Biological biomarkers in muscle diseases relevant for follow-up and evaluation of treatment.

Muscle diseases cover a diverse group of disorders that in most cases are hereditary. The rarity of the individual muscle diseases provides a challenge for researchers when wanting to establish natural history of the conditions and when trying to develop diagnostic tools, therapies, and outcome measures to evaluate disease progression. With emerging molecular therapies in many genetic muscle diseases, as well as biological therapies for the immune-mediated ones, biological biomarkers play an important role in both drug development and evaluation. In this review, we focus on the role of biological biomarkers in muscle diseases and discuss their utility as surrogate endpoints in therapeutic trials. We categorise these as either 1) disease unspecific markers, 2) markers of specific pathways that may be used for more than one disease or 3) disease-specific markers. We also propose that evaluation of specific therapeutic interventions benefits from biological markers that match the intervention.

Proteomics profiling and machine learning in nusinersen-treated patients with spinal muscular atrophy.

AIM: The availability of disease-modifying therapies and newborn screening programs for spinal muscular atrophy (SMA) has generated an urgent need for reliable prognostic biomarkers to classify patients according to disease severity. We aim to identify cerebrospinal fluid (CSF) prognostic protein biomarkers in CSF samples of SMA patients collected at baseline (T0), and to describe proteomic profile changes and biological pathways influenced by nusinersen before the sixth nusinersen infusion (T302). METHODS: In this multicenter retrospective longitudinal study, we employed an untargeted liquid chromatography mass spectrometry (LC-MS)-based proteomic approach on CSF samples collected from 61 SMA patients treated with nusinersen (SMA1 n=19, SMA2 n=19, SMA3 n=23) at T0 at T302. The Random Forest (RF) machine learning algorithm and pathway enrichment analysis were applied for analysis. RESULTS: The RF algorithm, applied to the protein expression profile of naïve patients, revealed several proteins that could classify the different types of SMA according to their differential abundance at T0. Analysis of changes in proteomic profiles identified a total of 147 differentially expressed proteins after nusinersen treatment in SMA1, 135 in SMA2, and 289 in SMA3. Overall, nusinersen-induced changes on proteomic profile were consistent with i) common effects observed in allSMA types (i.e. regulation of axonogenesis), and ii) disease severity-specific changes, namely regulation of glucose metabolism in SMA1, of coagulation processes in SMA2, and of complement cascade in SMA3. CONCLUSIONS: This untargeted LC-MS proteomic profiling in the CSF of SMA patients revealed differences in protein expression in naïve patients and showed nusinersen-related modulation in several biological processes after 10 months of treatment. Further confirmatory studies are needed to validate these results in larger number of patients and over abroader timeframe.

Clinical Phenotype of Pediatric and Adult Patients With Spinal Muscular Atrophy With Four SMN2 Copies: Are They Really All Stable?

OBJECTIVE: The aim of this study was to provide an overview of the clinical phenotypes associated with 4 SMN2 copies. METHODS: Clinical phenotypes were analyzed in all the patients with 4 SMN2 copies as part of a nationwide effort including all the Italian pediatric and adult reference centers for spinal muscular atrophy (SMA). RESULTS: The cohort includes 169 patients (102 men and 67 women) with confirmed 4 SMN2 copies (mean age at last follow-up = 36.9 ± 19 years). Six of the 169 patients were presymptomatic, 8 were classified as type II, 145 as type III (38 type IIIA and 107 type IIIB), and 8 as type IV. The remaining 2 patients were asymptomatic adults identified because of a familial case. The cross-sectional functional data showed a reduction of scores with increasing age. Over 35% of the type III and 25% of the type IV lost ambulation (mean age = 26.8 years ± 16.3 SD). The risk of loss of ambulation was significantly associated with SMA type (p < 0.0001), with patients with IIIB and IV less likely to lose ambulation compared to type IIIA. There was an overall gender effect with a smaller number of women and a lower risk for women to lose ambulation. This was significant in the adult (p = 0.009) but not in the pediatric cohort (p = 0.43). INTERPRETATION: Our results expand the existing literature on natural history of 4 SMN2 copies confirming the variability of phenotypes in untreated patients, ranging from type II to type IV and an overall reduction of functional scores with increasing age. ANN NEUROL 2023;94:1126-1135.

Long-term natural history in type II and III spinal muscular atrophy: a 4-year international study on the Hammersmith Functional Motor Scale Expanded.

BACKGROUND AND PURPOSE: Spinal muscular atrophy (SMA) is a genetic disorder caused by SMN1 gene mutations. Although studies on available disease-modifying treatments have reported their efficacy and safety, long-term natural history data are lacking for comparison. The aim of this prospective study was to report 4-year changes on the Hammersmith Functional Motor Scale Expanded (HFMSE) in type II and III SMA in relation to several variables such as age, functional status and SMN2 copy number. METHODS: The study involves retrospective analysis of prospectively collected data from international datasets (Belgium, Italy, Spain, USA, UK). HFMSE longitudinal changes were analyzed using linear mixed effect models, examining annualized HFMSE change and its association with variables such as age at baseline, sex, motor function, SMN2 copy number. RESULTS: In SMA type II (n = 226), the 4-year mean change was -2.20 points. The largest mean changes were observed in sitters aged 5-14 years and the lowest in those who lost the ability to sit unsupported. In SMA type III (n = 162), the 4-year mean change was -2.75 points. The largest mean changes were in those aged 7-15 years, whilst the lowest were in those below 7 and in the SMA type IIIa subgroup over 15. Age and score at baseline were predictive of 4-year changes. CONCLUSIONS: Our findings provide natural history reference data for comparison with long-term follow-up of clinical trials or real-world data, highlighting the need to define patterns of changes in smaller SMA subgroups instead of reporting mean changes across an entire SMA cohort.

Determining minimal clinically important differences in the Hammersmith Functional Motor Scale Expanded for untreated spinal muscular atrophy patients: An international study.

BACKGROUND AND PURPOSE: Spinal muscular atrophy (SMA) is a rare and progressive neuromuscular disorder with varying severity levels. The aim of the study was to calculate minimal clinically important difference (MCID), minimal detectable change (MDC), and values for the Hammersmith Functional Motor Scale Expanded (HFMSE) in an untreated international SMA cohort. METHODS: The study employed two distinct methods. MDC was calculated using distribution-based approaches to consider standard error of measurement and effect size change in a population of 321 patients (176 SMA II and 145 SMA III), allowing for stratification based on age and function. MCID was assessed using anchor-based methods (receiver operating characteristic [ROC] curve analysis and standard error) on 76 patients (52 SMA II and 24 SMA III) for whom the 12-month HFMSE could be anchored to a caregiver-reported clinical perception questionnaire. RESULTS: With both approaches, SMA type II and type III patients had different profiles. The MCID, using ROC analysis, identified optimal cutoff points of -2 for type II and -4 for type III patients, whereas using the standard error we found the optimal cutoff points to be 1.5 for improvement and -3.2 for deterioration. Furthermore, distribution-based methods uncovered varying values across age and functional status subgroups within each SMA type. CONCLUSIONS: These results emphasize that the interpretation of a single MCID or MDC value obtained in large cohorts with different functional status needs to be made with caution, especially when these may be used to assess possible responses to new therapies.

Parental diagnostic delay and developmental outcomes in congenital and childhood-onset myotonic dystrophy type 1.

AIM: To investigate the timing of type 1 myotonic dystrophy (DM1) diagnosis in parents of affected children and describe children's perinatal characteristics and developmental outcomes. METHOD: This was a descriptive case series of children with congenital myotonic dystrophy (CDM) and childhood-onset myotonic dystrophy (ChDM). Parental timing of DM1 diagnosis and the perinatal, motor, and cognitive outcomes of paediatric patients were recorded. RESULTS: A total of 139 children followed by 12 highly specialized tertiary care neuromuscular centres in Italy and one tertiary neuromuscular centre in the USA were included: 105 children with CDM and 34 children with ChDM (mean age 8 years 8 months and 12 years 2 months respectively; 49 males and 17 males respectively). Seventy (50%) parents were diagnosed with adult-onset DM1 after the affected child was diagnosed. Only 12 (17%) of the 69 parents known to be affected had prenatal testing. Of the 105 children with CDM, 98% had maternally inherited CDM, 36% were born preterm, 83% required a stay in the neonatal intensive care unit for more than 48 hours, 84% and 79% had ambulation and speech delay, and 84% had an IQ lower than 70. Of the 34 children with ChDM, 59% had paternally inherited ChDM, 91% were born at term, and 36% had an IQ lower than 70. INTERPRETATION: Delay in diagnosing DM1 affects family planning. The prenatal and perinatal outcomes of the affected offspring emphasize the need for proactive counselling as parents may be reluctant to conduct prenatal testing.

Prognostic factors for tube feeding in type I SMA patients treated with disease-modifying therapies: a cohort study.

The aim of this study was to assess the need for tube feeding in a cohort of treated infants with type I SMA and to identify predictive factors. All patients were classified at baseline, when treatment started, and at follow-up according to their functional level and the need for tube feeding. Fisher's exact test was used to examine the associations between the outcome at the last follow-up and SMA type, SMN2 copy number, and baseline nutritional status. ANOVA was performed to compare CHOP INTEND scores and age at treatment initiation with outcomes. The cohort includes 75 type I SMA infants treated between 0.1 and 5 years of age. At the last follow-up, 34 had no need for tube feeding, 9 had tube feeding but were also able to be fed by mouth, and 32 had tube feeding and were unable to be fed by mouth. Thirty of the 41 infants with tube feeding at follow-up already had feeding difficulties when treatment was started. The need for tube feeding at follow-up was associated with the level of feeding involvement at baseline and with CHOP INTEND scores [p < 0.001] but not with SMN2 copy number, SMA type 1 subtypes or age at treatment. The results of this study suggest that the need for tube feeding is not frequent in treated infants with type I SMA and, when occurring, can be predicted by the level of feeding involvement and low CHOP INTEND scores at baseline. What is Known: • The advent of disease-modifying therapies is increasingly changing the approach to swallowing and nutritional management in type I SMA. • Clinical trials and real-world data using all three disease-modifying therapies report a rather wide variability of feeding outcome and need for tube feeding that is often related to different cohorts that makes comparison between studies very difficult. What is New: • The real-world findings of this study, including all the children treated since treatments became available, confirmed that the need for tube feeding is not an invariable finding. • The level of feeding involvement at baseline appears to be a reliable prognostic indicator of bulbar outcome. • The results highlight the need for interventional studies with structured Speech and Language Therapist protocols that will help to better understand the extent to which bulbar function can be maintained or regained even in children requiring tube feeding.

Facial nerve vulnerability in spinal muscular atrophy and motor unit number index of the orbicularis oculi muscle.

INTRODUCTION/AIMS: Measures for assessing cranial nerve vulnerability in spinal muscular atrophy (SMA) have not yet been determined. Motor unit number index (MUNIX) studies have shown correlations with disease severity but have been used only in limb muscles. In the present study, we explore facial nerve response, MUNIX, and motor unit size index (MUSIX) of the orbicularis oculi muscle in a cohort of patients with SMA. METHODS: Facial nerve response (measured as compound muscle action potential, CMAP), MUNIX, and MUSIX of the orbicularis oculi muscle were cross-sectionally recorded in patients with SMA and compared to healthy control subjects (HCs). Active maximum mouth opening (aMMO) was also measured at baseline in our SMA cohort. RESULTS: Thirty-seven patients with SMA (21 SMA II; 16 SMA III) and 27 HCs were recruited. CMAP of the facial nerve and MUNIX of orbicularis oculi proved to be feasible and well tolerated techniques. CMAP amplitude and MUNIX scores were significantly lower in patients with SMA compared to HCs (p < .0001). Both MUNIX and CMAP amplitude were significantly higher in patients with SMA III compared to SMA II. No significant difference emerged comparing CMAP amplitude, MUNIX and MUSIX scores between those with different functional status or nusinersen treatment. DISCUSSION: Our results provide neurophysiological evidence of facial nerve and muscle involvement in patients with SMA. CMAP of the facial nerve and MUNIX of orbicularis oculi showed high accuracy in discriminating between the various subtypes of SMA and in quantifying the motor unit loss of the facial nerve.

The Facioscapulohumeral Muscular Dystrophy-Health Index: Development and evaluation of a disease-specific outcome measure.

INTRODUCTION/AIMS: As promising therapeutic interventions are tested among patients with facioscapulohumeral muscular dystrophy (FSHD), there is a clear need for valid and reliable outcome tools to track disease progression and therapeutic gain in clinical trials and for clinical monitoring. Our aim was to develop and validate the Facioscapulohumeral Muscular Dystrophy-Health Index (FSHD-HI) as a multifaceted patient-reported outcome measure (PRO) designed to measure disease burden in adults with FSHD. METHODS: Through initial interviews with 20 individuals and a national cross-sectional study with 328 individuals with FSHD, we identified the most prevalent and impactful symptoms in FSHD. The most relevant symptoms were included in the FSHD-HI. We used patient interviews, test-retest reliability evaluation, known groups validity testing, and factor analysis to evaluate and optimize the FSHD-HI. RESULTS: The FSHD-HI contains 14 subscales that measure FSHD disease burden from the patient's perspective. Fourteen adults with FSHD participated in semistructured beta interviews and found the FSHD-HI to be clear, usable, and relevant to them. Thirty-two adults with FSHD participated in test-retest reliability assessments, which demonstrated the high reliability of the FSHD-HI total score (intraclass correlation coefficient = 0.924). The final FSHD-HI and its subscales also demonstrated a high internal consistency (Cronbach α = 0.988). DISCUSSION: The FSHD-HI provides researchers and clinicians with a reliable and valid mechanism to measure multifaceted disease burden in patients with FSHD. The FSHD-HI may facilitate quantification of therapeutic effectiveness, as demonstrated by its use as a secondary and exploratory measure in several clinical trials.

Continued benefit of nusinersen initiated in the presymptomatic stage of spinal muscular atrophy: 5-year update of the NURTURE study.

INTRODUCTION/AIMS: NURTURE (NCT02386553) is an open-label study of nusinersen in children (two SMN2 copies, n = 15; three SMN2 copies, n = 10) who initiated treatment in the presymptomatic stage of spinal muscular atrophy (SMA). A prior analysis after ~3 y showed benefits on survival, respiratory outcomes, motor milestone achievement, and a favorable safety profile. An additional 2 y of follow-up (data cut: February 15, 2021) are reported. METHODS: The primary endpoint is time to death or respiratory intervention (≥6 h/day continuously for ≥7 days or tracheostomy). Secondary outcomes include overall survival, motor function, and safety. RESULTS: Median age of children was 4.9 (3.8-5.5) y at last visit. No children have discontinued the study or treatment. All were alive. No additional children utilized respiratory intervention (defined per primary endpoint) since the prior data cut. Children with three SMN2 copies achieved all World Health Organization (WHO) motor milestones, with all but one milestone in one child within normal developmental timeframes. All 15 children with two SMN2 copies achieved sitting without support, 14/15 walking with assistance, and 13/15 walking alone. Mean Hammersmith Functional Motor Scale Expanded total scores showed continued improvement. Subgroups with two SMN2 copies, minimum baseline compound muscle action potential amplitude ≥2 mV, and no baseline areflexia had better motor and nonmotor outcomes versus all children with two SMN2 copies. DISCUSSION: These results demonstrate the value of early treatment, durability of treatment effect, and favorable safety profile after ~5 y of nusinersen treatment. Inclusion/exclusion criteria and baseline characteristics should be considered when interpreting presymptomatic SMA trial data.

Type I spinal muscular atrophy patients treated with nusinersen: 4-year follow-up of motor, respiratory and bulbar function.

BACKGROUND: We report the 4-year follow-up in type I patients treated with nusinersen and the changes in motor, respiratory and bulbar function in relation to subtype, age and SMN2 copy number. METHODS: The study included SMA 1 patients with at least one assessment after 12, 24 and 48 months from the first dose of nusinersen. The assessments used were Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND) and the Hammersmith Infant Neurological Examination (HINE-II). RESULTS: Forty-eight patients, with ages ranging from 7 days to 12 years (mean 3.3 years, SD 3.6 years) were included in the study. The CHOP INTEND and HINE-II scores significantly increased between baseline and 48 months (p < 0.001). When age at starting treatment subgroups (<210 days, <2 years, 2-4 years, 5-11 years, ≥12 years) were considered, the CHOP INTEND increased significantly in patients younger than 4 years at treatment, while the HINE-2 increased significantly in patients younger than 2 years at treatment. In a mixed-model analysis, age, nutritional and respiratory status were predictive of changes on both scales while SMN2 copy number and decimal classification were not. CONCLUSIONS: Our results confirm the safety profile previously reported and support the durability of the efficacy of nusinersen at 4 years with an overall stability or mild improvement and no evidence of deterioration over a long period of time.

Development of prediction models based on respiratory assessments to determine the need for non-invasive ventilation in patients with myotonic dystrophy type 1.

INTRODUCTION: Myotonic dystrophy type 1 is a slowly progressive, multisystem, autosomal dominant disorder, in which the impairments of respiratory systems represent one of the main causes of death. OBJECTIVE: The aim of our study is to develop prediction models to identify the most appropriate test(s) providing indication for NIV. METHODS: DM1 patients attending the NEMO Clinical Center (Milan) between January 2008 and July 2020, who had been subjected to a complete battery of respiratory tests, were retrospectively recruited. Demographic, clinical, and anthropometric characteristics were collected, as well as arterial blood gas (ABG) analysis, spirometry, respiratory muscle strength, cough efficacy, and nocturnal oximetry as respiratory assessments. Patients were stratified in those requiring NIV and those with normal respiratory function. RESULTS: Out of 151 DM1 patients (median age: 44 years [35.00-53.00]; male/female ratio: 0.80 (67/84)), 76 had an indication for NIV initiation (50.33%). ABG, spirometry, and nocturnal oximetry prediction models resulted in an excellent discriminatory ability in distinguishing patients who needed NIV from those who did not (AUC of 0.818, 0.808, and 0.935, respectively). An easy-to-use calculator was developed to automatically determine a score of NIV necessity based on the prediction equations generated from each aforementioned prediction model. CONCLUSIONS: The proposed prediction models may help to identify which patients are at a higher risk of requiring ventilator support and therefore help in defining individual management plans and criteria for specific interventions early in the disease course.

Patient-reported outcome measures in drugs for neurological conditions approved by European Medicines Agency 2017-2022.

BACKGROUND: Regulatory agencies have been responsive to public demand for inclusion of the patient experience in evaluating and approving therapies. Over the years, patient-reported outcome measures (PROMs) have become increasingly prevalent in clinical trial protocols; however, their influence on regulators, payers, clinicians, and patients' decision-making is not always clear. We recently conducted a cross-sectional study aimed at investigating the use of PROMs in new regulatory approvals of drugs for neurological conditions between 2017 and 2022 in Europe. METHODS: We reviewed European Public Assessment Reports (EPARs) and recorded on a predefined data extraction form whether they considered PROMs, their characteristics (e.g., primary/secondary endpoint, generic/specific instrument) and other relevant information (e.g., therapeutic area, generic/biosimilar, orphan status). Results were tabulated and summarized by means of descriptive statistics. RESULTS: Of the 500 EPARs related to authorized medicines between January 2017 and December 2022, 42 (8%) concerned neurological indications. Among the EPARs of these products, 24 (57%) reported any use of PROMs, typically considered as secondary (38%) endpoints. In total, 100 PROMs were identified, of which the most common were the EQ-5D (9%), the SF-36 (6%), or its shorter adaptation SF-12, the PedsQL (4%). CONCLUSIONS: Compared to other disease areas, neurology is one where the use of patient-reported outcomes evidence is inherently part of the clinical evaluation and for which core outcome sets exist. Better harmonization of the instruments recommended for use would facilitate the consideration of PROMs at all stages in the drug development process.

Clinimetrics of the cognitive section of the Italian ALS Cognitive Behavioral Screen (ALS-CBS™).

BACKGROUND: The present study aimed at (1) providing further validity and reliability evidence for the Italian version of the cognitive section of the ALS Cognitive Behavioral Screen (ALS-CBS™) and (2) testing its diagnostics within an Italian ALS cohort, as well as at (3) exploring its capability to discriminate patients from healthy controls (HCs). METHODS: N = 293 non-demented ALS patients were administered the cognitive sections of the ALS-CBS™ and Edinburgh Cognitive and Behavioural ALS Screen (ECAS). N = 96 HCs demographically matched with N = 96 patients were also administered the cognitive section of the ALS-CBS™. In patients, factorial and construct validity, internal reliability, and diagnostics against a defective score on the cognitive section of the ECAS were tested. Case-control discrimination was assessed via a logistic regression. RESULTS: ALS-CBS™ cognitive subscales were underpinned by a simple, unidimensional structure, internally reliable (McDonald's ω = 0.74), and mostly related with ECAS executive and fluency scores (rs = 0.54-0.71). Both raw and age- and education-adjusted scores on the cognitive section of the ALS-CBS™ accurately detected ECAS-defined cognitive impairment (AUC = 0.80 and .88, respectively), yielding optimal error-based, information-based and unitary diagnostics. A cut-off of < 15.374 was identified on adjusted scores. The test was able to discriminate patients from HCs (p < 0.001). DISCUSSION: The cognitive section of the Italian ALS-CBS™ is a valid, reliable, and diagnostically sound ALS-specific screener for detecting frontotemporal, executive-/attentive-based cognitive inefficiency in non-demented ALS patients, being also able to discriminate them from normotypical individuals.

Peri-partum respiratory management of pregnant women with neuro-muscular disorders: a prospective observational study (IT-NEUMA-Pregn study).

BACKGROUND: Pregnant women with neuromuscular diseases (NMDs) often display respiratory muscle impairment which increases the risk for pulmonary complications (PCs). The aim of this study was to identify pregnant NMDs patients with pulmonary risk factors and to apply in these women non-invasive ventilation (NIV) combined with mechanical insufflation-exsufflation (MI-E) in the peri-partum period. METHODS: We conducted a multicenter observational study on women with NMDs undergoing cesarean section or spontaneous labor in a network of 7 national hospitals. In these subjects we applied a protocol for screening and preventing PCs, and we evaluated PCs rate, maternal and neonatal outcome. RESULTS: Twenty-four patients out of the 94 enrolled pregnant women were at risk for PCs and were trained or retrained to use NIV and/or MI-E before delivery. After delivery, 17 patients required NIV with or without MI-E. Despite nine out of the 24 women at pulmonary risk developed postpartum PCs, none of them needed reintubation nor tracheostomy. In addition, the average birth weight and Apgar score were normal. Only one patient without pulmonary risk factors developed postpartum PCs. CONCLUSION: This study showed the feasibility of applying a protocol for screening and treating pregnant NMDs women with pulmonary risk. Despite a PCs rate of 37% was observed in these patients, maternal and neonatal outcome were favorable.

Assessing Prevalence and Characteristics of Oro-bulbar Involvement in Children and Adults with SMA Type 2 and 3 Using a Multimodal Approach.

Bulbar and jaw muscles are impaired in patients with Spinal Muscular Atrophy (SMA) but the assessment of their severity and progression are limited by the lack of age-appropriate and disease-specific measures. We investigated mastication and swallowing in children and adults with SMA, sitters and walkers. In a 2-year multicentre cross-sectional prospective study, lip and tongue strength (Iowa Oral Performance Instrument), chewing and swallowing (Test of Masticating and Swallowing Solids), active mouth opening (aMMO) were compared to age-appropriate normative data. The perceived burden of oro-bulbar involvement (SMA-Health Index) was recorded. 78 patients were included, 45 children (median age 7.4 years),22 adults (median age 26.8 years) on nusinersen and 11 untreated (median age 32.7 years). Forty-three percent children had reduced mouth opening, 50% had prolonged total time to eat. These issues were more prominent in sitters than in walkers (p = 0.019, p = 0.014). Sixty-six percent needed increased swallows for bolus clearance. Nusinersen treated adults had median aMMO, tongue strength and total time at TOMASS values within normal range (z score: -1.40, -1.22, -1.32, respectively) whereas untreated adults had reduced aMMO (z score: -2.68) and tongue strength (z score: -2.20). Only a minority of children (2/17) and treated adults (5/21) reported burden in swallowing or mastication compared to all untreated adults (5/5). After 16 months, mastication and swallowing were stable in treated children and adults, whether sitters or walkers. The reported multimodal approach to assess oro-bulbar functions demonstrate that swallowing and mastication are impaired in SMA despite patients' perception. These results suggest a trend towards stabilization of oro-bulbar function in patients on long-term treatment with nusinersen.

The hypometabolic state: a good predictor of a better prognosis in amyotrophic lateral sclerosis.

BACKGROUND: Malnutrition and weight loss are negative prognostic factors for survival in patients with amyotrophic lateral sclerosis (ALS). However, energy expenditure at rest (REE) is still not included in clinical practice, and no data are available concerning hypometabolic state in ALS. OBJECTIVE: To evaluate in a referral cohort of patients with ALS the prevalence of hypometabolic state as compared with normometabolic and hypermetabolic states, and to correlate it with clinical phenotype, rate of progression and survival. DESIGN: We conducted a retrospective study examining REE measured by indirect calorimetry in patients with ALS referred to Milan, Limoges and Tours referral centres between January 2011 and December 2017. Hypometabolism and hypermetabolism states were defined when REE difference between measured and predictive values was ≤-10% and ≥10%, respectively. We evaluated the relationship between these metabolic alterations and measures of body composition, clinical characteristics and survival. RESULTS: Eight hundred forty-seven patients with ALS were recruited. The median age at onset was 63.79 years (IQR 55.00-71.17). The male/female ratio was 1.26 (M/F: 472/375). Ten per cent of patients with ALS were hypometabolic whereas 40% were hypermetabolic. Hypometabolism was significantly associated with later need for gastrostomy, non-invasive ventilation and tracheostomy placement. Furthermore, hypometabolic patients with ALS significantly outlived normometabolic (HR=1.901 (95% CI 1.080 to 3.345), p=0.0259) and hypermetabolic (HR=2.138 (95% CI 1.154 to 3.958), p=0.0157) patients. CONCLUSION: Hypometabolism in ALS is not uncommon and is associated with slower disease progression and better survival than normometabolic and hypermetabolic subjects. Indirect calorimetry should be performed at least at time of diagnosis because alterations in metabolism are correlated with prognosis.

Body composition and myokines in a cohort of patients with Becker muscular dystrophy.

INTRODUCTION/AIMS: Becker muscular dystrophy (BMD) is an X-linked disease leading to muscle wasting and weakness. The decrease in lean body mass (LBM) in Duchenne muscular dystrophy, has shown correlation with loss of muscle function and bone density (BD). Myokines (including irisin) are hormones secreted by skeletal muscle that allow crosstalk between muscle and bone. The present study analyzed body composition and circulating myokine levels in a cohort of BMD patients; moreover, the association between dual energy X-ray absorptiometry (DXA) parameters, functional motor assessments, and myokine levels was investigated. METHODS: All patients underwent DXA, blood samples for myokine assays, and functional motor assessments. A group of healthy controls (HCs) was also included. RESULTS: Thirty BMD patients, median age at evaluation 36.0 y [26.0-41.0], were included. Twenty-nine patients underwent whole-body DXA. Median value of total body Z-score was -0.70. The prevalence of low skeletal muscle mass defined as appendicular skeletal muscle mass index (ASMMI) < 7.59 kg/m2 was 83%. Irisin levels were significantly lower in BMD compared to HCs (p = .03). All DXA parameters showed significant correlation with the functional motor assessments, in particular the h2 -standardized lean mass lower limb index (p = .0006); h2 -standardized total fat mass showed negative correlations with North Star Ambulatory Assessment and 6 min walk test (p = .03). DISCUSSION: DXA is a useful tool to evaluate body composition in BMD patients; the decrease in BD and LBM is associated with a reduction of motor function in BMD.

Body mass index in type 2 spinal muscular atrophy: a longitudinal study.

The aim of this retrospective study was to review body mass index (BMI) in a large cohort of Italian pediatric type 2 spinal muscular atrophy (SMA) patients, aged between 0 and 20 years and to establish possible differences in relation to a number of variables such as ventilation, motor function, and survival motor neuron 2 gene copies. Cross-sectional data were collected from 102 patients for a total of 344 visits. Standard growth charts for height and weight were used as reference, with age adjusted BMI calculated using the Center for Disease and Prevention Children's BMI Tool. In the 344 visits, weight ranged between 3.90 and 83 kg, and the BMI between 8.4 and 31.6 with a BMI/age z-scores < - 2SD present in 28% and BMI/age z-scores > + 2SD in 9% of the measurements. The BMI/age z-scores were relatively stable < 5 years of age with an increasing number of patients < - 2SD after the age of 5, and a wider range of BMI/age z-scores after the age of 13. A difference on the BMI/age z-scores was found among the different age subgroups (< 5, 5-12, ≥ 13 years). A multivariate analysis in 58 patients with longitudinal assessments showed that baseline BMI/age z-scores and gender were significantly contributing to the changes while other variables were not. CONCLUSION: Our results confirm that careful surveillance of weight and BMI/age z-scores is needed in type 2 SMA. Further studies, including assessments of chewing and swallowing and of lean/fat body mass, will help to better understand the possible mechanisms underlying weight issues. WHAT IS KNOWN: • Feeding difficulties have been reported in a few studies and were invariably found in patients with type 1 SMA. • Type 2 SMA patients often have low BMI with a relevant number of patients requiring tube feeding. WHAT IS NEW: • Reduction in BMI/age z-score overtime appeared to depend on baseline BMI/age z-score and gender. • Patients with a low BMI/age z-score were at higher risk of developing further reduction.

Cross-Cultural Adaptation and Validation of the Italian Version of the Dysphagia Handicap Index (I-DHI).

The Dysphagia Handicap Index (DHI) is a valid Health-related Quality of Life (HRQOL) questionnaire for patients with oropharyngeal dysphagia (OD) of heterogeneous etiologies. The study aimed at crossculturally translating and adapting the DHI into Italian (I-DHI) and analyzing I-DHI reliability, validity, and interpretability. The I-DHI was developed according to Beaton et al. 5-stage process and completed by 75 adult OD patients and 166 healthy adults. Twenty-six patients filled out the I-DHI twice, 2 weeks apart, for test-retest reliability purposes. Sixty-two patients completed the Italian-Swallowing Quality of Life Questionnaire (I-SWAL-QoL) for criterion validity analysis. Construct validity was tested comparing I-DHI scores among patients with different instrumentally assessed and self-rated OD severity, comparing patients and healthy participants and testing Spearman's correlations among I-DHI subscales. I-DHI interpretability was assessed and normative data were generated. Participants autonomously completed the I-DHI in maximum 10 min. Reliability proved satisfactory for all I-DHI subscales (internal consistency: α > .76; test-retest reliability: intraclass correlation coefficient > .96, k = .81). Mild to moderate correlations (- .26 ≤ ρ ≤ - .72) were found between I-DHI and I-SWAL-QoL subscales. Construct validity proved satisfactory as (i) moderate to strong correlations (.51 ≤ ρ ≤ .90) were found among I-DHI subscales; (ii) patients with more severe instrumentally or self-assessed OD reported higher I-DHI scores (p < .05); and (iii) OD patients scored higher at I-DHI compared to healthy participants (p < .05). Interpretability analyses revealed a floor effect for the Emotional subscale only and higher I-DHI scores (p < .05) for healthy participants > 65 years. In conclusion, the I-DHI is a reliable and valid HRQOL tool for Italian adults with OD.