Clinical correlations and long-term follow-up in 100 patients with sarcoglycanopathies.

BACKGROUND AND PURPOSE: To describe a large series of patients with α, ß, and γ sarcoglycanopathies (LGMD-R3, R4, and R5) and study phenotypic correlations and disease progression. METHODS: A multicentric retrospective study in four centers in the Paris area collecting neuromuscular, respiratory, cardiac, histologic, and genetic data. The primary outcome of progression was age of loss of ambulation (LoA); disease severity was established according to LoA before or after 18 years of age. Time-to-event analysis was performed. RESULTS: One hundred patients (54 γ-SG; 41 α-SG; 5 ß-SG) from 80 families were included. The γ-SG patients had earlier disease onset than α-SG patients (5.5 vs. 8 years; p = 0.022) and ß-SG patients (24.4 years). Axial muscle weakness and joint contractures were frequent and exercise intolerance was observed. At mean follow-up of 22.9 years, 65.3% of patients were wheelchair-bound (66.7% α-SG, 67.3% γ-SG, 40% ß-SG). Dilated cardiomyopathy occurred in all sarcoglycanopathy subtypes, especially in γ-SG patients (p = 0.01). Thirty patients were ventilated and six died. Absent sarcoglycan protein expression on muscle biopsy and younger age at onset were associated with earlier time to LoA (p = 0.021 and p = 0.002). Age at onset was an independent predictor of both severity and time to LoA (p = 0.0004 and p = 0.009). The α-SG patients showed genetic heterogeneity, whereas >90% of γ-SG patients carried the homozygous c.525delT frameshift variant. Five new mutations were identified. CONCLUSIONS: This large multicentric series delineates the clinical spectrum of patients with sarcoglycanopathies. Age at disease onset is an independent predictor of severity of disease and LoA, and should be taken into account in future clinical trials.

Adaptive functional reorganization in amyotrophic lateral sclerosis: coexisting degenerative and compensatory changes.

BACKGROUND AND PURPOSE: Considerable functional reorganization takes place in amyotrophic lateral sclerosis (ALS) in face of relentless structural degeneration. This study evaluates functional adaptation in ALS patients with lower motor neuron predominant (LMNp) and upper motor neuron predominant (UMNp) dysfunction. METHODS: Seventeen LMNp ALS patients, 14 UMNp ALS patients and 14 controls participated in a functional magnetic resonance imaging study. Study-group-specific activation patterns were evaluated during preparation for a motor task. Connectivity analyses were carried out using the supplementary motor area (SMA), cerebellum and striatum as seed regions and correlations were explored with clinical measures. RESULTS: Increased cerebellar, decreased dorsolateral prefrontal cortex and decreased SMA activation were detected in UMNp patients compared to controls. Increased cerebellar activation was also detected in UMNp patients compared to LMNp patients. UMNp patients exhibit increased effective connectivity between the cerebellum and caudate, and decreased connectivity between the SMA and caudate and between the SMA and cerebellum when performing self-initiated movement. In UMNp patients, a positive correlation was detected between clinical variables and striato-cerebellar connectivity. CONCLUSIONS: Our findings indicate that, despite the dysfunction of SMA-striatal and SMA-cerebellar networks, cerebello-striatal connectivity increases in ALS indicative of compensatory processes. The coexistence of circuits with decreased and increased connectivity suggests concomitant neurodegenerative and adaptive changes in ALS.

Insights into the genetic epidemiology of spinal and bulbar muscular atrophy: prevalence estimation and multiple founder haplotypes in the Veneto Italian region.

BACKGROUND AND PURPOSE: Literature data on spinal and bulbar muscular atrophy (SBMA) epidemiology are limited and restricted to specific populations. The aim of our study was to accurately collect information about SBMA patients living in the Veneto region in Italy to compute reliable epidemiological data. Androgen receptor (AR) lineages were genotyped to evaluate the presence of a founder effect. METHODS: A prevalence survey considering all SBMA patients diagnosed in the Italian Veneto region on 31 January 2018 was carried out. The presence of different haplotypes obtained genotyping 15 polymorphic markers (single nucleotide polymorphisms and short tandem repeats) around the AR gene was evaluated. RESULTS: Based on 68 patients, the punctual prevalence of the disease on 31 January 2018 was 2.58/100 000 (95% confidence interval 1.65-3.35) in the male population. Five different haplotypes were identified, confirming the existence of multiple founder effects. It was also observed that, within the same haplotype, patients had a similar CAG repeat number (P-value < 0.001). CONCLUSIONS: A reliable estimation of SBMA prevalence in the Italian Veneto region was calculated which does not seem to be affected by a strong founder effect. Moreover, our data suggest that the length of the CAG expansion could be preserved in patients harbouring the same haplotype.

Cardiovascular diseases may play a negative role in the prognosis of amyotrophic lateral sclerosis.

BACKGROUND AND PURPOSE: Only a few studies have considered the role of comorbidities in the prognosis of amyotrophic lateral sclerosis (ALS) and have provided conflicting results. METHODS: Our multicentre, retrospective study included patients diagnosed from 1 January 2009 to 31 December 2013 in 13 referral centres for ALS located in 10 Italian regions. Neurologists at these centres collected a detailed phenotypic profile and follow-up data until death in an electronic database. Comorbidities at diagnosis were recorded by main categories and single medical diagnosis, with the aim of investigating their role in ALS prognosis. RESULTS: A total of 2354 incident cases were collected, with a median survival time from onset to death/tracheostomy of 43 months. According to univariate analysis, together with well-known clinical prognostic factors (age at onset, diagnostic delay, site of onset, phenotype, Revised El Escorial Criteria and body mass index at diagnosis), the presence of dementia, hypertension, heart disease, chronic obstructive pulmonary disease, haematological and psychiatric diseases was associated with worse survival. In multivariate analysis, age at onset, diagnostic delay, phenotypes, body mass index at diagnosis, Revised El Escorial Criteria, dementia, hypertension, heart diseases (atrial fibrillation and heart failure) and haematological diseases (disorders of thrombosis and haemostasis) were independent prognostic factors of survival in ALS. CONCLUSIONS: Our large, multicentre study demonstrated that, together with the known clinical factors that are known to be prognostic for ALS survival, hypertension and heart diseases (i.e. atrial fibrillation and heart failure) as well as haematological diseases are independently associated with a shorter survival. Our findings suggest some mechanisms that are possibly involved in disease progression, giving new interesting clues that may be of value for clinical practice and ALS comorbidity management.

Spinal cord multi-parametric magnetic resonance imaging for survival prediction in amyotrophic lateral sclerosis.

BACKGROUND AND PURPOSE: Assessing survival is a critical issue in patients with amyotrophic lateral sclerosis (ALS). Neuroimaging seems to be promising in the assessment of disease severity and several studies also suggest a strong relationship between spinal cord (SC) atrophy described by magnetic resonance imaging (MRI) and disease progression. The aim of the study was to determine the predictive added value of multimodal SC MRI on survival. METHODS: Forty-nine ALS patients were recruited and clinical data were collected. Patients were scored on the Revised ALS Functional Rating Scale and manual muscle testing. They were followed longitudinally to assess survival. The cervical SC was imaged using the 3 T MRI system. Cord volume and cross-sectional area (CSA) at each vertebral level were computed. Diffusion tensor imaging metrics were measured. Imaging metrics and clinical variables were used as inputs for a multivariate Cox regression survival model. RESULTS: On building a multivariate Cox regression model with clinical and MRI parameters, fractional anisotropy, magnetization transfer ratio and CSA at C2-C3, C4-C5, C5-C6 and C6-C7 vertebral levels were significant. Moreover, the hazard ratio calculated for CSA at the C3-C4 and C5-C6 levels indicated an increased risk for patients with SC atrophy (respectively 0.66 and 0.68). In our cohort, MRI parameters seem to be more predictive than clinical variables, which had a hazard ratio very close to 1. CONCLUSIONS: It is suggested that multimodal SC MRI could be a useful tool in survival prediction especially if used at the beginning of the disease and when combined with clinical variables. To validate it as a biomarker, confirmation of the results in bigger independent cohorts of patients is warranted.

Kennedy disease (X-linked recessive bulbospinal neuronopathy): A comprehensive review from pathophysiology to therapy.

Kennedy's disease, also known as spinal and bulbar muscular atrophy (SBMA), is a rare, adult-onset, X-linked recessive neuromuscular disease caused by expansion of a CAG repeat sequence in exon 1 of the androgen receptor gene (AR) encoding a polyglutamine (polyQ) tract. The polyQ-expanded AR accumulates in nuclei, and initiates degeneration and loss of motor neurons and dorsal root ganglia. While the disease has long been considered a pure lower motor neuron disease, recently, the presence of major hyper-creatine-kinase (CK)-emia and myopathic alterations on muscle biopsy has suggested the presence of a primary myopathy underlying a wide range of clinical manifestations. The disease, which affects male adults, is characterized by muscle weakness and atrophy localized proximally in the limbs, and bulbar involvement. Sensory disturbances are associated with the motor phenotype, but may be subclinical. The most frequent systemic symptom is gynecomastia related to androgen insensitivity, but other abnormalities, such as heart rhythm and urinary disturbances, have also been reported. The course of the disease is slowly progressive with normal life expectancy. The diagnosis of SBMA is based on genetic testing, with 38 CAG repeats taken as pathogenic. Despite several therapeutic attempts made in mouse models, no effective disease-modifying therapy is yet available, although symptomatic therapy is beneficial for the management of the weakness, fatigue and bulbar symptoms.

No effect of AR polyG polymorphism on spinal and bulbar muscular atrophy phenotype.

BACKGROUND AND PURPOSE: Disease severity varies considerably among patients with Spinal and Bulbar Muscular Atrophy (SBMA). Our aim was to investigate the role of androgen receptor (AR) polymorphic repeats in SBMA phenotype. METHODS: We analyzed the length of AR polyQ and polyG tracts in 159 SBMA patients. RESULTS: No relationship between polyG size or polyG/polyQ haplotypes and clinical phenotype was found. An independent negative correlation between polyQ-length and onset of weakness was confirmed (P < 0.001). CONCLUSIONS: The negative results of our study prompt to continue the search for potential disease modifiers in SBMA outside the AR gene.

Quantitative brainstem and spinal MRI in amyotrophic lateral sclerosis: implications for predicting noninvasive ventilation needs.

BACKGROUND: Respiratory complications resulting from motor neurons degeneration are the primary cause of death in amyotrophic lateral sclerosis (ALS). Predicting the need for non-invasive ventilation (NIV) in ALS is important for advance care planning and clinical trial design. The aim of this study was to assess the potential of quantitative MRI at the brainstem and spinal cord levels to predict the need for NIV during the first six months after diagnosis. METHODS: Forty-one ALS patients underwent MRI and spirometry shortly after diagnosis. The need for NIV was monitored according to French health guidelines for 6 months. The performance of four regression models based on: clinical variables, brainstem structures volumes, cervical spinal measurements, and combined variables were compared to predict the need for NIV within this period. RESULTS: Both the clinical model (R2 = 0.28, AUC = 0.85, AICc = 42.67, BIC = 49.8) and the brainstem structures' volumes model (R2 = 0.30, AUC = 0.85, AICc = 40.13, BIC = 46.99) demonstrated good predictive performance. In addition, cervical spinal cord measurements model similar performance (R2 = 0.338, AUC = 0.87, AICc = 37.99, BIC = 44.49). Notably, the combined model incorporating predictors from all three models yielded the best performance (R2 = 0.60, AUC = 0.959, AICc = 36.38, BIC = 44.8). These findings are supported by observed positive correlations between brainstem volumes, cervical (C4/C7) cross-sectional area, and spirometry-measured lung volumes. CONCLUSIONS: Our study shows that brainstem volumes and spinal cord area are promising measures to predict respiratory intervention needs in ALS.

No evidence of cardiomyopathy in spinal and bulbar muscular atrophy.

OBJECTIVES: Spinal and bulbar muscular atrophy (SBMA) is a lower motor neuron disease caused by a CAG repeat expansion within the androgen receptor (AR) gene. Toxic nuclear accumulation of mutant AR has been observed in tissues other than nervous system including cardiac muscle. Moreover, CAG polymorphism length within AR has been associated with an increased risk of heart disease. MATERIALS AND METHODS: To test the hypothesis of the presence of cardiomyopathy in SBMA, a full cardiac protocol was applied to 25 SBMA patients. RESULTS: Patients' age ranged between 32 and 75 years. Cardiologic examination, 12-lead ECG, and echocardiography showed no abnormalities other than those consistent with hypertensive heart disease. One patient showed frequent supraventricular premature beats in absence of other significant arrhythmias at the 24-h ECG Holter. CONCLUSIONS: Our findings do not support the hypothesis of a primary cardiomyopathy in SBMA.

Comparison of spinal magnetic resonance imaging and classical clinical factors in predicting motor capacity in amyotrophic lateral sclerosis.

BACKGROUND: Motor capacity is crucial in amyotrophic lateral sclerosis (ALS) clinical trial design and patient care. However, few studies have explored the potential of multimodal MRI to predict motor capacity in ALS. This study aims to evaluate the predictive value of cervical spinal cord MRI parameters for motor capacity in ALS compared to clinical prognostic factors. METHODS: Spinal multimodal MRI was performed shortly after diagnosis in 41 ALS patients and 12 healthy participants as part of a prospective multicenter cohort study, the PULSE study (NCT00002013-A00969-36). Motor capacity was assessed using ALSFRS-R scores. Multiple stepwise linear regression models were constructed to predict motor capacity at 3 and 6 months from diagnosis, based on clinical variables, structural MRI measurements, including spinal cord cross-sectional area (CSA), anterior-posterior, and left-to-right cross-section diameters at vertebral levels from C1 to T4, and diffusion parameters in the lateral corticospinal tracts (LCSTs) and dorsal columns. RESULTS: Structural MRI measurements were significantly correlated with the ALSFRS-R score and its sub-scores. And as early as 3 months from diagnosis, structural MRI measurements fit the best multiple linear regression model to predict the total ALSFRS-R (R2 = 0.70, p value = 0.0001) and arm sub-score (R2 = 0.69, p value = 0.0002), and combined with DTI metric in the LCST and clinical factors fit the best multiple linear regression model to predict leg sub-score (R2 = 0.73, p value = 0.0002). CONCLUSIONS: Spinal multimodal MRI could be promising as a tool to enhance prognostic accuracy and serve as a motor function proxy in ALS.

CAG repeat length in androgen receptor gene is not associated with amyotrophic lateral sclerosis.

BACKGROUND: Epidemiological and clinical studies show higher prevalence of amyotrophic lateral sclerosis (ALS) in males than in females and more severe lesions in androgen receptor (AR)-expressing tissues. The AR gene contains a polymorphic CAG trinucleotide repeat, whose expansion over a certain threshold is toxic to motor neurons, causing spinal and bulbar muscular atrophy (SBMA). PURPOSE AND METHODS: We tested the hypothesis that the AR CAG repeat linked to SBMA is a risk factor for ALS. We analyzed AR CAG expansions in 336 patients with ALS and 100 controls. RESULTS: We found a negative association of AR CAG expansions with ALS susceptibility, clinical presentation, and survival. CONCLUSIONS: Our findings do not support a role of the AR CAG repeat length in ALS.

Genetic variation in KIFAP3 is associated with an upper motor neuron-predominant phenotype in amyotrophic lateral sclerosis.

BACKGROUND: Some authors have recently reported that the CC genotype of single-nucleotide polymorphism (SNP) rs1541160 mapping within the kinesin-associated protein 3 (KIFAP3) gene is associated with increased survival in sporadic amyotrophic lateral sclerosis (sALS). OBJECTIVE AND METHODS: The relationship between the rs1541160 genotype and several clinical features of 228 ALS patients was evaluated with the intent of assessing any association between the ALS phenotype and KIFAP3. The SNP rs1541160 within the KIFAP3 expression profile was investigated using real-time PCR in a group of 6 patients harboring the CC genotype and in 12 patients harboring the TT genotype. RESULTS: Analysis of our patients' clinical features showed that almost half of those with the CC genotype were classified as having upper motor neuron-predominant ALS (UMN-ALS). Conversely, there was an approximately 10% frequency of UMN-ALS in both the TT and the TC patient groups as well as in the entire cohort considered as a whole (p < 0.005). The SNP rs1541160 genotype did not appear to have any effect on patient survival or on KIFAP3 expression. CONCLUSIONS: The incidence of the UMN-ALS phenotype in the CC patients of this cohort supports the hypothesis that the SNP rs1541160 within the KIFAP3 gene is a potential modifier of the ALS phenotype.

Unimpaired Neuropsychological Performance and Enhanced Memory Recall in Patients with Sbma: A Large Sample Comparative Study.

Peculiar cognitive profile of patients with SBMA has been described by fragmented literature. Our retrospective study reports the neuropsychological evaluations of a large cohort of patients in order to contribute towards the understanding of this field. We consider 64 neuropsychological evaluations assessing mnesic, linguistic and executive functions collected from 2013 to 2015 in patients attending at Motor Neuron Disease Centre of University of Padova. The battery consisted in: Digit Span forwards and backwards, Prose Memory test, Phonemic Verbal fluency and Trail making tests. ANCOVA statistics were employed to compare tests scores results with those obtained from a sample of healthy control subjects. Multiple linear regressions were used to study the effect on cognitive performance of CAG-repeat expansion, the degree of androgen insensitivity and their interaction to cognitive performance. Statistical analyses did not reveal altered scores in any neuropsychological tests among those adopted. Interestingly, patients performed significantly better in the Prose Memory test's score. No relevant associations were found with genetic, hormonal or clinical patients' profile. Results inconsistent with previous studies have been interpreted according to the phenomenon of somatic mosaicism. We suggest a testosterone-related and the mood state-dependant perspectives as two possible interpretations of the enhanced performances in the Prose Memory test. Further studies employing more datailed tests batteries are encouraged.

Right hemisphere dysfunction and emotional processing in ALS: an fMRI study.

Emotional processing may be abnormal in amyotrophic lateral sclerosis (ALS). Our aim was to explore functional anatomical correlates in the processing of aversive information in ALS patients. We examined the performance of nine non-demented ALS patients and 10 healthy controls on two functional MRI (fMRI) tasks, consisting of an emotional attribution task and a memory recognition task of unpleasant versus neutral stimuli. During the emotional decision task, subjects were asked to select one of three unpleasant or neutral words. During the memory task, subjects were asked to recognize words presented during the previous task. Controls showed, as expected, greater activation in the right middle frontal gyrus during selection of unpleasant than neutral words, and a greater activation mainly in right-sided cerebral areas during the emotional recognition task. Conversely, patients showed a general increase in activation of the left hemisphere, and reduced activation in right hemisphere in both emotional tasks. Such findings may suggest extra-motor neurodegeneration involving key circuits of emotions, mostly negative, commonly involved in FTD.