Validation of an ambient measurement system (AMS) for physical activities in a paediatric population.

Ambient measurement systems (AMSs) can enable continuous assessment of functional performance at home, increasing the availability of data for monitoring of neuromuscular disease. An AMS passively measures movement whenever someone is in range of the sensor, without the need for any wearable sensors. The current study evaluates the performance of an AMS for three metrics associated with functional assessments in Duchenne muscular dystrophy (DMD): ambulation speed, rise-to-stand speed and arm-raise speed. Healthy paediatric subjects performed a series of functional tasks and were graded by both a human rater and an AMS. Linear mixed-effect models were fit to calculate agreement between the two measurement methods. For all activities, the AMS and human rater supplied similar measurements of average speed, with correlation coefficients of 0.76-0.92 and systematic differences ranging in magnitude from 0 to 0.48 m per second. The largest systematic difference was for the 10-m run, which was likely due to human rater reaction time. Systematic differences in arm-raise measurements were due to incomplete execution of movements by test participants. These results are consistent with previous studies comparing automated and manual measurements of movement. This study demonstrates that an AMS device is able to measure ambulation speed, rise-to-stand speed and arm-raise speed in a paediatric population in a controlled setting without the need for complicated installation, calibration or worn sensors.

Disease-related determinants of quality of life 10 years after clinically isolated syndrome.

BACKGROUND: The main clinical determinants of quality of life (QOL) 5 years after clinically isolated syndrome (CIS) are Expanded Disability Status Scale (EDSS) score and conversion to clinically definite multiple sclerosis (CDMS). The aim of this study was to determine the demographic, clinical, and magnetic resonance imaging (MRI) factors associated with QOL 10 years after CIS. METHODS: Controlled High Risk Avonex® Multiple Sclerosis Prevention Study in Ongoing Neurologic Surveillance (CHAMPIONS) 10-year patients were assessed for CDMS, EDSS score, MRI T2 activity, brain parenchymal fraction, and patient-reported QOL. Associations were evaluated using analysis of variance models. RESULTS: A second clinical event consistent with CDMS and higher EDSS scores at years 5 and 10 were associated with lower 36-item Short Form Health Status Survey (SF-36) Physical Component Summary scores at year 10 (P < .01). Patients with earlier onset of CDMS had worse patient-reported Physical Component Summary, SF-36 Mental Component Summary, fatigue, and pain scores at year 10 than patients with later or no onset of CDMS. Neither initial randomization group nor any MRI metrics assessed at baseline or during follow-up were associated with QOL at 10 years. CONCLUSIONS: These results support the development of therapies for patients with CIS that significantly reduce the risk of conversion to CDMS and the progression of physical disability to milestones as low as EDSS scores of 2.0.

Aggressive relapsing multiple sclerosis characterized by rapid disability progression.

BACKGROUND: Criteria for identifying relapsing multiple sclerosis (RMS) patients with aggressive disease, which would be useful for clinical decision making, are currently unavailable. OBJECTIVE: Identify RMS patients with aggressive disease characterized by rapid disability progression. METHODS: Data from a 2-year, phase 3, double-blind, placebo-controlled trial with long-term follow-up evaluations of RMS patients taking either intramuscular interferon beta-1a (IM IFNß-1a, 30µg) or placebo with baseline Expanded Disability Status Scale (EDSS) scores of 1.0-3.5 were retrospectively analyzed. Patients with a ≥2.0-point increase in EDSS score, resulting in a score ≥4.0 by study end, were considered to have aggressive RMS. The risk of a poor long-term outcome, defined as an EDSS score ≥8.0 at 8 years of follow-up, was calculated as an odds ratio from a logistic regression model comparing patients with and without aggressive RMS. RESULTS: Only 25 patients met the criteria for aggressive RMS. Among these patients, mean disease duration was 5.1±3.85 years, mean baseline age was 37.2±6.35 years, and mean baseline EDSS score was 2.8±0.74. Fewer IM IFNß-1a-treated than placebo-treated patients met the criteria for aggressive RMS at 2 years (7% vs 22% on placebo, p=0.0072). Thirteen patients reached the EDSS milestone of ≥8.0 by the end of the 8-year follow-up. The odds ratio for attaining severe disability was 86.4 (95% CI, 10.3-726.4; p<0.0001) for patients with aggressive RMS compared to patients without aggressive RMS. CONCLUSIONS: Defining aggressive RMS based on rapid EDSS progression was useful in identifying patients at risk for more severe disease course.

Treatment discontinuation and disease progression with injectable disease-modifying therapies: findings from the north american research committee on multiple sclerosis database.

Injectable first-line disease-modifying therapies (DMTs) for multiple sclerosis (MS) are generally prescribed for continuous use. Accordingly, the various factors that influence patient persistence with treatment and that can lead some patients to switch medications or discontinue treatment may affect clinical outcomes. Using data from the North American Research Committee on Multiple Sclerosis (NARCOMS) database, this study evaluated participants' reasons for discontinuation of injectable DMTs as well as the relationship between staying on therapy and sustained patient-reported disease progression and annualized relapse rates. Participants selected their reason(s) for discontinuation from among 16 possible options covering the categories of efficacy, safety, tolerability, and burden, with multiple responses permitted. Both unadjusted data and data adjusted for baseline age, disease duration, disability, and sex were evaluated. Discontinuation profiles varied among DMTs. Participants on intramuscular interferon beta-1a (IM IFNß-1a) and glatiramer acetate (GA) reported the fewest discontinuations based on safety concerns, although GA was associated with reports of higher burden and lower efficacy than other therapies. Difficulties with tolerability were more often reported as a reason for discontinuing subcutaneous (SC) IFNß-1a than as a reason for discontinuing IM IFNß-1a, GA, or SC IFNß-1b. In the persistent therapy cohort, less patient-reported disability progression was reported with IM IFNß-1a treatment than with SC IFNß-1a, IFNß-1b, or GA. These findings have relevance to clinical decision making and medication compliance in MS patient care.

Derivation of a new ADAS-cog composite using tree-based multivariate analysis: prediction of conversion from mild cognitive impairment to Alzheimer disease.

Model-based statistical approaches were used to compare the ability of the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog), cerebrospinal fluid (CSF), fluorodeoxyglucose positron emission tomography and volumetric magnetic resonance imaging (MRI) markers to predict 12-month progression from mild cognitive impairment (MCI) to Alzheimer disease (AD). Using the Alzheimer's Disease Neuroimaging Initiative (ADNI) data set, properties of the 11-item ADAS-cog (ADAS.11), the 13-item ADAS-cog (ADAS.All) and novel composite scores were compared, using weighting schemes derived from the Random Forests (RF) tree-based multivariate model. Weighting subscores using the RF model of ADAS.All enhanced discrimination between elderly controls, MCI and AD patients. The ability of the RF-weighted ADAS-cog composite and individual scores, along with neuroimaging or biochemical biomarkers to predict MCI to AD conversion over 12 months was also assessed. Although originally optimized to discriminate across diagnostic categories, the ADAS. All, weighted according to the RF model, did nearly as well or better than individual or composite baseline neuroimaging or CSF biomarkers in prediction of 12-month conversion from MCI to AD. These suggest that a modified subscore weighting scheme applied to the 13-item ADAS-cog is comparable to imaging or CSF markers in prediction of conversion from MCI to AD at 12 months.

Safety and tolerability of divalproex sodium extended-release in the prophylaxis of migraine headaches: results of an open-label extension trial in adolescents.

OBJECTIVE: To evaluate the long-term safety and tolerability of divalproex sodium extended-release in the prophylaxis of migraine headaches in adolescents. BACKGROUND: Divalproex sodium has been approved for migraine prophylaxis in adults. A previous double-blind, placebo-controlled study of the efficacy and safety of divalproex sodium extended-release for prevention of migraine in adolescents was followed by the present long-term extension trial, which was designed to collect additional safety and tolerability data. METHODS: This was a 12-month, Phase 3, open-label extension of a 3-month, double-blind, placebo-controlled, multicenter study of adolescents aged 12 to 17 years with migraine headaches who had either completed the previous study or had discontinued because of lack of efficacy. Subjects from the previous trial who had experienced serious adverse events possibly or probably related to study drug were excluded. Divalproex sodium extended-release 500 mg daily was administered for 15 days then increased to 1000 mg. Study visits were conducted at days 1 and 15 and months 1, 2, 3, 6, 9, and 12. Safety assessments included adverse event collection, laboratory testing, physical and neurological examinations, vital signs, and electrocardiograms, as well as reproductive endocrine analyses for postmenarchal female subjects. Efficacy was evaluated by sequential 4-week migraine headache rates calculated from subjects' headache diaries. RESULTS: A total of 112 subjects enrolled in the trial. The most common adverse events were weight gain (15%), nausea (14%), somnolence (12%), upper respiratory tract infection (11%), increased ammonia (8%), and sinusitis (8%). Five (4%) subjects experienced serious adverse events, and 15 (13%) subjects prematurely discontinued because of an adverse event. Increased ammonia levels were noted in some individuals, and the mean ammonia level for all subjects increased 19.2 microm from baseline. No other clinically significant changes were observed in laboratory values, vital signs, or electrocardiograms. Improvement in mean and median 4-week migraine headache rates occurred by the fourth month and lasted for the duration of the trial. CONCLUSIONS: In this long-term open-label extension study, the safety profile of divalproex sodium extended-release in adolescents with migraine was consistent with that observed in the preceding 3-month, double-blind trial and in previous adult studies. Overall, divalproex sodium extended-release was well-tolerated in adolescents aged 12 to 17 years.

Divalproex sodium extended-release for the prophylaxis of migraine headache in adolescents: results of a stand-alone, long-term open-label safety study.

OBJECTIVE: The objective of this long-term open-label study in adolescents was to assess the safety and tolerability of divalproex sodium extended-release in the prophylaxis of migraine headaches. BACKGROUND: Two formulations of divalproex sodium have demonstrated efficacy in the prevention of migraine headaches in adults. However, no medications are currently approved for this indication in adolescents, and long-term safety data on agents for migraine prevention are lacking for this younger population. Therefore, the current study was conducted to assess the long-term safety and tolerability of divalproex extended-release in adolescents with migraine headaches. METHODS: This was a 12-month, phase 3, open-label, multicenter study of adolescents aged 12 to 17 years with migraine headaches diagnosed by International Headache Society criteria. Divalproex sodium extended-release was initiated at 500 mg/day for 15 days then increased to 1000 mg daily, with subsequent adjustments permitted within a dosing range of 250-1000 mg daily. Study visits were conducted at days 1 and 15 and months 1, 2, 3, 6, 9, and 12. Safety was evaluated by adverse event collection, laboratory assessments, physical and neurological examinations, vital signs, electrocardiograms, the Udvalg for Kliniske Undersøgelser Side Effect Rating Scale, the Wechsler Abbreviated Scale of Intelligence, and the Behavioral Assessment Scale for Children. Efficacy was evaluated by following the number of migraine headache days reported in subjects' headache diaries over sequential 4-week intervals for the duration of the trial. RESULTS: A total of 241 subjects were enrolled and treated. The most frequently reported adverse events were nausea (19%), vomiting (18%), weight gain (12%), nasopharyngitis (11%), migraine (10%), and upper respiratory tract infection (10%). Ten (4%) subjects experienced serious adverse events, and 40 (17%) subjects discontinued because of an adverse event. Increases in ammonia levels were observed. No other clinically significant changes were observed in laboratory values, vital signs, rating scales, or electrocardiograms. Median 4-week migraine headache days decreased 75% between the first and the fourth months of the study (from 4.0 to 1.0) and remained at or below this level for the remainder of the study. CONCLUSIONS: In this long-term open-label study of adolescents with migraine, the safety and tolerability profile of divalproex sodium extended-release was consistent with findings from previous trials in adults, as well as 2 studies recently completed in adolescents. In general, divalproex sodium extended-release was well-tolerated in adolescents with migraine.

Divalproex extended-release in adolescent migraine prophylaxis: results of a randomized, double-blind, placebo-controlled study.

OBJECTIVE: To evaluate the efficacy, tolerability, and safety of 3 different doses of divalproex sodium extended-release vs placebo in the prophylaxis of migraine headaches in adolescents. BACKGROUND: Divalproex sodium has been approved for migraine prophylaxis in adults, and previous uncontrolled data suggest divalproex sodium may be effective in preventing migraine in children and adolescents with acceptable tolerability. METHODS: This was a 12-week, phase 3, randomized, placebo-controlled, double-blind, parallel-group, multicenter study in approximately 300 adolescents aged 12 to 17 years with migraine headaches. At the end of the baseline phase, subjects still meeting study criteria were randomized in a 1:1:1:1 ratio to receive divalproex sodium extended-release 250 mg, 500 mg, or 1000 mg once daily, or placebo. The primary efficacy variable was reduction from baseline in 4-week migraine headache rate for each active treatment group vs placebo. Standard safety assessments were conducted and testosterone and sex hormone-binding globulin levels were collected for postmenarchal females. RESULTS: There was no statistically significant treatment difference between any divalproex sodium extended-release dose group and placebo for the primary efficacy variable, reduction from baseline in 4-week migraine headache rate. There were no statistically significant differences in adverse events between any active treatment group and placebo. A notable dose-related decrease in platelets was observed, and individuals in all 4 treatment groups had increases in ammonia levels; treatment differences in other laboratory variables were generally small. Among postmenarchal female subjects who were not taking hormonal contraceptives or other steroids, there was no statistically significant change in testosterone levels, but a statistically significant dose-related increase in sex hormone-binding globulin was observed. CONCLUSIONS: In the current study, divalproex sodium extended-release did not differentiate from placebo in the prophylactic treatment of migraine headaches but was generally well-tolerated in adolescents aged 12 to 17 years.

The molecular pathology of Rett syndrome: synopsis and update.

Genetic mutations of the X-linked gene MECP2, encoding methyl-CpG-binding protein 2, cause Rett syndrome (RTT) and other neurological disorders. It is increasingly recognized that MECP2 is a multifunctional protein, with at least four different functional domains: (1) a methyl-CpG-binding domain; (2) an arginine-glycine repeat RNA-binding domain; (3) a transcriptional repression domain; and (4) an RNA splicing factor binding region (WW group II binding domain). There is evidence that MECP2 is important for large-scale reorganization of pericentromeric heterochromatin during differentiation. Studies in MECP2-deficient mouse brain have identified a diverse set of genes with altered levels of mRNA expression or splicing. It is still unclear how altered MECP2 function ultimately results in neuronal disease after a period of grossly normal development. However, mounting evidence suggests that neuronal health and development depend on precise regulation of MECP2 expression. In genetically engineered mice, both increased and decreased levels of MECP2 result in a neurological phenotype. Furthermore, it was recently discovered that MECP2 gene duplications underlie a small number of atypical Rett cases and mental retardation syndromes. The finding that MECP2 levels are tightly regulated in neurons has important implications for the design of gene replacement or reactivation strategies for treatment of RTT, because affected individuals typically are somatic mosaics with one set of cells expressing a mutated MECP2 from the affected X, and another set expressing normal MECP2 from the unaffected X. Further studies are necessary to elucidate the molecular pathology of both loss-of-function and gain-of-function mutations in MECP2.