop consensus recommendations for reporting of quantitative optical coherence tomography (OCT) study results.

Methods: A panel of experienced OCT researchers (including 11 neurologists, 2 ophthalmologists, and 2 neuroscientists) discussed requirements for performing and reporting quantitative analyses of retinal morphology and developed a list of initial recommendations based on experience and previous studies. The list of recommendations was subsequently revised during several meetings of the coordinating group.

Results: We provide a 9-point checklist encompassing aspects deemed relevant when reporting quantitative OCT studies. The areas covered are study protocol, acquisition device, acquisition settings, scanning protocol, funduscopic imaging, postacquisition data selection, postacquisition data analysis, recommended nomenclature, and statistical analysis.

Conclusions: The Advised Protocol for OCT Study Terminology and Elements recommendations include core items to standardize and improve quality of reporting in quantitative OCT studies. The recommendations will make reporting of quantitative OCT studies more consistent and in line with existing standards for reporting research in other biomedical areas. The recommendations originated from expert consensus and thus represent Class IV evidence. They will need to be regularly adjusted according to new insights and practices.

Neurology 2016

Guidelines for Adult Stroke Rehabilitation and Recovery

Purpose—The aim of this guideline is to provide a synopsis of best clinical practices in the rehabilitative care of adults recovering from stroke.

Methods—Writing group members were nominated by the committee chair on the basis of their previous work in relevant topic areas and were approved by the American Heart Association (AHA) Stroke Council’s Scientific Statement Oversight Committee and the AHA’s Manuscript Oversight Committee. The panel reviewed relevant articles on adults using computerized searches of the medical literature through 2014. The evidence is organized within the context of the AHA framework and is classified according to the joint AHA/American College of Cardiology and supplementary AHA methods of classifying the level of certainty and the class and level of evidence. The document underwent extensive AHA internal and external peer review, Stroke Council Leadership review, and Scientific Statements Oversight Committee review before consideration and approval by the AHA Science Advisory and Coordinating Committee.

Results—Stroke rehabilitation requires a sustained and coordinated effort from a large team, including the patient and his or her goals, family and friends, other caregivers (eg, personal care attendants), physicians, nurses, physical and occupational therapists, speech-language pathologists, recreation therapists, psychologists, nutritionists, social workers, and others. Communication and coordination among these team members are paramount in maximizing the effectiveness and efficiency of rehabilitation and underlie this entire guideline. Without communication and coordination, isolated efforts to rehabilitate the stroke survivor are unlikely to achieve their full potential.

Conclusions—As systems of care evolve in response to healthcare reform efforts, postacute care and rehabilitation are often considered a costly area of care to be trimmed but without recognition of their clinical impact and ability to reduce the risk of downstream medical morbidity resulting from immobility, depression, loss of autonomy, and reduced functional independence. The provision of comprehensive rehabilitation programs with adequate resources, dose, and duration is an essential aspect of stroke care and should be a priority in these redesign efforts.

Stroke 2016

Long-term effects of delayed-release dimethyl fumarate in multiple sclerosis: Interim analysis of ENDORSE, a randomized extension study

Background: Delayed-release dimethyl fumarate (DMF) demonstrated strong efficacy and a favorable benefit–risk profile for patients with relapsing–remitting multiple sclerosis (RRMS) in phase 3 DEFINE/CONFIRM studies. ENDORSE is an ongoing long-term extension of DEFINE/CONFIRM.

Objective: We report efficacy and safety results of a 5-year interim analysis of ENDORSE (2 years DEFINE/CONFIRM; minimum 3 years ENDORSE).

Methods: In ENDORSE, patients randomized to DMF 240 mg twice (BID) or thrice daily (TID) in DEFINE/CONFIRM continued this dosage, and those initially randomized to placebo (PBO) or glatiramer acetate (GA) were re-randomized to DMF 240 mg BID or TID.

Results: For patients continuing DMF BID (BID/BID), annualized relapse rates were 0.202, 0.163, 0.139, 0.143, and 0.138 (years 1–5, respectively) and 63%, 73%, and 88% were free of new or enlarging T2 hyperintense lesions, new T1 hypointense lesions, and gadolinium-enhanced lesions, respectively, at year 5. Adverse events (AEs; serious adverse events (SAEs)) were reported in 91% (22%; BID/BID), 95% (24%; PBO/BID), and 88% (16%; GA/BID) of the patients. One case of progressive multifocal leukoencephalopathy was reported in the setting of severe, prolonged lymphopenia.

Conclusion: Treatment with DMF was associated with continuously low clinical and magnetic resonance imaging (MRI) disease activity in patients with RRMS. These interim data demonstrate a sustained treatment benefit and an acceptable safety profile with DMF.

Multiple sclerosis  2016

Cognitive assessment in Amyotrophic Lateral Sclerosis by means of P300-Brain Computer Interface: a preliminary study

Objective: To investigate the use of P300-based Brain Computer Interface (BCI) technology for the administration of motor-verbal free cognitive tests in Amyotrophic Lateral Sclerosis (ALS).

Methods: We recruited 15 ALS patients and 15 age- and education-matched healthy subjects. All participants underwent a BCI-based neuropsychological assessment, together with two standard cognitive screening tools (FAB, MoCA), two psychological questionnaires (BDI, STAI-Y) and a usability questionnaire. For patients, clinical and respiratory examinations were also performed, together with a behavioural assessment (FBI).

Results: Correlations were observed between standard cognitive and BCI-based neuropsychological assessment, mainly concerning execution times in the ALS group. Moreover, patients provided positive rates concerning the BCI perceived usability and subjective experience. Finally, execution times at the BCI-based neuropsychological assessment were useful to discriminate patients from controls, with patients achieving lower processing speed than controls regarding executive functions.

Conclusions: The developed motor-verbal free neuropsychological battery represents an innovative approach, that could provide relevant information for clinical practice and ethical issues. Its use for cognitive evaluation throughout the course of ALS, currently not available by means of standard assessment, must be addressed in further longitudinal validation studies. Further work will be aimed at refining the developed system and enlarging the cognitive spectrum investigated.

Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration 2016

Disability Rating Scales in Parkinson's Disease: Critique and Recommendations

Introduction

PD is associated with impairments that progress over time to disability. A large number of disability scales exist with little information on the best choice in PD.

Methods

Following methodology adopted by the International Parkinson and Movement Disorder Society Task Force, a review of disability scales used in PD was completed. Based on prespecified criteria, the review categorized scales into: “Recommended”; “Recommended with Further Validation in PD Required” when well-validated scales have not been specifically tested for clinimetric properties in PD; “Suggested”; and “Listed.”

Results

Twenty-nine disability instruments were identified with nine scales fulfilling criteria for “Recommended” and 7 “Recommended with Further Validation in PD Required.” Eight scales are “Suggested” and five scales are “Listed” for use in PD. The nine Recommended scales (Functional Status Questionnaire, Lawton-Brody Activities of Daily Living, Nottingham Activities of Daily Living, Schwab and England Activities of Daily Living, Self-Assessment PD Disability, Short Parkinson's Evaluation Scale/Scales for Outcomes in PD, Unified PD Rating Scale–II: Activities of Daily Living, Movement Disorders Society UPDRS Motor Experiences of Daily Living, PROMIS^® and Neuro-QoL Physical Function), and the seven Recommended with Further Validation in PD Required are reviewed.

Conclusion

Many disability measures are available and recommended for application in PD. The Task Force does not recommend the development of a new scale. Selection of the most appropriate instrument for a particular objective requires consideration of the characteristics of each scale and the goals of the assessment.

Movement Disorders 2016