Optimizing telemedicine to facilitate amyotrophic lateral sclerosis clinical trials

Longitudinal comparison of the self-administered ALSFRS-RSE and ALSFRS-R as functional outcome measures in ALS

Objective: Test the feasibility, adherence rates and optimal frequency of digital, remote assessments using the ALSFRS-RSE via a customized smartphone-based app. Methods: This fully remote, longitudinal study was conducted over a 24-week period, with virtual visits every 3 months and weekly digital assessments. 19 ALS participants completed digital assessments via smartphone, including a digital version of the ALSFRS-RSE and mood survey. Interclass correlation coefficients (ICC) and Bland-Altman plots were used to assess agreement between staff-administered and self-reported ALSFRS-R pairs. Longitudinal change was evaluated using ANCOVA models and linear mixed models, including impact of mood and time of day. Impact of frequency of administration of the ALSFRS-RSE on precision of the estimate slope was tested using a mixed effects model. Results: In our ALS cohort, digital assessments were well-accepted and adherence was robust, with completion rates of 86%. There was excellent agreement between the digital self-entry and staff-administered scores computing multiple ICCs (ICC range = 0.925-0.961), with scores on the ALSFRS-RSE slightly higher (1.304 points). Digital assessments were associated with increased precision of the slope, resulting in higher standardized response mean estimates for higher frequencies, though benefit appeared to diminish at biweekly and weekly frequency. Effects of participant mood and time of day on total ALSFRS-RSE score were evaluated but were minimal and not statistically significant. Conclusion: Remote collection of digital patient-reported outcomes of functional status such as the ALSFRS-RSE yield more accurate estimates of change over time and provide a broader understanding of the lived experience of people with ALS.

Narrative review of telemedicine applications in decentralized research

Telemedicine enables critical human communication and interaction between researchers and participants in decentralized research studies. There is a need to better understand the overall scope of telemedicine applications in clinical research as the basis for further research. This narrative, nonsystematic review of the literature sought to review and discuss applications of telemedicine, in the form of synchronous videoconferencing, in clinical research. We searched PubMed to identify relevant literature published between January 1, 2013, and June 30, 2023. Two independent screeners assessed titles and abstracts for inclusion, followed by single-reviewer full-text screening, and we organized the literature into core themes through consensus discussion. We screened 1044 publications for inclusion. Forty-eight publications met our inclusion and exclusion criteria. We identified six core themes to serve as the structure for the narrative review: infrastructure and training, recruitment, informed consent, assessment, monitoring, and engagement. Telemedicine applications span all stages of clinical research from initial planning and recruitment to informed consent and data collection. While the evidence base for using telemedicine in clinical research is not well-developed, existing evidence suggests that telemedicine is a potentially powerful tool in clinical research.

Facioscapulohumeral Muscular Dystrophy European Patient Survey: Assessing Patient Reported Disease Burden and Preferences in Clinical Trial Participation

Background

Facioscapulohumeral muscular dystrophy (FSHD) is a genetic disorder characterized by progressive muscle weakness leading to permanent disability. There are no curative treatments, however, there are several upcoming clinical trials testing new therapies in FSHD.

Objective

This study aimed to explore the disease burden and patient preferences of people with FSHD to ensure that clinical trials can be designed to include outcome measures that are relevant and important to patients.

Methods

A survey was developed with a steering committee clinicians and physiotherapists with relevant experience in the disease, patient representatives, a registry expert and industry consultants. Themes of the survey included; participant demographics, disease progression and impact on function, factors encouraging or discouraging clinical trial participation, and positive outcomes of a clinical trial.

Results

1147 participants responded to the online survey, representing 26 countries across Europe and a range of disease severities. The study highlighted the key symptoms causing concern for FSHD patients - muscle weakness and mobility issues - reflecting what participants want targeted for future therapies. The need for clear information and communication throughout clinical trials was emphasised. Factors most encouraging trial participation included access to new investigational therapies, access to trial results and benefits for the FSHD community. Factors most discouraging trial participation included travel related issues and fear of side effects.

Conclusions

The results from this study identify the patient reported burden of FSHD and should provide researchers and industry with areas of therapeutic research that would be meaningful to patients, as well as supporting the development of patient centric outcome measures in clinical trials.

Maximum Phonation Time as a Surrogate Marker for Airway Clearance Physiologic Capacity and Pulmonary Function in Individuals With Amyotrophic Lateral Sclerosis

PURPOSE

The increased use of telehealth practices has created a critical need for home-based surrogate markers for prognostic respiratory indicators of disease progression in persons with amyotrophic lateral sclerosis (pALS). Given that phonation relies on the respiratory subsystem of speech production, we aimed to examine the relationships between maximum phonation time (MPT), forced vital capacity, and peak cough flow and to determine the discriminant ability of MPT to detect forced vital capacity and peak cough flow impairments in pALS.

METHOD

MPT, peak cough flow, forced vital capacity, and ALS Functional Rating Scale scores were obtained from 62 pALS (El-Escorial Revised) every 3 months as part of a longitudinal natural history study. Pearson's correlations, linear regressions, and receiver operator characteristic curve analyses with the area under the curve (AUC), sensitivity, specificity, and likelihood ratios were calculated.

RESULTS

The mean age of pALS was 63.14 ± 10.95 years, 49% were female, and 43% had bulbar onset. MPT predicted forced vital capacity, F(1, 225) = 117.96, p < .0001, and peak cough flow, F(1, 217) = 98.79, p < .0001. A significant interaction was noted between MPT and ALS Functional Rating Scale-Revised respiratory subscore for forced vital capacity, F(1, 222) = 6.7, p = .010, and peak cough flow, F(1, 215) = 4.37, p = .034. The discriminant ability of MPT was excellent for peak cough flow (AUC = 0.88) and acceptable for forced vital capacity (AUC = 0.78).

CONCLUSIONS

MPT is a simple clinical test that can be measured via telehealth and represents a potential surrogate marker for important respiratory and airway clearance indices. Further larger studies are required to validate these findings with remote data collection.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.22186408.

Wearable device and smartphone data quantify ALS progression and may provide novel outcome measures

Amyotrophic lateral sclerosis (ALS) therapeutic development has largely relied on staff-administered functional rating scales to determine treatment efficacy. We sought to determine if mobile applications (apps) and wearable devices can be used to quantify ALS disease progression through active (surveys) and passive (sensors) data collection. Forty ambulatory adults with ALS were followed for 6-months. The Beiwe app was used to administer the self-entry ALS functional rating scale-revised (ALSFRS-RSE) and the Rasch Overall ALS Disability Scale (ROADS) surveys every 2-4 weeks. Each participant used a wrist-worn activity monitor (ActiGraph Insight Watch) or an ankle-worn activity monitor (Modus StepWatch) continuously. Wearable device wear and app survey compliance were adequate. ALSFRS-R highly correlated with ALSFRS-RSE. Several wearable data daily physical activity measures demonstrated statistically significant change over time and associations with ALSFRS-RSE and ROADS. Active and passive digital data collection hold promise for novel ALS trial outcome measure development.

Amyotrophic lateral sclerosis: a neurodegenerative disorder poised for successful therapeutic translation

Amyotrophic lateral sclerosis (ALS) is a devastating disease caused by degeneration of motor neurons. As with all major neurodegenerative disorders, development of disease-modifying therapies has proven challenging for multiple reasons. Nevertheless, ALS is one of the few neurodegenerative diseases for which disease-modifying therapies are approved. Significant discoveries and advances have been made in ALS preclinical models, genetics, pathology, biomarkers, imaging and clinical readouts over the last 10-15 years. At the same time, novel therapeutic paradigms are being applied in areas of high unmet medical need, including neurodegenerative disorders. These developments have evolved our knowledge base, allowing identification of targeted candidate therapies for ALS with diverse mechanisms of action. In this Review, we discuss how this advanced knowledge, aligned with new approaches, can enable effective translation of therapeutic agents from preclinical studies through to clinical benefit for patients with ALS. We anticipate that this approach in ALS will also positively impact the field of drug discovery for neurodegenerative disorders more broadly.

Primary lateral sclerosis natural history study - planning, designing, and early enrollment

Introduction/Aims. Primary lateral sclerosis (PLS) is exceedingly rare and has been an enigmatic disease. Recent progress has drastically changed this perception, with early biomarkers being investigated and potential medications for PLS emerging at the preclinical stage. The aim of this paper is to describe a study of PLS natural history and discuss the limitations and proposed solutions to the study of a rare and slowly progressive disease. Methods. The PLS Natural History Study is a 30-site, 24-month, prospective study that is supported by multiple funding sources. The study aims to enroll 50 early PLS (disease duration ≤4 years) and 50 definite PLS (disease duration 4 to 15 years) participants using modified PLS Diagnostic Criteria. Smartphone-based assessments including semi-quantitative and quantitative measures and patient-reported outcomes are utilized. In-person quantitative measures are also completed during site visits. The change in the PLS Functional Rating Scale score is the primary outcome. The study utilizes the NeuroBANK^® patient-centric data capture and management platform. The biostatistical analysis plan has been developed. Results. In one year, 28 participants have been recruited. Enrollment has been much slower than anticipated due to the COVID-19 pandemic, the rarity of PLS, and potential study competition for internal resources from ALS clinical trials. Discussion. We discuss the need for more innovative methods to enroll and study individuals with such rare diseases and propose a number of mechanisms by which more efficient enrollment could be facilitated.

The future of ALS diagnosis and staging: where do we go from here?

Amyotrophic lateral sclerosis (ALS) is a rare, progressive multi-system neurodegenerative disorder. Its clinical presentation varies considerably leading to delays in diagnosis, which has dire consequences in a disease where early intervention is key to optimize outcomes and limit care giver burden. There are a range of diagnostic criteria available to aid ALS diagnosis, as well staging methods to assess disease progression. However, they all suffer from inter-rater variability, complexity, and confusion in use. Such difficulties, when medical appointment times are limited and becoming more virtually based, have the potential to amplify uncertainty and errors in ALS diagnosis and prognosis. This review provides a clinical overview of the best way to balance the needs of evidence-based medicine and the patient. We focus on ALS diagnostic criteria and staging systems currently in use in clinical practice and explore factors that could enhance diagnostic efficiency and assessment of disease progression.

Longitudinal comparison of the self-entry Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-RSE) and Rasch-Built Overall Amyotrophic Lateral Sclerosis Disability Scale (ROADS) as outcome measures in people with amyotrophic lateral sclerosis

INTRODUCTION/AIMS

Improved functional outcome measures in amyotrophic lateral sclerosis (ALS) would aid ALS trial design and help hasten drug discovery. We evaluate the longitudinal performance of the Rasch-Built Overall Amyotrophic Lateral Sclerosis Disability Scale (ROADS) compared to the Amyotrophic Lateral Sclerosis Functional Rating Scale Revised for Self-Entry (ALSFRS-RSE) as patient reported outcomes of functional status in people with ALS.

METHODS

Participants completed the ROADS and the ALSFRS-RSE questionnaires at baseline, 3-, 6-, and 12- mo using Research Electronic Data Capture as part of a prospective, longitudinal, remote, online survey study of fatigue in ALS from 9/2020 to 12/2021. The scales were compared cross-sectionally (at baseline) and longitudinally. Correlation coefficients, coefficients of variation, and descriptive statistics were assessed.

RESULTS

A total of 182 adults with ALS consented to the study. This volunteer sample was comprised of predominantly White, non-Hispanic, non-smoking participants. Consented participant survey completion was approximately 90% at baseline and greater than 40% at 12 mo. The ALSFRS-RSE and the ROADS had high, significant agreement at 3 and 6 mo by Cohen's kappa ≥71% (p < 0.001); the number of functional increases or plateaus on the two scales were not significantly different; and the coefficient of variation of functional decline was similar at the 6-month mark, though higher for the ROADS at 3 mo and lower at 12 mo.

DISCUSSION

Although the ROADS performed similarly to the ALSFRS-RSE in an observational cohort, it has psychometric advantages, such as Rasch-modeling and unidimensionality. It merits further investigation as a patient reported outcome of overall disability and efficacy outcome measure in ALS trials.

Covid-19 threat and coping: application of protection motivation theory to the pandemic experiences of people affected by amyotrophic lateral sclerosis

BACKGROUND

People with amyotrophic lateral sclerosis (ALS) are at high risk for severe outcomes from Covid-19 infection. Researchers exploring ALS and Covid-19 have focused primarily on system response and adaptation. Using Protection Motivation Theory, we investigated how people with ALS and family caregivers appraised and responded to Covid-19 threat, the 'costs' associated with pandemic response, and how health professionals and systems can better support people affected by ALS who are facing public health emergencies.

METHODS

Data were drawn from the 'ALS Talk Project,' an asynchronous, moderated focus group study. Participants were recruited from regions across Canada. Seven groups met online over 14 weeks between January and July 2020. Fifty-three participants contributed to Covid-19 discussions. Data were qualitatively analyzed using directed content analysis and the constant-comparative approach.

RESULTS

Participants learned about the Covid-19 pandemic from the media. They rapidly assessed their vulnerability and responded to Covid-19 threat by following recommendations from health authorities, information monitoring, and preparing for worst-case scenarios. Adopting protective behaviors had substantial response costs, including adaptations for medical care and home support workers, threatened access to advance care, and increased caregiver burden. Participants expressed need for ALS-specific, pandemic information from trusted health professionals and/or ALS health charities. Telemedicine introduced both conveniences and costs. Prior experience with ALS provided tools for coping with Covid-19. Threat and coping appraisal was a dynamic process involving ongoing vigilance and adaptation. Findings draw attention to the lack of emergency preparedness among participants and within health systems.

CONCLUSIONS

Clinicians should engage ALS patients and families in ongoing discussions about pandemic coping, strategies to mitigate response costs, care pathways in the event of Covid-19 infection, and changing information about Covid-19 variants and vaccines. Healthcare systems should incorporate flexible approaches for medical care, leveraging the benefits of telemedicine and facilitating in-person interaction as needed and where possible. Research is needed to identify strategies to mitigate response costs and to further explore the interaction between prior experience and coping. Further study is also needed to determine how communication about emergency preparedness might be effectively incorporated into clinical care for those with ALS and other medically vulnerable populations.

Emerging technologies for management of patients with amyotrophic lateral sclerosis: from telehealth to assistive robotics and neural interfaces

Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease, is characterized by the degeneration of both upper and lower motor neurons, which leads to muscle weakness and subsequently paralysis. It begins subtly with focal weakness but spreads relentlessly to involve most muscles, thus proving to be effectively incurable. Typically, death due to respiratory paralysis occurs in 3–5 years. To date, it has been shown that the management of ALS patients is best achieved with a multidisciplinary approach, and with the help of emerging technologies ranging from multidisciplinary teleconsults (for monitoring the dysphagia, respiratory function, and nutritional status) to brain-computer interfaces and eye tracking for alternative augmentative communication, until robotics, it may increase effectiveness. The COVID-19 pandemic created a spasmodic need to accelerate the development and implementation of such technologies in clinical practice, to improve the daily lives of both ALS patients and caregivers. However, despite the remarkable strides that have been made in the field, there are still issues to be addressed. This review will be discussed on the eureka moment of emerging technologies for ALS, used as a blueprint not only for neurodegenerative diseases, examining the current technologies already in place or being evaluated, highlighting the pros and cons for future clinical applications.

A post pandemic roadmap toward remote assessment for neuromuscular disorders: limitations and opportunities

Recent advances in technology and expanding therapeutic opportunities in neuromuscular disorders has resulted in greater interest in and development of remote assessments. Over the past year, the rapid and abrupt COVID-19 shutdowns and stay-at-home orders imposed challenges to routine clinical management and clinical trials. As in-person services were severely limited, clinicians turned to remote assessments through telehealth to allow for continued care. Typically, disease-specific clinical outcome assessments (COAs) for neuromuscular disorders (NMD) are developed over many years through rigorous and iterative processes to fully understand their psychometric properties. While efforts were underway towards developing remote assessments for NMD before the pandemic, few if any were fully developed or validated. These included assessments of strength, respiratory function and patient-reported outcomes, as well as wearable technology and other devices to quantify physical activity and function. Without many choices, clinicians modified COAs for a virtual environment recognizing it was not yet known how they compared to standard in-person administration. Despite being able to quickly adapt to the demands of the COVID-19 pandemic, these experiences with remote assessments uncovered limitations and opportunities. It became clear that existing COAs required modifications for use in a virtual environment limiting the interpretation of the information gathered. Still, the opportunity for real-world evaluation and reduced patient burden were clear benefits to remote assessment and may provide a more robust understanding and characterization of disease impact in NMD. Hence, we propose a roadmap navigating an informed post-pandemic path toward development and implementation of safe and successful use of remote assessments for patients with NMD.

Recruitment of Patients With Amyotrophic Lateral Sclerosis for Clinical Trials and Epidemiological Studies: Descriptive Study of the National ALS Registry's Research Notification Mechanism

BACKGROUND

Researchers face challenges in patient recruitment, especially for rare, fatal diseases such as amyotrophic lateral sclerosis (ALS). These challenges include obtaining sufficient statistical power as well as meeting eligibility requirements such as age, sex, and study proximity. Similarly, persons with ALS (PALS) face difficulty finding and enrolling in research studies for which they are eligible.

OBJECTIVE

The aim of this study was to describe how the federal Agency for Toxic Substances and Disease Registry's (ATSDR) National ALS Registry is linking PALS to scientists who are conducting research, clinical trials, and epidemiological studies.

METHODS

Through the Registry's online research notification mechanism (RNM), PALS can elect to be notified about new research opportunities. This mechanism allows researchers to upload a standardized application outlining their study design and objectives, and proof of Institutional Review Board approval. If the application is approved, ATSDR queries the Registry for PALS meeting the study's specific eligibility criteria, and then distributes the researcher's study material and contact information to PALS via email. PALS then need to contact the researcher directly to take part in any research. Such an approach allows ATSDR to protect the confidentiality of Registry enrollees.

RESULTS

From 2013 to 2019, a total of 46 institutions around the United States and abroad have leveraged this tool and over 600,000 emails have been sent, resulting in over 2000 patients conservatively recruited for clinical trials and epidemiological studies. Patients between the ages of 60 and 69 had the highest level of participation, whereas those between the ages of 18 and 39 and aged over 80 had the lowest. More males participated (4170/7030, 59.32%) than females (2860/7030, 40.68%).

CONCLUSIONS

The National ALS Registry's RNM benefits PALS by connecting them to appropriate ALS research. Simultaneously, the system benefits researchers by expediting recruitment, increasing sample size, and efficiently identifying PALS meeting specific eligibility requirements. As more researchers learn about and use this mechanism, both PALS and researchers can hasten research and expand trial options for PALS.

Neuromuscular monitoring devices - where to go next?

PURPOSE OF REVIEW

This paper reviews the clinical applications, technology, and evidence supporting the use of telemedicine devices and telehealth in neuromuscular disease.

RECENT FINDINGS

The COVID-19 pandemic interrupted standard multidisciplinary care of patients with neuromuscular disease and created a need to adapt to remote care. Telemedicine applications were rapidly introduced and have rapidly proved an important tool in maintaining specialist care. This review presents the current data being gathered identifying the patients who benefit from telehealth applications, the appropriate type of telemedicine approach to specific conditions, the conditions needed to optimise telehealth approaches, and potential pitfalls and limitations in their use.

SUMMARY

Telemedicine is an important tool in providing robust remote care for patients with neuromuscular disorders, but further investigation is needed to optimise applications.

Telehealth approach for amyotrophic lateral sclerosis patients: the experience during COVID-19 pandemic

BACKGROUND AND OBJECTIVE

Specialized multidisciplinary ALS care has been shown to extend survival and improve patient's and caregiver's quality of life. During the COVID-19 pandemic, the management of patients suddenly changed and telemedicine has been proven to be as effective as outpatient care. We elaborate the experience with Telemedicine of a Tertiary ALS Center from an Italian geographical area with high infectious risk during the COVID-19 pandemic.

METHODS

19 patients were evaluated in telemedicine by a multidisciplinary team including a neurologist (clinical evaluation, intercurrent events, and drug prescriptions); a dietician (diet and weight monitoring); a psychologist (psychological assessment and support); and a physiotherapist (physiotherapy treatment and device prescription). Telemedicine was performed using the online platform "IoMT Connected Care Platform (Ticuro Reply)."

RESULTS

All patients reported a positive perception of talking face to face with healthcare professionals and were satisfied with how the team understood their problems. During video televisits, there was a change in the patient's medication regimen in 11/19; 2/19 required pneumological evaluation and started NIV; and 9/16 patients required prescription of devices. The mean monthly decline of ALSFRS-R before televisit was 0.88 (SD 1.17) and during televisit of 0.49 (SD 0.75). Bodyweight and daily caloric content remain stable. Reduction in HADS scores and stability in ALSAQ-40 were observed.

DISCUSSION

Our study positively reproduced the multidisciplinary approach currently used with ALS patients, trying to stabilize the functional and metabolic status and improving the psychological one. Future directions include a personalized telemedicine program according to the patient's needs.

COVID-19 and stroke-Understanding the relationship and adapting services. A global World Stroke Organisation perspective

A year ago the World Stroke Organisation (WSO) highlighted the enormous global impact of the COVID-19 pandemic on stroke care. In this review, we consider a year later where we are now, what the future holds, and what the long-term effects of the pandemic will be on stroke. Stroke occurs in about 1.4% of patients hospitalized with COVID-19 infection, who show an excess of large vessel occlusion and increased mortality. Despite this association, stroke presentations fell dramatically during the pandemic, although emerging data suggest that total stroke mortality may have risen with increased stroke deaths at home and in care homes. Strategies and guidelines have been developed to adapt stroke services worldwide, and protect healthcare workers. Adaptations include increasing use of telemedicine for all aspects of stroke care. The pandemic is exacerbating already marked global inequalities in stroke incidence and mortality. Lastly, the pandemic has had a major impact on stroke research and funding, although it has also emphasized the importance of large scale collaborative research initiatives.

Telehealth in Neurodegenerative Diseases: Opportunities and Challenges for Patients and Physicians

Telehealth, by definition, is distributing health-related services while using electronic technologies. This narrative Review describes the technological health services (telemedicine and telemonitoring) for delivering care in neurodegenerative diseases, Alzheimer's disease, Parkinson's Disease, and amyotrophic lateral Sclerosis, among others. This paper aims to illustrate this approach's primary experience and application, highlighting the strengths and weaknesses, with the goal of understanding which could be the most useful application for each one, in order to facilitate telehealth improvement and use in standard clinical practice. We also described the potential role of the COVID-19 pandemic to speed up this service's use, avoiding a sudden interruption of medical care.

Telehealth for Amyotrophic Lateral Sclerosis and Multiple Sclerosis

Amyotrophic lateral sclerosis and multiple sclerosis are neurodegenerative diseases requiring interdisciplinary rehabilitation services to maximize function, manage symptoms, prevent complications, and promote higher quality of life. Distance and disability may pose barriers to access of subspecialized care. Telehealth is one solution to facilitate access and was rapidly expanded during the COVID-19 pandemic. This article details the utility of telehealth services across the disease spectrum-including to establish a diagnosis, monitor progression for ongoing management, and identify and manage symptoms and provide therapy interventions. The challenges and promise of telehealth services for clinical care and research will be explored.

How to manage with telemedicine people with neuromuscular diseases?

INTRODUCTION

COVID-19 pandemic radically transformed our daily clinical practice, raising the need not to lose close contact with patients without being able to see them face-to-face. These issues are even more felt and evident in fragile patients, as those affected by neuromuscular disease. An important help came from new digital technologies that allow clinicians to remotely monitor health status and any deterioration of chronically ill patients.

METHODS

In this mini-review, an initiative of the "Digital Technologies, Web and Social Media Study Group" of the Italian Society of Neurology, we propose to analyze the approach to neuromuscular patients by looking over raising evidence on the main cornerstones of Telemedicine (TM): clinician-patient interaction, remote clinical assessment, remote monitoring, and digital therapeutics. In particular, we explored the strategies developed by researchers and their impact on the physical and emotional status of the patients, with particular focusing on their adherence to the program of virtual monitoring.

RESULTS

TM plays an important role in each of four stages of approach to neuromuscular disease, having demonstrated validity in keep close clinical patient interaction, clinical assessment, remote monitoring, and telerehabilitation. Nevertheless, there is no remote alternative to electrophysiological testing neither validate tools to assess disability.

CONCLUSION

The role of TM in neuromuscular care is yet underestimated but is crucial, beyond the pandemic era. Further development of TM is advisable, through making specific apps, remotely controlled by clinicians, and making more engaging clinicians-patients interaction. Last, it is necessary to ensure adequate internet access to everyone.

Development and validation of a machine-learning ALS survival model lacking vital capacity (VC-Free) for use in clinical trials during the COVID-19 pandemic

Introduction: Vital capacity (VC) is routinely used for ALS clinical trial eligibility determinations, often to exclude patients unlikely to survive trial duration. However, spirometry has been limited by the COVID-19 pandemic. We developed a machine-learning survival model without the use of baseline VC and asked whether it could stratify clinical trial participants and a wider ALS clinic population. Methods. A gradient boosting machine survival model lacking baseline VC (VC-Free) was trained using the PRO-ACT ALS database and compared to a multivariable model that included VC (VCI) and a univariable baseline %VC model (UNI). Discrimination, calibration-in-the-large and calibration slope were quantified. Models were validated using 10-fold internal cross validation, the VITALITY-ALS clinical trial placebo arm and data from the Emory University tertiary care clinic. Simulations were performed using each model to estimate survival of patients predicted to have a > 50% one year survival probability. Results. The VC-Free model suffered a minor performance decline compared to the VCI model yet retained strong discrimination for stratifying ALS patients. Both models outperformed the UNI model. The proportion of excluded vs. included patients who died through one year was on average 27% vs. 6% (VCI), 31% vs. 7% (VC-Free), and 13% vs. 10% (UNI). Conclusions. The VC-Free model offers an alternative to the use of VC for eligibility determinations during the COVID-19 pandemic. The observation that the VC-Free model outperforms the use of VC in a broad ALS patient population suggests the use of prognostic strata in future, post-pandemic ALS clinical trial eligibility screening determinations.