Measurement of upper limb function in ALS: a structured review of current methods and future directions.

Measurement of upper limb function is critical for tracking clinical severity in amyotrophic lateral sclerosis (ALS). The Amyotrophic Lateral Sclerosis Rating Scale-revised (ALSFRS-r) is the primary outcome measure utilised in clinical trials and research in ALS. This scale is limited by floor and ceiling effects within subscales, such that clinically meaningful changes for subjects are often missed, impacting upon the evaluation of new drugs and treatments. Technology has the potential to provide sensitive, objective outcome measurement. This paper is a structured review of current methods and future trends in the measurement of upper limb function with a particular focus on ALS. Technologies that have the potential to radically change the upper limb measurement field and explore the limitations of current technological sensors and solutions in terms of costs and user suitability are discussed. The field is expanding but there remains an unmet need for simple, sensitive and clinically meaningful tests of upper limb function in ALS along with identifying consensus on the direction technology must take to meet this need.

Designing rare disease care pathways in the Republic of Ireland: a co-operative model.

BACKGROUND: Rare diseases (RDs) are often complex, serious, chronic and multi-systemic conditions, associated with physical, sensory and intellectual disability. Patients require follow-up management from multiple medical specialists and health and social care professionals involving a high level of integrated care, service coordination and specified care pathways. METHODS AND OBJECTIVES: This pilot study aimed to explore the best approach for developing national RD care pathways in the Irish healthcare system in the context of a lack of agreed methodology. Irish clinical specialists and patient/lived experience experts were asked to map existing practice against evidence-based clinical practice guidelines (CPGs) and best practice recommendations from the European Reference Networks (ERNs) to develop optimal care pathways. The study focused on the more prevalent, multisystemic rare conditions that require multidisciplinary care, services, supports and therapeutic interventions. RESULTS: 29 rare conditions were selected across 18 ERNs, for care pathway development. Multidisciplinary input from multiple specialisms was relevant for all pathways. A high level of engagement was experienced from clinical leads and patient organisations. CPGs were identified for 26 of the conditions. Nurse specialist, Psychology, Medical Social Work and Database Manager roles were deemed essential for all care pathways. Access to the therapeutic Health Service Professionals: Physiotherapy, Occupational Therapy, and Speech and Language Therapy were seen as key requirements for holistic care. Genetic counselling was highlighted as a core discipline in 27 pathways demonstrating the importance of access to Clinical Genetics services for many people with RDs. CONCLUSIONS: This study proposes a methodology for Irish RD care pathway development, in collaboration with patient/service user advocates. Common RD patient needs and health care professional interventions across all pathways were identified. Key RD stakeholders have endorsed this national care pathway initiative. Future research focused on the implementation of such care pathways is a priority.

Respiratory measurements and airway clearance device prescription over one year in amyotrophic lateral sclerosis.

Objective: The rates of decline in respiratory measurements, including Peak Cough Flow (PCF) have not been established in Amyotrophic Lateral Sclerosis (ALS). Additionally, optimal prescription of cough adjuncts which aim to increase cough strength are unknown. The primary aim of this study was to quantify declines in respiratory function in ALS using PCF, Sniff Nasal Inspiratory Pressure (SNIP) and Slow Vital Capacity (SVC). Secondary aims were to measure respiratory morbidity, audit the characteristics of those prescribed cough adjuncts, and compare outcomes between treated and untreated cohorts. Methods: A prospective, longitudinal, observational, cohort study evaluated respiratory measures, morbidity, and physical function in ALS patients at three monthly intervals, over one year. Patient and disease characteristics of those prescribed cough adjuncts were profiled at the time of device prescription. Results: one hundred and eight participants with mean age 62.1 ± 11.5 years participated. PCF declined rapidly at a rate of 124.8L/min/year (p < 0.001). SNIP, SVC (%predicted), and ALSFRS-R also declined significantly at rates of 18.72cmH2O, 17.49%, and 9.62 units per year respectively (p < 0.001). Thirty-two (29.6%) patients reported 56 incidences of chest infection and 21 died. Patients prescribed a cough adjunct (44.4%) had significantly lower average PCF, SNIP, SVC percent predicted, and ALSFRS-R (p < 0.001). Conclusions: This study identified a rapid rate of decline in PCF, a similar decline in SNIP, and slower declines in SVC and ALSFRS-R. Cough adjunct prescription was triggered by declining respiratory measures and recommended PCF thresholds, but also by respiratory symptoms. Chest infections were common in patients regardless of cough adjunct prescription and should be closely monitored.

Genetic effects influencing risk for major depressive disorder in China and Europe.

Major depressive disorder (MDD) is a common, complex psychiatric disorder and a leading cause of disability worldwide. Despite twin studies indicating its modest heritability (~30-40%), extensive heterogeneity and a complex genetic architecture have complicated efforts to detect associated genetic risk variants. We combined single-nucleotide polymorphism (SNP) summary statistics from the CONVERGE and PGC studies of MDD, representing 10 502 Chinese (5282 cases and 5220 controls) and 18 663 European (9447 cases and 9215 controls) subjects. We determined the fraction of SNPs displaying consistent directions of effect, assessed the significance of polygenic risk scores and estimated the genetic correlation of MDD across ancestries. Subsequent trans-ancestry meta-analyses combined SNP-level evidence of association. Sign tests and polygenic score profiling weakly support an overlap of SNP effects between East Asian and European populations. We estimated the trans-ancestry genetic correlation of lifetime MDD as 0.33; female-only and recurrent MDD yielded estimates of 0.40 and 0.41, respectively. Common variants downstream of GPHN achieved genome-wide significance by Bayesian trans-ancestry meta-analysis (rs9323497; log10 Bayes Factor=8.08) but failed to replicate in an independent European sample (P=0.911). Gene-set enrichment analyses indicate enrichment of genes involved in neuronal development and axonal trafficking. We successfully demonstrate a partially shared polygenic basis of MDD in East Asian and European populations. Taken together, these findings support a complex etiology for MDD and possible population differences in predisposing genetic factors, with important implications for future genetic studies.

Atypical social cognitive processing in premotor Huntington's disease: a single case study.

BACKGROUND: We report the case of a 52-year-old male with pre-motor Huntington's disease (HD) who has undergone detailed clinical and neuropsychological examination. This patient's negative symptomatology and behavioural change are having a detrimental impact on his social, occupational and interpersonal life, in the absence of motor symptoms. METHODS: The patient has undergone repeat neuropsychological testing (T1 aged 50; T2 aged 52) with particular focus on executive function and social cognition on repeat testing. RESULTS: This case details a specific manifestation of HD relating to behavioural, psychiatric and social affective deficits. CONCLUSIONS: This case illustrates how social cognitive changes can occur in HD, months and even years prior to the onset of motor features and how such unrecognized deficits can have a deleterious impact on an individual's functional ability and lifestyle, before the disease is traditionally considered to have become manifest.

The effects of a home-based arm ergometry exercise programme on physical fitness, fatigue and activity in Polio survivors: a randomised controlled trial.

OBJECTIVE: To investigate the effect of an eight-week home-based arm ergometry aerobic exercise programme on physical fitness, fatigue, activity and quality of life in Polio Survivors. DESIGN: An assessor blinded randomised controlled trial. SETTING: Home-based exercise. SUBJECTS: Fifty-five Polio survivors randomised to exercise or control groups. INTERVENTION: Home-based arm ergometry at an intensity of 50%-70% maximum heart rate, compared with usual physiotherapy care. MAIN MEASURES: The Six-minute Arm Test, Fatigue Severity Scale, Physical Activity Scale for Individuals with Physical Disabilities and SF-36. Assessments were completed at baseline and at eight weeks. RESULTS: There was no significant difference in the primary outcome, exercising heart rate during the Six-minute Arm Test, between the groups at follow-up [97.6 (SD10.1) compared to 102.4 (SD13.7) beats per minute ( P=0.20)]. Blood pressure was significantly lower in the intervention group at follow-up [systolic blood pressure 132(18.6)mmHg compared to 144.1(14.6)mmHg ( P=0.002)]. There were no between group differences in the Fatigue Severity Scale ( P=0.25) or Physical Activity Scale for Individuals with Physical Disabilities ( P=0.49), with a small difference in SF-36 physical component score ( P=0.04). CONCLUSIONS: This home-based arm ergometry programme successfully facilitated aerobic exercise in Polio Survivors, but did not result in a significant change in physical fitness, measured by the Six-minute Arm Test.

The segmental diffusivity profile of amyotrophic lateral sclerosis associated white matter degeneration.

BACKGROUND AND PURPOSE: Magnetic resonance diffusivity indices have been repeatedly proposed as biomarkers of neurodegeneration in amyotrophic lateral sclerosis (ALS), but no consensus exists as to which diffusivity parameter is the most sensitive to identify early degenerative changes. Despite numerous studies, surprisingly little is known of the segmental vulnerability of the corticospinal tracts and corpus callosum. Our objective was to characterize the core three-dimensional white matter signature of ALS, to describe phenotype-specific patterns of white matter degeneration and to evaluate the diffusivity profile of individual patients and controls in specific white matter segments. METHODS: A large neuroimaging study was undertaken with 62 patients and 55 age-matched healthy controls. White matter alterations were explored based on fractional anisotropy and radial, mean and axial diffusivity indices. Atlas-based region of interest analyses were carried out in the corona radiata, internal capsules, cerebral peduncles, and in the splenium, body and genu of the corpus callosum. Percentage change and receiver operating characteristic (ROC) curves were used to characterize disease-state discriminating diffusivity measures and white matter regions. RESULTS: Bulbar onset patients exhibit extensive corticobulbar tract involvement in the genu of the internal capsule and in the lateral fibres of the corona radiata subjacent to the bulbar representation of the motor homunculus. Spinal onset patients show predominantly posterior internal capsule involvement and medial corona radiata pathology. ROC curve analyses revealed that diffusivity measures of the cerebral crura best discriminate patients and controls (area under the curve 80.1%). CONCLUSIONS: Amyotrophic lateral sclerosis is associated with a core, disease-specific three-dimensional white matter signature which is best demonstrated by radial diffusivity measurements. The main ALS motor phenotypes are manifestations of the relatively selective involvement of corticospinal and corticobulbar fibres.

Patient journey to a specialist amyotrophic lateral sclerosis multidisciplinary clinic: an exploratory study.

BACKGROUND: The multidisciplinary approach in the management of Amyotrophic Lateral Sclerosis (ALS) has been shown to provide superior care to devolved care, with better survival, improved quality of care, and quality of life. Access to expert multidisciplinary management should be a standard for patients with ALS. This analysis explores the patient journey from symptom onset and first engagement with health services, to the initial visit to a specialist ALS Multidisciplinary Clinic (MDC) in Dublin, Ireland. METHODS: A retrospective exploratory multi-method study details the patient journey to the MDC. Data from medical interviews and systematic chart review identifies interactions with the health services and key timelines for thirty five new patients presenting with a diagnosis of ALS during a 6 month period in 2013. RESULTS: The time from first symptom to diagnosis was a mean of 16 months (median 13 months), with a mean interval of 19 months (median 14.6) from first symptoms to arrival at the MDC. The majority of patients were seen by a general practitioner, and subsequently by neurology services. There was an average of four contacts with health services and 4.8 investigations/tests, prior to their first Clinic visit. On the first visit to the MDC patients are linked into an integrated 'system' that can provide specialist care and link with voluntary, palliative and community services as required. CONCLUSIONS: Engagement with a multidisciplinary team has implications for service utilization and quality of life of patients and their families. We have demonstrated that barriers exist that delay referral to specialist services. Comprehensive data recording and collection, using multiple data sources can reconstruct the timelines of the patient journey, which can in turn be used to identify pathways that can expedite early referral to specialist services.

On the development of markers for pathological TDP-43 in amyotrophic lateral sclerosis with and without dementia.

Pathological 43-kDa transactive response sequence DNA-binding protein (TDP-43) has been recognized as the major disease protein in amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration with ubiquitin positive, tau and α-synuclein negative inclusions (FTLD-U) and the transitional forms between these multisystem conditions. In order to develop TDP-43 into a successful ALS biomarker, the natural history of TDP-43 pathology needs to be characterized and the underlying pathophysiology established. Here we propose a spatial and temporal "two-axes" model of central nervous system vulnerability for TDP-43 linked degeneration and review recent studies on potential biomarkers related to pathological TDP-43 in the cerebrospinal fluid (CSF), blood, and skeletal muscle. The model includes the following two arms: Firstly, a "motor neuron disease" or "spinal cord/brainstem to motor cortex" axis (with degeneration possibly ascending from the lower motor neurons to the upper motor neurons); and secondly, a "dementia" or "corticoid/allocortex to neocortex" axis (with a probable spread of TDP-43 linked degeneration from the mediotemporal lobe to wider mesocortical and neocortical brain areas). At the cellular level, there is a gradual disappearance of normal TDP-43 in the nucleus in combination with the formation of pathological aggregates in the cell body and cellular processes, which can also be used to identify the stage of the disease process. Moreover, TDP-43 lesions in subpial/subependymal or perivascular localizations have been noted, and this might account for increased CSF and blood TDP-43 levels through mechanisms that remain to be elucidated.

Executive dysfunction is a negative prognostic indicator in patients with ALS without dementia.

BACKGROUND: The prognostic implications of cognitive impairment in amyotrophic lateral sclerosis (ALS) are not established. OBJECTIVES: To investigate the survival effect of the comorbid frontotemporal dementia (FTD) and to determine whether, in the absence of dementia, impairment in different cognitive domains affects outcome. METHODS: A prospective population-based study of incident cases of ALS in the Republic of Ireland included home-based neuropsychological assessments using age-, sex-, and education-matched controls. Four cognitive domains were evaluated: executive function, memory, language, and visuospatial skills. RESULTS: Mean age of the participants (n = 139) was 63.3 years; 61.2% were male and 35.3% had bulbar-onset ALS. Factors associated with shorter survival included age more than 60, severe disability at baseline, shorter delay to diagnosis, and early respiratory involvement. Comorbid FTD was associated with significantly shorter survival time (hazard ratio [HR] 2.67, 95% confidence interval [CI] 1.04-6.85, p = 0.041). In patients with ALS without dementia, the presence of executive dysfunction was significantly associated with shorter survival. This was confirmed in a multivariate model that included age, delay to diagnosis, disease severity at baseline, education, and respiratory status (HR 3.44, 95% CI 1.45-8.18, p = 0.005). In the absence of executive dysfunction, single or multi-domain impairment in other cognitive domains had no significant effect on survival. CONCLUSION: Comorbid frontotemporal dementia is a negative prognostic indicator. In patients with ALS without dementia, executive dysfunction, but not impairment in other cognitive domains, is an important negative prognostic indicator.

Reduced frequency of ALS in an ethnically mixed population: a population-based mortality study.

OBJECTIVE: To describe ALS mortality rates in the well-characterized ethnically mixed Cuban population over a 6-year period. BACKGROUND: There have been few population-based epidemiologic studies of ALS in non-Europeans. Preliminary data from the United States suggest a lower frequency of ALS in Hispanic and African groups compared with those of European descent. The Cuban population of 11 million comprises three main ancestral groups classified by skin color as white (65%), mixed (24%), and (black 10%). Medical care is of a high standard and is free. Cuba is ideally placed to establish the frequency of ALS in an admixed population of diverse ethnic origin. METHODS: Multiple-cause mortality files from the Central Statistics office in Cuba for the years 2001 through to 2006 were searched for codes corresponding to ALS. Age-adjusted mortality rates were calculated by sex, race/ethnicity, age, and geographic region at time of death. RESULTS: Four hundred thirty-two patients with a diagnosis of ALS were identified. The mean age at death was 63.7 years. There was a slight male predominance (1.1:1). The adjusted death rate from ALS for the total population older than 15 years was 0.83 per 100,000. The adjusted mortality rate per 100,000 was considerably lower in the mixed population (0.55; confidence interval [CI] 0.4-0.72) than in whites (0.93; CI 0.83-1.03) and blacks (0.87; CI 0.62-1.17). There was no correlation between the number of neurologists in each region and the mortality rate from ALS (r = 0.268, p = 0.335). CONCLUSIONS: The overall mortality rate from ALS in Cuba is similar to that described in Hispanic populations in the United States and is lower than in Northern European populations. Mortality from ALS is lowest in a population of mixed ancestry. Ancestral origin is likely to play a role in ALS susceptibility.

A large-scale international meta-analysis of paraoxonase gene polymorphisms in sporadic ALS.

BACKGROUND: Six candidate gene studies report a genetic association of DNA variants within the paraoxonase locus with sporadic amyotrophic lateral sclerosis (ALS). However, several other large studies, including five genome-wide association studies, have not duplicated this finding. METHODS: We conducted a meta-analysis of 10 published studies and one unpublished study of the paraoxonase locus, encompassing 4,037 ALS cases and 4,609 controls, including genome-wide association data from 2,018 ALS cases and 2,425 controls. RESULTS: The combined fixed effects odds ratio (OR) for rs662 (PON1 Q192R) was 1.09 (95% confidence interval [CI], 1.02-1.16, p = 0.01); the genotypic OR for RR homozygotes at Q192R was 1.25 (95% CI, 1.07-1.45, p = 0.0004); the combined OR for rs854560 (PON1 L55M) was 0.97 (95% CI, 0.86-1.10, p = 0.62); the OR for rs10487132 (PON2) was 1.08 (95% CI, 0.92-1.27, p = 0.35). Although the rs662 polymorphism reached a nominal level of significance, no polymorphism was significant after multiple testing correction. In the subanalysis of samples with genome-wide data from which population outliers were removed, rs662 had an OR of 1.06 (95% CI, 0.97-1.16, p = 0.22). CONCLUSIONS: In contrast to previous positive smaller studies, our genetic meta-analysis showed no significant association of amyotrophic lateral sclerosis (ALS) with the PON locus. This is the largest meta-analysis of a candidate gene in ALS to date and the first ALS meta-analysis to include data from whole genome association studies. The findings reinforce the need for much larger and more collaborative investigations of the genetic determinants of ALS.

An all-Ireland epidemiological study of MND, 2004-2005.

BACKGROUND AND METHODS: We conducted an all-Ireland population-based prospective epidemiological survey of motor neurone disease (MND) using the Northern Ireland and Republic of Ireland MND registers to examine the incidence and prevalence of the disease over the period 2004-2005. RESULTS AND CONCLUSIONS: Incidence of MND was 1.9 per 100 000 person-years and rates were comparable in both the north and south of Ireland. Prevalence of MND was 5.0 per 100 000 population. When compared with previous published surveys of MND performed in the Republic of Ireland over the last 10 years, rates of disease have remained relatively constant. When standardized to the 1990 US population, the incidence of MND in Ireland was found to be consistent with other European prospective surveys of MND.

Vacuolar leucoencephalopathy and pulvinar sign in association with coeliac disease.

Several neurological disorders have been associated with coeliac disease, including epilepsy, ataxia and neuropathy. Here we report a rare case of white matter disease in a 55-year-old man with coeliac disease. He presented with anxiety, headache and left upper limb jerking. He subsequently developed epilepsy and brain MRI revealed diffuse white matter abnormality. He died 6 months after presentation due to status epilepticus and sepsis. Brain biopsy demonstrated vacuolar leucoencephalopathy with no evidence of vCJD. An extensive clinical screen excluded infectious, inflammatory and para-neoplastic causes for this condition. Coeliac disease may be causally associated with vacuolar leucoencephalopathy in this case.

Descriptive epidemiology of amyotrophic lateral sclerosis: new evidence and unsolved issues.

Amyotrophic lateral sclerosis (ALS) is a relatively rare disease with a reported population incidence of between 1.5 and 2.5 per 100,000 per year. Over the past 10 years, the design of ALS epidemiological studies has evolved to focus on a prospective, population based methodology, employing the El Escorial criteria and multiple sources of data to ensure complete case ascertainment. Five such studies, based in Europe and North America, have been published and show remarkably consistent incidence figures among their respective Caucasian populations. Population based studies have been useful in defining clinical characteristics and prognostic indicators in ALS. However, many epidemiological questions remain that cannot be resolved by any of the existing population based datasets. The working hypotheses is that ALS, like other chronic diseases, is a complex genetic condition, and the relative contributions of individual environmental and genetic factors are likely to be relatively small. Larger studies are required to characterise risks and identify subpopulations that might be suitable for further study. This current paper outlines the contribution of the various population based registers, identifies the limitations of the existing datasets and proposes a mechanism to improve the future design and output of descriptive epidemiological studies.

Epidemiology and clinical features of amyotrophic lateral sclerosis in Ireland between 1995 and 2004.

BACKGROUND: We conducted a prospective, population based study to examine trends in incidence and prevalence of amyotrophic lateral sclerosis (ALS) in Ireland from 1995 to 2004. METHODS: The Irish ALS Register was used to identify Irish residents diagnosed with ALS between the 3 year period from 1 January 1995 to 31 December 1997 and the 3 year period from 1 January 2002 to 31 December 2004. RESULTS: 465 Irish residents were diagnosed with ALS during the study periods. The annual incidence rate of ALS in Ireland remained stable over this time (2.0 cases per 100,000 person-years; 95% CI 1.9, 2.2). Median survival of Irish ALS patients was 16.4 months and did not change during the study period. Demographics and clinical features of the incident and prevalent Irish ALS cohorts were markedly different.