Early Referral to an ALS Center Reduces Several Months the Diagnostic Delay: A Multicenter-Based Study

Clinical and genetic factors affecting diagnostic timeline of amyotrophic lateral sclerosis: a 15-year retrospective study

OBJECTIVES

Amyotrophic Lateral Sclerosis (ALS) diagnosis can take 10-16 months from symptom onset, leading to delays in treatment and patient counselling. We studied the impact of clinical and genetic risk factors on the diagnostic timeline of ALS.

METHODS

Baseline characteristics, family history, gene testing, onset location, time from symptom onset to diagnosis, and time from first doctor visit to suspected ALS was collected. We used multiple regression to assess the interaction of these factors on ALS diagnostic timeline. We analysed a subgroup of patients with genetic testing and compared positive or negative tests, sporadic or familial and ALS-related genes to time for diagnosis.

RESULTS

Four hundred and forty-eight patients diagnosed with ALS at the University of Massachusetts Chan Medical Center between January 2007 and December 2021 were analysed. The median time to ALS diagnosis was 12 months and remained unchanged from 2007 to 2021 (p = 0.20). Diagnosis was delayed in patients with sporadic compared with familial ALS (mean months [standard deviation], 16.5[13.5] and 11.2[8.5], p < 0.001); cognitive onset (41[21.26]) had longer time to diagnosis than bulbar (11.9[8.2]), limb (15.9[13.2]), respiratory (19.7[13.9]) and ALS with multiple onset locations (20.77[15.71], p < 0.001). One hundred and thirty-four patients had gene testing and 32 tested positive (23.8%). Gene testing (p = 0.23), a positive genetic test (p = 0.16), different ALS genes (p = 0.25) and sporadic (p = 0.92) or familial (p = 0.85) ALS testing positive for ALS genes did not influence time to diagnosis.

DISCUSSION

Time for ALS diagnosis remained unchanged from 2007 to 2021, bulbar-onset and familial ALS made for faster diagnosis.

Racial disparities in ALS diagnostic delay: a single center's experience and review of potential contributing factors

OBJECTIVE

Outcomes for amyotrophic lateral sclerosis (ALS) patients are improved with prompt diagnosis, earlier initiation of disease-modifying treatments, and participation in a multidisciplinary clinic. We studied diagnostic delay and disease severity at time of clinic presentation between Black and non-Hispanic Caucasian ALS patients.

METHODS

We performed a retrospective analysis of non-Hispanic Caucasian and Black ALS patients seen in the Virginia Commonwealth University Health System multidisciplinary ALS clinic between 2017 and 2023. Diagnostic delay, ALS Functional Rating Scale-Revised (ALSFRS-R) and upright forced vital capacity (FVC) scores at baseline appointment were collected. Patient's distance from clinic and affluency of residential neighborhood were evaluated.

RESULTS

We analyzed 172 non-Hispanic Caucasian and 33 Black ALS patients. Black patients had a 64% increase in diagnostic delay compared to non-Hispanic Caucasian patients. Black patients had a lower performance on ALSFRS-R (5.3 points, p < 0.001) and FVC (17.9 percentage points p < 0.001) at time of first clinic visit. Black patients lived closer to clinic, with higher proportion living in the city of Richmond, but in less affluent areas with lower median house income ($55,300 ± 22,600 vs $69,900 ± 23,700).

DISCUSSION

Our findings demonstrate a large racial difference in ALS diagnostic delay, and greater disease severity and lower respiratory function at time of diagnosis for Black ALS patients. Delay in diagnosis prolongs access to disease-modifying therapies, multidisciplinary care, durable medical equipment, and respiratory and nutritional support. Potential sources of these racial disparities include providers' implicit bias and structural racism.

Misdiagnosis of amyotrophic lateral sclerosis in clinical practice in Europe and the USA: a patient chart review and physician survey

OBJECTIVE

Delays in amyotrophic lateral sclerosis (ALS) diagnosis can result in compromised disease management and unnecessary costs. We examined the extent of ALS misdiagnosis in the US and Europe.

METHODS

Data were collected via the Adelphi ALS Disease Specific Programme™, a cross-sectional survey of physicians and a medical chart review of their consulting patients with ALS in France, Germany, Italy, Spain, the UK (EU5), and the US. Between July 2020 and March 2021, eligible physicians (primary speciality neurology, active involvement in managing patients with ALS) abstracted data from patients (≥18 years old) with confirmed ALS.

RESULTS

Overall, 138 physicians completed the survey (EU5 107, US 31), with data reviewed from 795 patient medical charts (EU5 568, US 227); 278 (35.0%) patients (EU5 183 [32.2%], US 95 [41.9%]) had received ≥1 initial misdiagnosis based on symptoms later attributed to ALS. Mean (SD) time from symptom onset to first healthcare professional consultation was 3.8 (5.2) months (EU5 4.3 [4.8] months, US 2.6 [5.8] months). Mean (SD) time from symptom onset to ALS diagnosis was 8.2 (12.5) months (EU5 9.6 [14.0] months, US 5.0 [6.8] months) and increased to 10.4 (17.9) for patients with a misdiagnosis (compared with 6.9 [7.2] for patients with no misdiagnosis). Physician-identified barriers to timely ALS diagnosis included the similarity of symptoms to other conditions and delayed referral to neurologists.

CONCLUSIONS

Misdiagnosis of ALS is frequent, with a protracted diagnostic pathway. Targeted education of patients and physicians about signs and symptoms and benefits of prompt referral to multidisciplinary care are needed.

Diagnostic delay in amyotrophic lateral sclerosis

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a progressive, fatal neurodegenerative disease, and the time from symptom onset to diagnosis remains long. With the advent of disease-modifying treatments, the need to identify and diagnose ALS in a timely fashion has never been greater.

METHODS

We reviewed the literature to define the severity of ALS diagnostic delay, the various factors that contribute to this delay (including patient and physician factors), and the role that site of symptom onset plays in a patient's diagnostic journey.

RESULTS

Diagnostic delay is influenced by general practitioners' lack of recognition of ALS due to disease rarity and heterogenous presentations. As a result, patients are referred to non-neurologists, have unnecessary diagnostic testing, and may ultimately be misdiagnosed. Patient factors include their illness behavior-which impacts diagnostic delay-and their site of symptom onset. Limb-onset patients have the greatest diagnostic delay because they are frequently misdiagnosed with degenerative spine disease or peripheral neuropathy.

CONCLUSION

Prompt ALS diagnosis results in more effective clinical management, with earlier access to disease-modifying therapies, multidisciplinary care, and, if desired, clinical trial involvement. Due to lack of commercially available ALS biomarkers, alternative strategies to identify and triage patients who likely have ALS must be employed. Several diagnostic tools have been developed to encourage general practitioners to consider ALS and make an urgent referral to ALS specialists, bypassing unnecessary referrals to non-neurologists and unnecessary diagnostic workup.

Trends in the diagnostic delay and pathway for amyotrophic lateral sclerosis patients across different countries

Background

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative disease with a median survival of 2-5 years. An early diagnosis is essential for providing ALS patients the finest management possible. Studies from different countries report a similar median diagnostic delay of around 12 months, which is still far from desirable. We analyzed the diagnostic pathway in different countries in order to identify the major challenges.

Methods

We studied a cohort of 1,405 ALS patients from five different centers, in four different countries (Turkey, Germany, Poland, and Portugal), which collaborated in a common database. Demographic, disease and sociocultural factors were collected. Time from first symptom onset to first medical evaluation and to diagnosis, the specialist assessment and investigations requested were analyzed. Factors contributing to diagnostic delay were evaluated by multivariate linear regression.

Results

The median diagnostic delay from first symptom onset was 11 months and was similar between centers. Major differences were seen in the time from symptom onset to first medical evaluation. An earlier first medical evaluation was associated with a longer time to diagnosis, highlighting that ALS diagnosis is not straightforward in the early stages of the disease. The odds for ALS diagnosis were superior when evaluated by a neurologist and increased over time. Electromyography was decisive in establishing the diagnosis.

Conclusions

We suggest that a specific diagnostic test for ALS-a specific biomarker-will be needed to achieve early diagnosis. Early referral to a neurologist and to electromyography is important for early ALS diagnosis.

Symptoms timeline and outcomes in amyotrophic lateral sclerosis using artificial intelligence

Amyotrophic lateral sclerosis (ALS) is a fatal, neurodegenerative motor neuron disease. Although an early diagnosis is crucial to provide adequate care and improve survival, patients with ALS experience a significant diagnostic delay. This study aimed to use real-world data to describe the clinical profile and timing between symptom onset, diagnosis, and relevant outcomes in ALS. Retrospective and multicenter study in 5 representative hospitals and Primary Care services in the SESCAM Healthcare Network (Castilla-La Mancha, Spain). Using Natural Language Processing (NLP), the clinical information in electronic health records of all patients with ALS was extracted between January 2014 and December 2018. From a source population of all individuals attended in the participating hospitals, 250 ALS patients were identified (61.6% male, mean age 64.7 years). Of these, 64% had spinal and 36% bulbar ALS. For most defining symptoms, including dyspnea, dysarthria, dysphagia and fasciculations, the overall diagnostic delay from symptom onset was 11 (6-18) months. Prior to diagnosis, only 38.8% of patients had visited the neurologist. In a median post-diagnosis follow-up of 25 months, 52% underwent gastrostomy, 64% non-invasive ventilation, 16.4% tracheostomy, and 87.6% riluzole treatment; these were more commonly reported (all Ps < 0.05) and showed greater probability of occurrence (all Ps < 0.03) in bulbar ALS. Our results highlight the diagnostic delay in ALS and revealed differences in the clinical characteristics and occurrence of major disease-specific events across ALS subtypes. NLP holds great promise for its application in the wider context of rare neurological diseases.

Evaluating a general pediatric/adult genetic counseling clinic in a Midwest medical center

In 2018, the Munroe-Meyer Institute for Genetics & Rehabilitation (MMI) at the University of Nebraska Medical Center (UNMC) in Omaha, NE created a genetic counseling clinic (GCC) to increase access to genetics services and decrease the time spent between a referral and being seen in a general genetics outpatient clinic. In the GCC, genetic counselors led patient encounters and geneticists served as advisors, rather than primary providers. We conducted a chart review of 109 patients seen in the GCC from November 1, 2018, to March 16, 2020, and obtained information regarding patient demographics, indications, and clinical recommendations as a result of the visit. Most patients seen in this clinic were female (65.1%) and aged 19 years of age or older (54.1%). The primary indications for patients in this clinic included review genetic test results (42.2%), coordination of genetic testing for a known familial variant (30.2%), and concerns for personal or family history suspicious of a genetic condition without dysmorphic features (24.8%). The average patient wait time between referral date and appointment date in the GCC was 49.8 days. The two most common clinical recommendations made by genetic counselors in the GCC were genetic testing (56.1%) and/or follow-up with specialist (26.5%). These specialists primarily included endocrinology (n = 5), neurology (n = 4), cardiology (n = 4), ophthalmology (n = 3), and audiology (n = 3). We found that the GCC model may be appropriate for patients with (1) genetic test results requiring interpretation, (2) a known familial variant or (3) genetic testing recommended by a specialist physician. Descriptions of the indications and recommendations for patients seen in this GCC provide a framework for potential implementation of a GCC in other regions across the nation.

Effect of neurofilament analysis on the diagnostic delay in amyotrophic lateral sclerosis

AIMS

The aim of this study was to investigate whether neurofilament light (NfL) and phosphorylated neurofilament heavy (pNfH) in cerebrospinal fluid (CSF), sampled prior to referral to a neuromuscular reference center (NMRC), shorten the diagnostic delay in patients with amyotrophic lateral sclerosis.

METHODS

In this retrospective study, patients with ALS were included with (i) determination of neurofilaments (Nfs) before referral to the NMRC (preC-Nfs ALS, n = 58), (ii) determination of Nfs at the NMRC (C-Nfs, n = 54) or (iii) with no determination of Nfs (C-No Nfs, n = 180). Fifty-six disease controls were included.

RESULTS

The preC-Nfs cohort had CSF sampled 2.2 months (range: 0.6-12.0 months) before referral to the NMRC. In this cohort, the diagnostic delay was significantly shorter [median (range): 8.24 (2.37-49.7) months] than in the C-Nfs cases [median (range): 11.4 (2.93-86.5) months; p < 0.05], but not in the C-No Nfs cases. When including the disease progression rate and the presence of a genetic mutation as covariates, the difference ceased to exist (p = 0.14). pNfH and NfL levels in the preC-Nfs cohort were significantly higher than in disease controls (p < 0.0001). Both Nfs showed a similar discriminating performance.

CONCLUSIONS

CSF Nfs assessed before the diagnosis of ALS at a NMRC decreased the diagnostic delay in specific cases by 3 months and only when other covariates were not taken into account.

Hastening the Diagnosis of Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a chronic progressive neurodegenerative disease. Neurologists generally see patients as requested and as schedules allow. This practice is part of the reason it takes approximately 12 months from onset of new progressive weakness to receive a definitive diagnosis of ALS. It is well recognized that the disease of ALS starts long before symptom onset. In mutant SOD1 transgenic mice, early loss of motor neurons and compensatory morphological changes precede a rapid loss of motor neurons that coincides with symptom onset. In a human autopsy study, anterior roots in the "presymptomatic" stage indicate that ∼20% loss of motor neurons had already occurred. Sera collected from individuals who later developed ALS and sera from presymptomatic members of families with ALS harboring pathogenic gene variants demonstrated high neurofilament (Nf) levels, again suggesting that the neurodegenerative process is already active at a clinically presymptomatic stage. Potential benefits of hastening the diagnosis of ALS include earlier initiation of therapy to slow the fundamental neurodegenerative process. Such effects are observed in treatment with riluzole, edaravone, methylcobalamin, and sodium phenylbutyrate-taurursodiol in patient care and clinical trial settings. Early initiation of multidisciplinary care results in cost savings and prolonged survival. Early diagnosis after symptom onset also seems to reduce psychological distress. Hence, how can we facilitate an earlier diagnosis of ALS? We already have the necessary tools. New and simple ALS diagnostic criteria (Gold Coast Criteria) have been introduced along with genetic testing. At least 2 studies provide Class II evidence that establishes the reliability and sensitivity of CSF and/or serum Nf levels in supporting a diagnosis of ALS. Challenges, however, still exist as to how to facilitate earlier recognition of possible ALS by primary care physicians and other nonneurologist providers and how to foster a sense of urgency among neurologists to accelerate the diagnostic process. In this article, we provide a number of recommendations that we hope will help achieve these ends.

Pathophysiological Underpinnings of Extra-Motor Neurodegeneration in Amyotrophic Lateral Sclerosis: New Insights From Biomarker Studies

Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) lie at opposing ends of a clinical, genetic, and neuropathological continuum. In the last decade, it has become clear that cognitive and behavioral changes in patients with ALS are more frequent than previously recognized. Significantly, these non-motor features can impact the diagnosis, prognosis, and management of ALS. Partially overlapping neuropathological staging systems have been proposed to describe the distribution of TAR DNA-binding protein 43 (TDP-43) aggregates outside the corticospinal tract. However, the relationship between TDP-43 inclusions and neurodegeneration is not absolute and other pathophysiological processes, such as neuroinflammation (with a prominent role of microglia), cortical hyperexcitability, and synaptic dysfunction also play a central role in ALS pathophysiology. In the last decade, imaging and biofluid biomarker studies have revealed important insights into the pathophysiological underpinnings of extra-motor neurodegeneration in the ALS-FTLD continuum. In this review, we first summarize the clinical and pathophysiological correlates of extra-motor neurodegeneration in ALS. Next, we discuss the diagnostic and prognostic value of biomarkers in ALS and their potential to characterize extra-motor neurodegeneration. Finally, we debate about how biomarkers could improve the diagnosis and classification of ALS. Emerging imaging biomarkers of extra-motor neurodegeneration that enable the monitoring of disease progression are particularly promising. In addition, a growing arsenal of biofluid biomarkers linked to neurodegeneration and neuroinflammation are improving the diagnostic accuracy and identification of patients with a faster progression rate. The development and validation of biomarkers that detect the pathological aggregates of TDP-43 in vivo are notably expected to further elucidate the pathophysiological underpinnings of extra-motor neurodegeneration in ALS. Novel biomarkers tracking the different aspects of ALS pathophysiology are paving the way to precision medicine approaches in the ALS-FTLD continuum. These are essential steps to improve the diagnosis and staging of ALS and the design of clinical trials testing novel disease-modifying treatments.

Delayed Diagnosis and Diagnostic Pathway of ALS Patients in Portugal: Where Can We Improve?

Background: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease with unsatisfactory treatment options. Best management and recruitment into clinical trials requires early diagnosis. However, diagnosis is often delayed. Analysis of the diagnostic pathway and identification of the causes of diagnostic delay are imperative. Methods: We studied a cohort of 580 ALS patients followed up in our ALS clinic in Lisbon. Demographic, disease, and sociocultural factors were collected. Time from first symptom onset to diagnosis, the specialist's assessment, and investigations requested were analyzed. Predictors of diagnostic delay were evaluated by multivariate linear regression, adjusting for potential confounders. Results: The median diagnostic delay from first symptom onset was 10 months. Spinal-onset, slower disease progression, cognitive symptoms at onset, and lower income were associated with increased diagnostic delay. Most patients were first assessed by general practitioners. Patients who were first evaluated by a neurologist were more likely to be correctly diagnosed, decreasing time to diagnosis. Electromyography was decisive in establishing the diagnosis. Conclusions: Late referral from non-neurologists to a neurologist is a potentially modifiable factor contributing to significant diagnostic delay. Educational interventions targeted to non-neurologists physicians, in order to increase awareness of ALS and, consequently, promote early referral to a neurologist at a tertiary center, will be important in reducing diagnostic delay.

Facilitations and Hurdles of Genetic Testing in Neuromuscular Disorders

Neuromuscular disorders (NMDs) comprise a heterogeneous group of disorders that affect about one in every thousand individuals worldwide. The vast majority of NMDs has a genetic cause, with about 600 genes already identified. Application of genetic testing in NMDs can be useful for several reasons: correct diagnostic definition of a proband, extensive familial counselling to identify subjects at risk, and prenatal diagnosis to prevent the recurrence of the disease; furthermore, identification of specific genetic mutations still remains mandatory in some cases for clinical trial enrollment where new gene therapies are now approaching. Even though genetic analysis is catching on in the neuromuscular field, pitfalls and hurdles still remain and they should be taken into account by clinicians, as for example the use of next generation sequencing (NGS) where many single nucleotide variants of “unknown significance” can emerge, complicating the correct interpretation of genotype-phenotype relationship. Finally, when all efforts in terms of molecular analysis have been carried on, a portion of patients affected by NMDs still remain “not genetically defined”. In the present review we analyze the evolution of genetic techniques, from Sanger sequencing to NGS, and we discuss “facilitations and hurdles” of genetic testing which must always be balanced by clinicians, in order to ensure a correct diagnostic definition, but taking always into account the benefit that the patient could obtain especially in terms of “therapeutic offer”.

Facilitations and Hurdles of Genetic Testing in Neuromuscular Disorders

Neuromuscular disorders (NMDs) comprise a heterogeneous group of disorders that affect about one in every thousand individuals worldwide. The vast majority of NMDs has a genetic cause, with about 600 genes already identified. Application of genetic testing in NMDs can be useful for several reasons: correct diagnostic definition of a proband, extensive familial counselling to identify subjects at risk, and prenatal diagnosis to prevent the recurrence of the disease; furthermore, identification of specific genetic mutations still remains mandatory in some cases for clinical trial enrollment where new gene therapies are now approaching. Even though genetic analysis is catching on in the neuromuscular field, pitfalls and hurdles still remain and they should be taken into account by clinicians, as for example the use of next generation sequencing (NGS) where many single nucleotide variants of "unknown significance" can emerge, complicating the correct interpretation of genotype-phenotype relationship. Finally, when all efforts in terms of molecular analysis have been carried on, a portion of patients affected by NMDs still remain "not genetically defined". In the present review we analyze the evolution of genetic techniques, from Sanger sequencing to NGS, and we discuss "facilitations and hurdles" of genetic testing which must always be balanced by clinicians, in order to ensure a correct diagnostic definition, but taking always into account the benefit that the patient could obtain especially in terms of "therapeutic offer".