Survival prediction in sporadic amyotrophic lateral sclerosis. Age and clinical form at onset are independent risk factors

Comparison Of King's Clinical Staging In Multinational Amyotrophic Lateral Sclerosis Cohorts

Background: Amyotrophic lateral sclerosis (ALS) shows considerable clinical heterogeneity, which affects clinical trials. A clinical staging system has been proposed for ALS with potential applications in patient care, research, trial design and health economic analyses. The King's system consists of five stages. We have previously shown that progressive clinical stages were reached at predictable proportions through the disease course, but this needs to be validated in other independent samples. Objectives: We aimed to compare King's clinical staging in ALS in four patient groups, located in different regions and countries and using different health care systems from the original study population in South London. Methods: Clinical data were extracted from two European phase 3 randomized controlled trials (MitoTarget and LiCALS) and from two databases predominately from the United States: the PRO-ACT Consortium Database and a database of patients from the PatientsLikeMe website. Clinical stage was estimated using an algorithm, and standardized time to each clinical stage was calculated in deceased patients. Results: 8,796 patients were included, of whom 1,959 had died by the end of follow-up. Stages occurred in the same order as in the original study for all cohorts. Median standardized times to stages (interquartile range) were Stage 2: 0.61 (0.47-0.75), Stage 3: 0.68 (0.56-0.81), Stage 4A: 0.82 (0.71-0.91), Stage 4B: 0.82 (0.69-0.92) and Stage 4 0.80 (0.67-0.91). Discussion: Timings for all stages were similar to those reported in the original study, except Stage 2 which occurred later in the clinical trial databases due to recruitment occurring after diagnosis.

Deep learning methods to predict amyotrophic lateral sclerosis disease progression

Amyotrophic lateral sclerosis (ALS) is a highly complex and heterogeneous neurodegenerative disease that affects motor neurons. Since life expectancy is relatively low, it is essential to promptly understand the course of the disease to better target the patient's treatment. Predictive models for disease progression are thus of great interest. One of the most extensive and well-studied open-access data resources for ALS is the Pooled Resource Open-Access ALS Clinical Trials (PRO-ACT) repository. In 2015, the DREAM-Phil Bowen ALS Prediction Prize4Life Challenge was held on PRO-ACT data, where competitors were asked to develop machine learning algorithms to predict disease progression measured through the slope of the ALSFRS score between 3 and 12 months. However, although it has already been successfully applied in several studies on ALS patients, to the best of our knowledge deep learning approaches still remain unexplored on the ALSFRS slope prediction in PRO-ACT cohort. Here, we investigate how deep learning models perform in predicting ALS progression using the PRO-ACT data. We developed three models based on different architectures that showed comparable or better performance with respect to the state-of-the-art models, thus representing a valid alternative to predict ALS disease progression.

What do we know about the variability in survival of patients with amyotrophic lateral sclerosis?

INTRODUCTION

ALS is a fatal neurodegenerative disease. However, patients show variability in the length of survival after symptom onset. Understanding the mechanisms of long survival could lead to possible avenues for therapy.

AREAS COVERED

This review surveys the reported length of survival in ALS, the clinical features that predict survival in individual patients, and possible factors, particularly genetic factors, that could cause short or long survival. The authors also speculate on possible mechanisms.

EXPERT OPINION

a small number of known factors can explain some variability in ALS survival. However, other disease-modifying factors likely exist. Factors that alter motor neurone vulnerability and immune, metabolic, and muscle function could affect survival by modulating the disease process. Knowing these factors could lead to interventions to change the course of the disease. The authors suggest a broad approach is needed to quantify the proportion of variation survival attributable to genetic and non-genetic factors and to identify and estimate the effect size of specific factors. Studies of this nature could not only identify novel avenues for therapeutic research but also play an important role in clinical trial design and personalized medicine.

Atypical Motor Neuron Disease variants: Still a diagnostic challenge in Neurology

Motor neuron disease (MND) represents a wide and heterogeneous expanding group of disorders involving the upper or lower motor neurons, mainly represented by amyotrophic lateral sclerosis (ALS), primary lateral sclerosis, progressive muscular atrophy and progressive bulbar palsy. Primary motor neuronopathies are characterized by progressive degenerative loss of anterior horn cell motoneurons (lower motor neurons) or loss of giant pyramidal Betz cells (upper motor neurons). Despite its well-known natural history, pathophysiological and clinical characteristics for the most common MND, atypical clinical presentation and neurodegenerative mechanisms are commonly observed in rare clinical entities, so-called atypical variants of MND-ALS, including flail-leg syndrome, flail-arm syndrome, facial-onset sensory and motor neuronopathy (FOSMN), finger extension weakness and downbeat nystagmus (FEWDON-MND) and long-lasting and juvenile MND-ALS. Herein, we provide a review article presenting clinical, genetic, pathophysiological and neuroimaging findings of atypical variants of MND-ALS in clinical practice.

Activation of Phosphotyrosine-Mediated Signaling Pathways in the Cortex and Spinal Cord of SOD1G93A, a Mouse Model of Familial Amyotrophic Lateral Sclerosis

Degeneration of cortical and spinal motor neurons is the typical feature of amyotrophic lateral sclerosis (ALS), a progressive neurodegenerative disease for which a pathogenetic role for the Cu/Zn superoxide dismutase (SOD1) has been demonstrated. Mice overexpressing a mutated form of the SOD1 gene (SOD1^G93A) develop a syndrome that closely resembles the human disease. The SOD1 mutations confer to this enzyme a “gain-of-function,” leading to increased production of reactive oxygen species. Several oxidants induce tyrosine phosphorylation through direct stimulation of kinases and/or phosphatases. In this study, we analyzed the activities of src and fyn tyrosine kinases and of protein tyrosine phosphatases in synaptosomal fractions prepared from the motor cortex and spinal cord of transgenic mice expressing SOD1^G93A. We found that (i) protein phosphotyrosine level is increased, (ii) src and fyn activities are upregulated, and (iii) the activity of tyrosine phosphatases, including the striatal-enriched tyrosine phosphatase (STEP), is significantly decreased. Moreover, the NMDA receptor (NMDAR) subunit GluN2B tyrosine phosphorylation was upregulated in SOD1^G93A. Tyrosine phosphorylation of GluN2B subunits regulates the NMDAR function and the recruitment of downstream signaling molecules. Indeed, we found that proline-rich tyrosine kinase 2 (Pyk2) and ERK1/2 kinase are upregulated in SOD1^G93A mice. These results point out an involvement of tyrosine kinases and phosphatases in the pathogenesis of ALS.

Therapeutic effects of percutaneous endoscopic gastrostomy on survival in patients with amyotrophic lateral sclerosis: A meta-analysis

Percutaneous endoscopic gastrostomy (PEG) is a method widely used for patients with amyotrophic lateral sclerosis (ALS); nevertheless, its effect on survival remains unclear. The purpose of this meta-analysis study was to determine the effects of PEG on survival in ALS patients. Relevant studies were retrieved from PubMed, EmBase, and the Cochrane Library databases, from inception to June 2017. Studies comparing PEG with other procedures in ALS patients were included. Odds ratios (ORs) in a random-effects model were used to assess the survival at different follow-up periods. Briefly, ten studies involving a total of 996 ALS patients were included. Summary ORs indicated that PEG administration was not associated with 30-day (OR = 1.59; 95%CI 0.93–2.71; P = 0.092), 10-month (OR = 1.25; 95%CI 0.72–2.17; P = 0.436), and 30-month (OR = 1.28; 95% CI 0.77–2.11; P = 0.338) survival rates, while they showed a beneficial effect in 20-month survival rate (OR = 1.97; 95%CI 1.21–3.21; P = 0.007). The survival rate was significantly prominent in reports published before 2005, and in studies with a retrospective design, sample size <100, mean age <60.0 years, and percentage male ≥50.0%. To sum up, these findings suggested that ALS patients administered with PEG had an increased 20-month survival rates, while there was no significant effect in 30-day, 10-month, and 30-month survival rates.

Standard Equations Are Not Accurate in Assessing Resting Energy Expenditure in Patients With Amyotrophic Lateral Sclerosis

OBJECTIVE

To assess the utility of standard equations for calculating caloric requirements in patients with amyotrophic lateral sclerosis (ALS).

BACKGROUND

Malnutrition substantially increases the risk of death in ALS. Weight loss can be stabilized and survival prolonged with early gastrostomy feeding. However the use of standard nutrition equations has not been validated in this population. We therefore compared measured caloric expenditure to 2 predictive equations in patients with varying stages of ALS.

METHODS

Thirty-four patients were studied. Caloric expenditure and respiratory quotient (R) were measured using indirect calorimetry. Results were compared with the Harris-Benedict equation.

RESULTS

The prediction error for the Harris-Benedict equation was 18.6 + 14.9%. Limits of agreement showed this equation could overestimate caloric expenditure by 591 kcal/d and underestimate requirements by 677 kcal/d. R was >0.86 in 11 patients, suggesting overfeeding, and <0.8 in 15 patients, suggesting underfeeding. The difference between predicted and measured caloric expenditure did not correlate with disease severity, disease duration, or body mass index. Mechanically ventilated patients had higher than predicted energy expenditure.

CONCLUSIONS

We found that standard equations used to calculate energy expenditure were not valid for patients with ALS. Moreover, the majority of our patients were either overfed or underfed. As underfeeding can cause diaphragm impairment, and overfeeding can increase ventilatory load, indirect calorimetry should be considered in ALS patients to determine optimal caloric requirement.

The Prognostic Role of Obstructive Sleep Apnea at the Onset of Amyotrophic Lateral Sclerosis

BACKGROUND/OBJECTIVE

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by the progressive loss of central and peripheral motor neurons. Some studies have found discordant data in the presence of sleep apnea in ALS patients. An obstructive component also occurs with upper airways hypotonia and muscle weakness that may result in an excessive reduction of airway lumen, leading to obstructive sleep apnea (OSA). The aim of this study was to assess the role of obstructive apneic events at disease onset in the ALS prognosis.

METHODS

A longitudinal retrospective study was conducted on 42 clinically diagnosed ALS patients. The study population was divided into 2 groups according to their obstructive apnea/hypopnea index (AHIo): group 1 consisted of 20 patients with an AHIo ≥5 and group 2 consisted of 22 patients with an AHIo <5. Both groups were compared with regard to demographic, polygraphic, and respiratory function parameters as well as ALS characteristics (bulbar onset, time between onset and first check-up, time between diagnosis and first check-up, time between first check-up and death or tracheostomy).

RESULTS

The mean survival in ALS patients with an AHIo ≥5 was significantly shorter than in ALS without OSA (p = 0.0237). The sniff nasal inspiratory pressure test was significantly correlated with AHIo, time of oxyhemoglobin saturation below 90% and the oxyhemoglobin desaturation index (p < 0.0001).

CONCLUSIONS

Our study highlights the importance of an early diagnosis of OSA in ALS patients, allowing the identification of ALS patients with an OSA phenotype (AHIo ≥5), who are characterized by a worse prognosis.

Prognostic factors and survival of ALS patients from Belgrade, Serbia

Our aim was to assess the incidence, survival and its prognostic factors in ALS patients from the area of the City of Belgrade, Serbia. A retrospective analysis included 325 probable or definite ALS cases from all five Belgrade neurology departments in the period 1992-2009. Each patient was regularly followed up during the disease until death or until 31 December 2009. Results showed that the average annual ALS incidence rate was 1.11 per 100,000 inhabitants. Male predominance was registered, except for patients with ALS onset after the age of 80 years. Mean survival from the first symptoms was 4.4 ± 0.2 years. Cumulative probability of survival was 71% for two years, 24% for five years, and 17% for seven years. Patients with diagnostic delay longer than 1.6 years had a 1.4-times better chance for survival (p <0.01). Spinal-onset patients on riluzole therapy had 1.8-times better survival (p < 0.01). Patients with early-onset ALS and higher ALSFRS-R score at initial evaluation also had somewhat better survival (p < 0.05). In conclusion, the average annual ALS incidence rate was 1.11 per 100,000 inhabitants. Longer survival was observed in patients with early onset, longer diagnostic delay, less functional impairment at the time of diagnosis, and riluzole treatment.

Epidemiology of amyotrophic lateral sclerosis: A review of literature

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease of motor neurons, resulting in worsening weakness of voluntary muscles until death occurs from respiratory failure. The incidence of ALS in European populations is two to three people per year per 100,000 of the general population. In Europe, crude prevalences range from 1.1/100,000 population in Yugoslavia to 8.2/100,000 in the Faroe Islands. Major advances have been made in our understanding of the genetic causes of ALS, whereas the contribution of environmental factors has been more difficult to assess and large-scale studies have not yet revealed a replicable, definitive environmental risk factor. The only established risk factors to date are older age, male gender and a family history of ALS. Median survival time from onset to death is usually 3 years from the first appearance of symptoms. Older age and bulbar onset are consistently reported to have poorer outcomes. However, there are conflicting data regarding gender, diagnostic delay and El Escorial criteria. The rate of symptom progression has been revealed to be an independent prognostic factor. Psychosocial factors and impaired cognitive function are negatively related to ALS outcome, while nutritional status and respiratory function are also related to ALS prognosis. The effect of enteral nutrition on survival is still unclear, although noninvasive positive pressure ventilation (NIPPV) has been found to improve survival. These findings have relevant implications for the design of future trials.

[Epidemiology, clinical spectrum of ALS and differential diagnoses]

Amyotrophic Lateral Sclerosis (ALS) is the most common motor neuron disease in adults. Its incidence in France is estimated at 2.5 per 100,000 population and its prevalence between 5 and 8 per 100,000 inhabitants. Good prognostic factors are age of early onset, a longer time to diagnosis, initial damage to the spinal onset, early management of undernutrition and restrictive respiratory failure. The diagnosis of ALS is primarily clinical and is based on the evidence of involvement of the central motor neuron and peripheral neuron (NMP) in different territories or spinal or bulbar. The EMG confirms the achievement of NMP, shows the extension to clinically preserved areas and allows to exclude some differential diagnoses. The clinical spectrum of ALS is broad: conventional forms beginning brachial, lower limb or bulbar onsets, rarer forms to start breathing, pyramidal forms, forms with cognitive and behavioural impairment. In 5-10% of cases, ALS is familial. In 15% of cases, it is associated with frontotemporal degeneration rather than orbito-frontal type. The main differential diagnoses are guided by the clinic: combining pure motor neuropathy with or without conduction block, post-polio syndrome, cramp-fasciculation syndrome, myasthenia gravis, paraneoplastic syndromes, Sjögren syndrome, retroviral infections, some endocrine disorders, some metabolic diseases, genetic diseases (Kennedy and SMA) and inclusion body myositis.

The widening spectrum of C9ORF72-related disease; genotype/phenotype correlations and potential modifiers of clinical phenotype

The GGGGCC (G4C2) repeat expansion in C9ORF72 is the most common cause of familial amyotrophic lateral sclerosis (ALS), frontotemporal lobar dementia (FTLD) and ALS-FTLD, as well as contributing to sporadic forms of these diseases. Screening of large cohorts of ALS and FTLD cohorts has identified that C9ORF72-ALS is represented throughout the clinical spectrum of ALS phenotypes, though in comparison with other genetic subtypes, C9ORF72 carriers have a higher incidence of bulbar onset disease. In contrast, C9ORF72-FTLD is predominantly associated with behavioural variant FTD, which often presents with psychosis, most commonly in the form of hallucinations and delusions. However, C9ORF72 expansions are not restricted to these clinical phenotypes. There is a higher than expected incidence of parkinsonism in ALS patients with C9ORF72 expansions, and the G4C2 repeat has also been reported in other motor phenotypes, such as primary lateral sclerosis, progressive muscular atrophy, corticobasal syndrome and Huntington-like disorders. In addition, the expansion has been identified in non-motor phenotypes including Alzheimer's disease and Lewy body dementia. It is not currently understood what is the basis of the clinical variation seen with the G4C2 repeat expansion. One potential explanation is repeat length. Sizing of the expansion by Southern blotting has established that there is somatic heterogeneity, with different expansion lengths in different tissues, even within the brain. To date, no correlation with expansion size and clinical phenotype has been established in ALS, whilst in FTLD only repeat size in the cerebellum was found to correlate with disease duration. Somatic heterogeneity suggests there is a degree of instability within the repeat and evidence of anticipation has been reported with reducing age of onset in subsequent generations. This variability/instability in expansion length, along with its interactions with environmental and genetic modifiers, such as TMEM106B, may be the basis of the differing clinical phenotypes arising from the mutation.

Age at onset of amyotrophic lateral sclerosis in China

BACKGROUND

For patients with amyotrophic lateral sclerosis (ALS), age at onset is not only a key factor for diagnosis and prognosis, but also a clue for exploring pathogenesis. Reports based on results from a single medical center suggested that the mean age at onset of ALS in China was earlier than in other developed countries. A larger, multicenter-based study is needed to confirm this finding.

METHODS

A registry-based study of ALS was conducted at 10 ALS centers of the Chinese ALS Association from March 1, 2009 to August 31, 2009. The demographical and clinical features of patients with ALS were collected.

RESULTS

Data from a total of 455 patients with ALS were available for analysis. The mean age at onset for the entire cohort was 52.4 ± 12.1 years. The peak age at onset was in the 45- to 49-year-old age group for women and the 55- to 59-year-old age group for men. The age at onset for patients from Guangzhou (a southern region) was significantly earlier than it was for patients from Shanghai (an eastern region) (t = 2.270, P = 0.025).

CONCLUSIONS

This investigation confirmed the earlier age at onset of ALS in China as compared with other countries. Further population-based case-control investigations of genetic and environmental factors are needed to identify the potential risk factors for Chinese ALS patients.

Is hyperlipidemia correlated with longer survival in patients with amyotrophic lateral sclerosis?

Amyotrophic lateral sclerosis (ALS) is the most serious form of degenerative motor neuron disease in adults, whose relentless course leads to death within 2-5 years, generally due to respiratory failure. Apart from the age and site of onset, no other factors have consistently demonstrated to be related to the ALS outcome. The aim of the study was to investigate the influence of fasting serum lipid levels (cholesterol and triglycerides) and the body mass index (BMI) at the time of diagnosis on survival in ALS patients. The study included 82 patients with ALS residing in the Belgrade area who were diagnosed with ALS over a time period of 4 years (2006-2009). Survival was assessed by the Kaplan-Meier method. In this retrospective study, 39 (47.56%) patients had normal values of lipids and 43 (52.43%) patients had hyperlipidemia. The mean survival time from the onset of symptoms for patients with normal lipidemia was 4.21 ± 0.5 years, while the mean survival time from the onset of symptoms for patients with hyperlipidemia was 5.0 ± 0.67 years (P = 0.36). We also did not register a significant difference in survival in relation to gender, the site or age of onset, even though we noticed a longer survival in patients with hyperlipidemia in all of the examined groups, especially in the group of younger patients, with the onset of the disease before the age of 45 years. If we take into account the fact that BMI is pathophysiologically associated with cholesterol and triglyceride serum levels, the results in our study complement each other showing that patients with a higher BMI, registered in 28.8% of the cases, do not live longer. Our findings show that hyperlipidemia, which we found in 52.43% of our ALS patients, at the time of diagnosis, is not related to significantly longer survival.

Patients who survive 5 years or more with ALS in Olmsted County, 1925-2004

BACKGROUND

A small proportion of patients with amyotrophic lateral sclerosis (ALS) survive more than 5 years. The frequency of 5-year or longer survival with ALS in a USA population is unknown but may provide a baseline for studies that employ survival as a primary endpoint of analysis.

METHODS

All persons diagnosed as having ALS in Olmsted County between 1925 and 2004 were studied for demographic and clinical features. Longer-term survivors were defined as patients who lived 5 years or longer, tracheostomy-free, following symptomatic onset.

RESULTS

94 patients (mean survival from symptomatic onset 2.95 years (95% CI 2.54 to 3.35), mean survival from diagnosis 1.89 years (95% CI 1.54 to 2.24)) were diagnosed as having ALS. Five-year or longer survivors accounted for 14% of the population of patients (95% CI 7.9% to 22.8%). The frequency of 5 year or longer survivors did not change over time. The mean survival of these individuals was 7.04 years (95% CI 6.14 to 7.94 years; range 5.11-9.35 years). They had a significantly longer mean time to diagnosis (1.77 years, 95% CI 0.95 to 2.58 years) as compared with survivors of less than 5 years (0.94 years, 95% CI 0.75 to 1.13 years) (p=0.02) but could not be reliably identified at the time of diagnosis by age, sex, clinical presentation or El Escorial category.

CONCLUSION

Patients surviving more than 5 years following the symptomatic onset of ALS account for 14% of the total ALS population. This frequency has not changed over time. Patients with a survival of 5 years or longer are clinically similar to the total population ALS population in terms of age, gender, presentation and site of onset but have a longer time from symptomatic onset to diagnosis. GRANT NUMBER: NIH AR30582.

Prognosis of ALS: comparing data from the Limousin referral centre, France, and a Uruguayan population

Our objective was to compare clinical features and survival in two groups of ALS patients from countries in opposite hemispheres. The study took place at an ALS referral centre in the Limousin region of France (LIM) and in Uruguay (UY). All consecutive patients diagnosed with ALS between 1 January 2002 and 31 December 2004 were enrolled. Data from a total of 187 ALS patients were analysed: 84 from LIM and 103 from UY. Mean ages at onset and diagnosis were significantly higher in LIM (66 vs. 61 years). UY patients demonstrated more advanced disease at the time of diagnosis. The proportions of definite forms were 82% in UY versus 10% in LIM (p<0.001), and median manual muscle testing (MMT) and ALSFRS scores were significantly lower in LIM. This observed difference was not directly explained by a longer diagnostic delay in UY (10 vs. 9 months). Median survival from time of diagnosis was significantly shorter in UY patients (19 vs. 28 months; log-rank test, p=0.030). In conclusion, survival of ALS patients in UY is nine months shorter than in LIM, probably due to the heterogeneity of medical care and the absence of an ALS referral centre.

Incidence of amyotrophic lateral sclerosis in the Limousin region of France, 1997-2007

Our objective was to assess the incidence of amyotrophic lateral sclerosis (ALS), and its temporal variations, between 1997 and 2007. The study was based on data prospectively gathered by the referral ALS 'expert centre' of the Regional University Hospital of Limousin (710,792 inhabitants). Patients were included if they were diagnosed with ALS according to the revised El Escorial criteria either at the time of diagnosis or at subsequent follow-up, and if they resided in Limousin when diagnosed. We identified a high crude incidence (2.5/100,000). When age-standardized for the 1999 French population, the mean annual incidence was 2.0/100,000 inhabitants (95% CI 1.8-2.3) overall and 4.4 (95% CI 3.6-5.2) in the 45-74 years age group. Crude incidence by age groups showed a progressive increase up to 85 years, followed by a sharp decrease thereafter. Age at diagnosis was particularly high in our population (median, 69.4 years). Incidence of ALS in Limousin was consistent with previous work published by European population-based registries. The atypical epidemiology was explained in part by Limousin's older aged population. It is proposed that our referral centre will become a population-based registry.

Prognostic factors in ALS: A critical review

We have performed a systematic review to summarize current knowledge concerning factors related to survival in ALS and to evaluate the implications of these data for clinical trials design. The median survival time from onset to death ranges from 20 to 48 months, but 10-20% of ALS patients have a survival longer than 10 years. Older age and bulbar onset are consistently reported to have a worse outcome. There are conflicting data on gender, diagnostic delay and El Escorial criteria. The rate of symptom progression was revealed to be an independent prognostic factor. Psychosocial factors, FTD, nutritional status, and respiratory function are also related to ALS outcome. The effect of enteral nutrition on survival is still unclear, while NIPPV has been found to improve survival. There are no well established biological markers of progression, although some are likely to emerge in the near future. These findings have relevant implications for the design of future trials. Randomization, besides the type of onset, should take into account age, respiratory status at entry, and a measure of disease progression pre-entry. Alternative trial designs can include the use of natural history controls, the so-called minimization method for treatment allocation, and the futility approach.

Amyotrophic lateral sclerosis: Prognostic indicators of survival

Amyotrophic lateral sclerosis (ALS) has a fatal outcome in about three years, but survival is known to vary considerably, making it difficult to predict disease duration in individual cases. The aim of this study was to investigate possible early prognostic factors of ALS survival. We included 123 probable or definite cases of ALS, with disease onset between 1989 and 1998, and with a follow-up of at least one year. Survival functions were obtained using both the Kaplan-Meier and the actuarial methods. Subgroups, formed on the basis of gender, area of residence, work, and age at and site of onset, were compared using the logrank test and Cox's proportional hazards method (survival functions), and applying the Grizzle, Starmer, Koch (1969), and Koch, Johnson, Tolley (1972) methods (one-year survival probability trends). The survival curves dipped sharply in the first three years, followed by a flattening trend, with 50% of patients dying within 2.5 years, and 89% over seven years. The clinical form with lower limb onset was associated with longer survival than the upper limb onset and bulbar forms (median survival: 39, 27, and 25 months, respectively). Survival was also affected by age at onset (median survival: 34, 27, and 23 months for onset <60, 60-75, and >75 years, respectively), area of residence (median survival: 24 months in mountainous areas, 32 elsewhere), and type of work (median survival: 25 months in agricultural workers, 33.5 in others). Gender did not influence survival, whereas percutaneous endoscopic gastrostomy placement and invasive ventilation did. The estimation of individual ALS survival is important to allow the patient to plan for his future and to make optimal use of medical and community resources. Although age at and site of onset, area of residence, and agricultural work were found to influence survival, there remains an unexplained heterogeneous progression of the disease, suggesting the influence of other, as yet unknown, prognostic factors. The identification of a definite set of prognostic factors may allow physicians to make more reliable survival predictions at diagnosis.

SEROTONERGIC MECHANISMS IN AMYOTROPHIC LATERAL SCLEROSIS

Serotonin (5-HT) has been intimately linked with global regulation of motor behavior, local control of motoneuron excitability, functional recovery of spinal motoneurons as well as neuronal maturation and aging. Selective degeneration of motoneurons is the pathological hallmark of amyotrophic lateral sclerosis (ALS). Motoneurons that are preferentially affected in ALS are also densely innervated by 5-HT neurons (e.g., trigeminal, facial, ambiguus, and hypoglossal brainstem nuclei as well as ventral horn and motor cortex). Conversely, motoneuron groups that appear more resistant to the process of neurodegeneration in ALS (e.g., oculomotor, trochlear, and abducens nuclei) as well as the cerebellum receive only sparse 5-HT input. The glutamate excitotoxicity theory maintains that in ALS degeneration of motoneurons is caused by excessive glutamate neurotransmission, which is neurotoxic. Because of its facilitatory effects on glutaminergic motoneuron excitation, 5-HT may be pivotal to the pathogenesis and therapy of ALS. 5-HT levels as well as the concentrations 5-hydroxyindole acetic acid (5-HIAA), the major metabolite of 5-HT, are reduced in postmortem spinal cord tissue of ALS patients indicating decreased 5-HT release. Furthermore, cerebrospinal fluid levels of tryptophan, a precursor of 5-HT, are decreased in patients with ALS and plasma concentrations of tryptophan are also decreased with the lowest levels found in the most severely affected patients. In ALS progressive degeneration of 5-HT neurons would result in a compensatory increase in glutamate excitation of motoneurons. Additionally, because 5-HT, acting through presynaptic 5-HT1B receptors, inhibits glutamatergic synaptic transmission, lowered 5-HT activity would lead to increased synaptic glutamate release. Furthermore, 5-HT is a precursor of melatonin, which inhibits glutamate release and glutamate-induced neurotoxicity. Thus, progressive degeneration of 5-HT neurons affecting motoneuron activity constitutes the prime mover of the disease and its progression and treatment of ALS needs to be focused primarily on boosting 5-HT functions (e.g., pharmacologically via its precursors, reuptake inhibitors, selective 5-HT1A receptor agonists/5-HT2 receptor antagonists, and electrically through transcranial administration of AC pulsed picotesla electromagnetic fields) to prevent excessive glutamate activity in the motoneurons. In fact, 5HT1A and 5HT2 receptor agonists have been shown to prevent glutamate-induced neurotoxicity in primary cortical cell cultures and the 5-HT precursor 5-hydroxytryptophan (5-HTP) improved locomotor function and survival of transgenic SOD1 G93A mice, an animal model of ALS.

Amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterised by progressive muscular paralysis reflecting degeneration of motor neurones in the primary motor cortex, corticospinal tracts, brainstem and spinal cord. Incidence (average 1.89 per 100,000/year) and prevalence (average 5.2 per 100,000) are relatively uniform in Western countries, although foci of higher frequency occur in the Western Pacific. The mean age of onset for sporadic ALS is about 60 years. Overall, there is a slight male prevalence (M:F ratio approximately 1.5:1). Approximately two thirds of patients with typical ALS have a spinal form of the disease (limb onset) and present with symptoms related to focal muscle weakness and wasting, where the symptoms may start either distally or proximally in the upper and lower limbs. Gradually, spasticity may develop in the weakened atrophic limbs, affecting manual dexterity and gait. Patients with bulbar onset ALS usually present with dysarthria and dysphagia for solid or liquids, and limbs symptoms can develop almost simultaneously with bulbar symptoms, and in the vast majority of cases will occur within 1-2 years. Paralysis is progressive and leads to death due to respiratory failure within 2-3 years for bulbar onset cases and 3-5 years for limb onset ALS cases. Most ALS cases are sporadic but 5-10% of cases are familial, and of these 20% have a mutation of the SOD1 gene and about 2-5% have mutations of the TARDBP (TDP-43) gene. Two percent of apparently sporadic patients have SOD1 mutations, and TARDBP mutations also occur in sporadic cases. The diagnosis is based on clinical history, examination, electromyography, and exclusion of 'ALS-mimics' (e.g. cervical spondylotic myelopathies, multifocal motor neuropathy, Kennedy's disease) by appropriate investigations. The pathological hallmarks comprise loss of motor neurones with intraneuronal ubiquitin-immunoreactive inclusions in upper motor neurones and TDP-43 immunoreactive inclusions in degenerating lower motor neurones. Signs of upper motor neurone and lower motor neurone damage not explained by any other disease process are suggestive of ALS. The management of ALS is supportive, palliative, and multidisciplinary. Non-invasive ventilation prolongs survival and improves quality of life. Riluzole is the only drug that has been shown to extend survival.

Outcome measures and prognostic indicators in patients with amyotrophic lateral sclerosis

The purpose of the study was to assess frequency and predictors of disability measures in ALS. One hundred and fourteen newly diagnosed patients resident in eight administrative districts of Lombardy, Italy (population 4,947,554), included in a population-based registry, were followed for 2570 person-months (mean 22.5 months). The cumulative time-dependent risk of wheelchair, percutaneous endoscopic gastrostomy, and assisted ventilation was estimated according to the Kaplan-Meier method. Predictors of disability (age, sex, disease duration at diagnosis, type of onset, El-Escorial diagnosis) were assessed with the Cox proportional hazard function. During follow-up, 29 patients (25.4%) became wheelchair bound, 51 (44.7%) received gastrostomy, and 47 (41.2%) received assisted ventilation. The median time to loss of ambulation was 46.7 months (95% CI 36.5-56.8). The median time to gastrostomy and assisted ventilation was 31.1 months (95% CI 26.8-35.4) and 34.6 months (95% CI 29.6-39.6), respectively. Spinal onset ALS was the only predictor of loss of ambulation. Predictors of gastrostomy were older age, definite ALS, and shorter disease duration. Shorter disease duration was the only predictor of assisted ventilation. In conclusion, patients with ALS differ in terms of measures and predictors of disability. These factors are sources of bias and confounding in randomized clinical trials.

Disease progression and survival in ALS: first multi-state model approach

Although several prognostic factors have been identified in ALS, there remains some discordance concerning the prognostic significance of the age and clinical form at onset. In order to clarify these findings, we have analysed already known prognostic factors using a multi-state model. Two hundred and twenty-two sporadic ALS patients were followed. A simple unidirectional three-states model was used to summarize clinical course of ALS. States 1 and 2 reflected the progression of neurological impairment and state 3 represented the end of follow-up (tracheotomy or death). Gender, diagnostic delay, body mass index (BMI) and slow vital capacity (SVC) were also recorded. A time-inhomogeneous Markov model with piecewise constant transition intensities was used to estimate the effect of the covariates in each transition. The bulbar form at onset was only correlated with a more rapid clinical progression between state 1 and state 2. In contrast, an advanced age at diagnosis affected only survival from state 2. This methodological approach suggests that these two factors have a different prognostic significance: age at onset is related to patient's survival and the clinical form at onset predicts the progression of motoneuronal impairment in different regions.

Predictability of disease progression in amyotrophic lateral sclerosis

The aim of this study was to determine the predictors of disease progression in a group of 832 patients with the diagnosis of definite or probable amyotrophic lateral sclerosis (ALS). Disease progression was defined as the time to 20-point change in Appel ALS (AALS) score. The effects of individual prognostic factors on disease progression were assessed with the Kaplan-Meier life-table method. In addition, the prognostic value of each factor was estimated using both univariate and multivariate Cox proportional hazard analyses. The median time to a 20-point change in AALS score in our patient population was 9 months. Age, site of symptom onset, time between first symptom and first examination, total AALS score at first examination, and AALS preslope (rate of disease progression between first symptom and first examination) were significant and independent covariates of disease progression in our population. Identification of predictors of disease progression will facilitate better design of therapeutic trials, permitting the use of disease progression as a primary endpoint and improving baseline stratification of patient populations.

Chemokine MIP-2/CXCL2, acting on CXCR2, induces motor neuron death in primary cultures

OBJECTIVES

Chemokines are implicated in many diseases of the central nervous system (CNS). Although their primary role is to induce inflammation through the recruitment of leukocytes by their chemotactic activity, they may also have direct effects on neuronal cells. We evaluated the expression of CXCR1 and CXCR2 and investigated the effect of CXCR2 activation by the agonist MIP-2 (CXCL2) on primary cultured motor neurons. To specifically assess the role of CXCR2 in the neurotoxicity induced by MIP-2, we used the CXCR1/2 inhibitor reparixin and studied the effect of the chemokine on motor neuron cultures from CXCR2-deficient mice.

METHODS

Primary motor neurons prepared from rat or mouse embryos were treated with MIP-2 and reparixin. Motor neuron viability and receptor expression were assessed by immunocytochemical techniques.

RESULTS

Rat primary motor neurons expressed CXCR2 receptors and recombinant rat MIP-2 induced dose-dependent neurotoxicity. This neurotoxicity was counteracted by reparixin, a specific CXCR1/2 inhibitor, and was not observed in motor neurons from CXCR2-deficient mice.

CONCLUSIONS

CXCR2 activation might directly contribute to motor neuron degeneration. Thus, chemokines acting on CXCR2, including IL-8, may have direct pathogenic effects in CNS diseases, independent of the induction of leukocyte migration.

Amyotrophic lateral sclerosis: early predictors of prolonged survival

OBJECTIVE

In order to define the predictors of prolonged survival available at the time of first examination we performed a historical cohort study of amyotrophis sclerosis (ALS) patients referred to our ALS Clinic over the last 20 years.

METHODS

In a group of 1034 patients with the diagnosis of definite or probable ALS the effects of individual prognostic factors on tracheostomy-free survival were assessed with the Kaplan-Meier life-table method. The prognostic value of each factor was estimated using univariate and multivariate Cox proportional hazard analyses.

RESULTS

The median survival time was 3.45 years, (95%CI 3.27-3.74). Both the univariate and multivariate Cox models indicated that younger age, limb site of onset, longer diagnostic delay, lower Appel ALS score (AALSS) at first examination, lower AALSS-rate of change between first symptom and first exam (preslope), and higher baseline forced vital capacity (FVC) were associated with longer survival. In addition, four factors: age, diagnostic delay, baseline FVC and AALSS preslope have been identified as independent predictors of survival in our patient population.

CONCLUSIONS

The identification of younger age, limb site of onset and longer diagnostic delay as predictors of prolonged survival in ALS clinic population supports the findings of several, earlier studies that were based on smaller groups of patients. More significantly, several additional variables assessed at the first examination predict longer survival: lower baseline AALSS, lower AALSS- preslope and higher baseline FVC. All of these parameters are of value in patient management and in clinical trial development.

Effects of non-invasive ventilation on survival and quality of life in patients with amyotrophic lateral sclerosis: a randomised controlled trial

BACKGROUND

Few patients with amyotrophic lateral sclerosis currently receive non-invasive ventilation (NIV), reflecting clinical uncertainty about the role of this intervention. We aimed to assess the effect of NIV on quality of life and survival in amyotrophic lateral sclerosis in a randomised controlled trial.

METHODS

92 of 102 eligible patients participated. They were assessed every 2 months and randomly assigned to NIV (n=22) or standard care (n=19) when they developed either orthopnoea with maximum inspiratory pressure less than 60% of that predicted or symptomatic hypercapnia. Primary validated quality-of-life outcome measures were the short form 36 mental component summary (MCS) and the sleep apnoea quality-of-life index symptoms domain (sym). Both time maintained above 75% of baseline (T(i)MCS and T(i)sym) and mean improvement (microMCS and microsym) were measured.

FINDINGS

NIV improved T(i)MCS, T(i)sym, microMCS, microsym, and survival in all patients and in the subgroup with better bulbar function (n=20). This subgroup showed improvement in several measures of quality of life and a median survival benefit of 205 days (p=0.006) with maintained quality of life for most of this period. NIV improved some quality-of-life indices in those with poor bulbar function, including microsym (p=0.018), but conferred no survival benefit.

INTERPRETATION

In patients with amyotrophic lateral sclerosis without severe bulbar dysfunction, NIV improves survival with maintenance of, and improvement in, quality of life. The survival benefit from NIV in this group is much greater than that from currently available neuroprotective therapy. In patients with severe bulbar impairment, NIV improves sleep-related symptoms, but is unlikely to confer a large survival advantage.

Clinical Trials in ALS: What Did We Learn from Recent Trials in Humans?

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease. No treatment is currently able to stop the disease process. In the absence of new active compounds there is an urgent need to develop new strategies based on the neuroprotective activity of available drugs. ALS is a heterogeneous disease. To build up these therapeutic trials, we need to have a better understanding of the prognostic factors in this disease. During the Phase IV Rilutek Trial in France, we developed in a large population of patients a prognostic score based on clinical parameters available at the bedside. The most significant variables are vital capacity, spasticity, fasciculations, swallowing, cough and creatininemia. This score proved to be very useful in daily use in the clinic and for planning disease management in ALS as in the design of therapeutic trials. In ALS clinical trials, efficacy can be evaluated using survival or functional parameters. In phase II trials, function remains the most commonly used. In phase III trials, the gold standard endpoint remains the survival rate at month 18. We analyzed the most recent ALS trials published in the literature. This review suggests that in these trials there is a discrepancy between drug effects on survival versus function. These results suggest that a reappraisal of strategies to identify therapeutic targets for ALS is required.

Survival of Patients with Amyotrophic Lateral Sclerosis in a Population-Based Registry

OBJECTIVE

To evaluate the survival of patients with amyotrophic lateral sclerosis (ALS) in an Italian population and to assess the effects of selected prognostic indicators on survival.

BACKGROUND

Median survival of ALS patients has been reported to range between 12 and 23 months from diagnosis and between 23 and 36 months from onset of symptoms. Although several negative prognostic factors have been identified, the overall picture still needs clarification.

METHODS

We included patients enrolled in an Italian ALS Regional Register (population 4,529,003) during the calendar year 1998. The diagnosis was confirmed by an ad hoc committee using the original El Escorial criteria. Each case was regularly followed up until death or December 31, 2002, whichever came first. Survival was assessed with the Kaplan-Meier method in the whole sample, by level of diagnostic certainty, and by selected prognostic indicators (age, sex, bulbar or spinal onset, and disease duration). Multivariate analysis was done with the Cox proportional hazard function.

RESULTS

The sample comprised 79 patients (33 female; 46 male) aged 28-85 years (mean age 64.4 years). Onset of symptoms was bulbar in 30% of cases. Mean symptom duration at diagnosis was 13.3 months. ALS was definite in 43%, probable in 29%, possible in 6%, and suspected in 22%. By December 31, 2002, 56 cases (71%) had died. The cumulative probability of surviving after diagnosis was 78% at 12 months, 56% at 24 months, and 32% at 48 months. Median survival from onset was 39.2 months and from diagnosis 30.6 months. Multivariate analysis confirmed definite ALS at diagnosis and older age as adverse prognostic factors.

CONCLUSIONS

Survival of ALS patients in the present sample was slightly longer than previously reported. Better palliative care and supportive treatment may explain the difference. Older age and the presence of definite ALS at diagnosis are poor prognostic predictors.

Patterns of mortality in patients with motor neurone disease

OBJECTIVE

Motor neurone disease (MND) is a rapidly fatal condition with survival of less than 4 years. Patients can deteriorate quickly in the preterminal stages resulting in inappropriate resuscitation or admission to intensive care units (ICU) or accident and emergency (A & E).

MATERIAL AND METHODS

We looked at patterns of mortality with emphasis on the place of death. A retrospective study was performed of all patients attending an MND clinic, who had died within a 10-year period.

RESULTS

Of 179 patients (63 female), 81 patients (45%) died at home, in a hospice or in a nursing home. Sixty-five patients (36%) died in hospital (11 in ICU or A & E). Nine of the latter were previously known to have MND and six admissions were probably avoidable. Most ward patients died of respiratory causes and were treated conservatively.

CONCLUSION

The proportion of patients dying in A & E or ICU was small but could have been reduced further. A number of those who died on the wards could probably have been managed conservatively at home. Older patients and those with bulbar disease had a poorer prognosis.

Disease progression in amyotrophic lateral sclerosis: predictors of survival

Predicting the rate of disease progression has become important as trials of new medical treatments for amyotrophic lateral sclerosis (ALS) are planned. Bulbar onset, early impairment of forced vital capacity, and older age have all been associated with shorter survival. We performed a retrospective study to compare survival factors with disease progression in a German ALS population. We analyzed disease progression in 155 patients at intervals of 4 months over a period of 3 years. To evaluate disease progression, the ALS functional rating scale (ALS-FRS), forced vital capacity (FVC%), and a Medical Research Council (MRC) compound score based on a nine-step modified MRC scale were used. We compared age (< 55 years vs. > or =55 years), different sites of disease onset (bulbar vs. limb), and gender to the rate of disease progression and performed survival analyses. No overall significant difference could be detected when analyzing these subgroups with regard to disease progression. By contrast, significantly longer survival was observed in the younger age group (56 months vs. 38 months, P < 0.0001) and in patients with limb-onset disease (51 months vs. 37 months, P = 0.0002). Using Cox analyses values we found that the declines of ALS-FRS, FVC%, and MRC compound score were predictive of survival (P < 0.0001, P = 0.002, and P = 0.003, respectively). Future studies are needed to clarify whether nonspecific factors including muscle atrophy, dysphagia, and coexisting diseases influence prediction of survival in ALS patients. A more precise set of predictors may help to better stratify patient subgroups for future treatment trials.

Estimation of the amyotrophic lateral sclerosis incidence by capture-recapture method in the Limousin region of France

Amyotrophic lateral sclerosis (ALS) is a rapidly fatal degenerative neurological disease categorized among motor neuron diseases. In the literature, the incidence of ALS varies between 0.7 and 2.4 per 100, 000 inhabitants. A study using the capture-recapture method (multiple records system analysis) was undertaken in Limousin (France) ascertaining all patients having onset of definite or probable ALS during the period 1994-1995. Three information sources able to identify these new ALS cases were selected: the first source was a computerized database of the Neurology Department of the University Hospital of Limoges; the second source consisted of the neurologists of the Limousin region and neighboring provinces (county-sized regions); the third source grouped the hospitals of the Limousin region and neighboring provinces (county-sized regions). During this period, 46 new cases of ALS were seen, corresponding to an observed mean annual incidence of 3.2 (+/-0.6) per 100,000 inhabitants. After standardization for age, the annual incidence was 2.5 per 100,000 inhabitants. The number of new cases estimated by the capture-recapture method was 70, corresponding to an estimated mean annual incidence of 4.9 (+/-1.0) for 100,000 inhabitants. Hence, statistical modeling utilizing partially overlapping information sources permitted a more exhaustive compendium of the new cases of ALS and may be a truer reflection of actual disease incidence than has been previously reported.

Consensus guidelines for the design and implementation of clinical trials in ALS. World Federation of Neurology committee on Research

BACKGROUND

In 1994 consensus guidelines were developed for conducting clinical trials in ALS. With growing experience in clinical trials, it has become clear that a number of further guidelines were needed.

METHODS

Under the auspices of the World Federation of Neurology Committee on Research, a multinational group of neurologists, statisticians, patient advocates, representatives from the pharmaceutical industry as well as regulatory agencies developed consensus about a number of revisions to the existing guidelines during a 2 day conference in April 1998.

RESULTS

Expanded areas of focus include greater protection of patient rights, more detailed guidelines for outcome measures statistical analyses, disclosure of study results and improved interaction between investigators and the corporate sector.

COMMENT

Substantial progress has been made in standardizing and improving the quality of clinical trials in ALS through these consensus guidelines.

Temporary amelioration of symptoms with intravenous cyclophosphamide in amyotrophic lateral sclerosis

Based on the evidence that autoimmunity may play a role in the pathogenesis of amyotrophic lateral sclerosis (ALS), a variety of immunomodulating agents have been used in the treatment. In an uncontrolled trial we treated 44 patients of ALS with intravenous cyclophosphamide (IVCP) at a total dose of 1.5 g/m2 given over a period of 8 to 10 days. The patients were evaluated using neurological score which included bulbar, motor and daily activity scores before and following treatment. Twenty three patients showed a significant improvement (P=<0.001) in the composite and the individual scores. The improvement persisted only for 2 to 3 months. Amongst them the severely (7) and moderately (16) affected (score less than or more than 150) showed almost a similar response to treatment. A comparison of the improved group of 23 patients with the unimproved group of 21 patients did not reveal any significant factors which influenced the response to IVCP. However, there was a suggestion that patients below the age of 60 years and a duration of illness less than 12 months may respond to the drug. In conclusion, treatment with intravenous cyclophosphamide resulted in mild and temporary improvement in clinical status of the patients with amyotrophic lateral sclerosis. This may be considered as an alternative method of treatment in developing countries where newer drugs are not available and affordable.