Burden and preparedness of care partners of people living with amyotrophic lateral sclerosis at home in Korea: A care partner survey

INTRODUCTION/AIMS

The care burden of people living with amyotrophic lateral sclerosis (pALS) increases with disease progression. This study aimed to investigate the home care status and preparedness of care partners of pALS (cALS) in Korea.

METHODS

An online survey was conducted with family care partners of patients diagnosed with ALS for over 1 year in 2022. The data collected included care time, depression evaluated using the patient health questionnaire-9 (PHQ-9), preparedness for caregiving scale (PCS), and caregiver competence scale (CCS). Results were compared based on whether the pALS underwent a tracheostomy or not.

RESULTS

Ninety-eight cALS of 98 pALS participated in the study, of whom 59 pALS had undergone tracheostomy. Among the cALS, 60.2% were spouses, and 34.7% were children. The cALS took care of the patients for 13 (8-20) hours/day (median, interquartile range [IQR]) on weekdays and 15 (10-24) h/day on weekends. Among the cALS, 91.8% were depressed, and 28.6% had severe depression. The median (IQR) PCS and CCS scores were low (11/32 (8-15) and 8/20 (8-11), respectively), and both were lower in those caring for patients without than with tracheostomy (p < .001 and p < .02, respectively). Most cALS (77.6%) wished to continue caring for their pALS at home.

DISCUSSION

Family care partners of pALS spend more than half of each day caring for patients and are often depressed. Most cALS preferred providing care at home, but felt ill-prepared. Designing home-based medical care is necessary for pALS to thrive at home.

Factors associated with adherence to noninvasive positive pressure ventilation in amyotrophic lateral sclerosis

INTRODUCTION

This cohort study aimed to investigate the factors associated with noninvasive positive pressure ventilation adherence and assess the long-term effects of noninvasive positive pressure ventilation adherence in patients with amyotrophic lateral sclerosis (ALS).

METHODS

The medical records of patients with ALS admitted to a tertiary hospital for noninvasive positive pressure ventilation initiation were retrospectively reviewed. Pulmonary function parameters, variables of blood gas analysis, the site of symptom onset, the time from onset and diagnosis to noninvasive positive pressure ventilation application, ALS Functional Rating Scale-Revised, neurophysiological index, and the length of hospital stay were evaluated. The adherence to noninvasive positive pressure ventilation was defined as the use of noninvasive positive pressure ventilation for ≥ 2 h/day or ≥ 4 h/day. The correlations between noninvasive positive pressure ventilation adherence or length of hospital stay and other clinical parameters were analyzed.

RESULTS

Fifty-one patients with ALS were included in the study. The time from onset and diagnosis to NIPPV application was reduced by 16 months in the adherent group than that in the non-adherent group; however, the parameters of blood gas analysis and pulmonary function tests did not differ significantly between the groups. Furthermore, the neurophysiological index of the abductor digiti minimi muscle was higher by 4.05 in the adherent group than that in the non-adherent group. The adherence to noninvasive positive pressure ventilation prolonged tracheostomy-free survival compared to that of non-adherence. Desaturation events, lower forced vital capacity, last pCO2, bicarbonate, and base excess, and higher differences in pCO2, were associated with an increase in the length of hospital stay.

CONCLUSIONS

Noninvasive positive pressure ventilation application shortly after symptom onset and ALS diagnosis in patients with CO2 retention and reduced forced vital capacity can be considered for successful adherence. Adherence to noninvasive positive pressure ventilation may result in reduced tracheostomy conversion rates and prolonged tracheostomy-free survival.

Prognosis of amyotrophic lateral sclerosis patients after tracheostomy invasive ventilation in Korea

Background: Tracheostomy invasive ventilation (TIV) is applied to a subset of amyotrophic lateral sclerosis (ALS) patients; however, its frequency and impact on prognosis vary across countries. Methods: We conducted a nationwide retrospective cohort study using Korean National Health Insurance claims data. All patients diagnosed with sporadic ALS from 2012 to 2017 were included, with the observation period until 2020. The survival time between the TIV and non-TIV groups was compared using propensity score matching analysis, and prognostic factors were assessed within the TIV group. Results: This study included 3484 ALS patients (mean [standard deviation] age, 62.4 [11.9] years, 60.4% male), among whom 1230 (35.3%) underwent TIV. After 1:1 propensity score matching, the survival duration between the two groups was not significantly different (28 vs. 25 months, p = 0.057). Cox regression indicated that older age (hazard ratios [HRs] for each decade compared to <40 years: 3.89, 3.83, 5.30, 6.78, and 8.40 [≥ 80 years]; p < 0.005 for all) and lower income (HR, 1.28; 95% confidence interval [CI], 1.09-1.52; p = 0.003) negatively impacted survival, while gastrostomy (HR, 0.57; 95% CI, 0.50-0.66; p < 0.001) and supportive care services (HR, 0.43; 95% CI, 0.32-0.59; p < 0.001) were associated with prolonged survival. Conclusions: TIV was administered to more than one-third of Korean ALS patients without significant survival prolongation. Older age, lower income, lack of gastrostomy, and insufficient supportive care were independent poor prognostic factors for survival, underscoring the importance of comprehensive management for ALS patients.

Healthcare Utilization and Supportive Care Timing in South Korean People Living With Amyotrophic Lateral Sclerosis: A Single-Center Retrospective Study

BACKGROUND AND PURPOSE

Despite the growing demands and challenges faced by patients with amyotrophic lateral sclerosis (ALS) in accessing healthcare services, our understanding of this access remains poor. This study aimed to investigate the healthcare utilization patterns and timing of nutritional and respiration support in patients with ALS in South Korea.

METHODS

A retrospective cohort study was conducted on patients diagnosed with ALS at a single tertiary hospital between 2016 and 2019 and followed up for 2 years. We evaluated patient characteristics, healthcare utilization (hospital admissions, outpatient visits, and emergency department [ED] visits), and the timing of nutritional and respiration support (noninvasive positive pressure ventilation [NIPPV], tracheostomy, gastrostomy, and nasogastric tube) at 6-month intervals from the first outpatient visit.

RESULTS

Among the 143 included patients, 73.4% were admitted at least once, 18.9% experienced unplanned admissions, and 30.1% visited the ED at least once during the study period. The most-common reason for ED visits was neurological symptoms during the first 6 months (59.1%), followed by respiratory symptoms. One fifth of patients who visited the ED underwent tracheostomy (20.9%) or NIPPV (20.9%). Two years after the first visit, 32.2% used a ventilator, and 13.3%, 26.6%, and 6.3% had undergone tracheostomy, gastrostomy, and nasogastric tube insertion, respectively.

CONCLUSIONS

During the 2 years following their first outpatient visit, 20% of patients with ALS experienced unplanned admissions and 30% visited the ED. An active and prompt supportive-care program should be implemented to ensure timely functional support in order to reduce these risks of unplanned admissions.

Effect of altered gene expression in lipid metabolism on cognitive improvement in patients with Alzheimer's dementia following fecal microbiota transplantation: a preliminary study

Background

The brain-gut axis has emerged as a potential target in neurodegenerative diseases, including dementia, as individuals with dementia exhibit distinct gut microbiota compositions. Fecal microbiota transplantation (FMT), the transfer of fecal solution from a healthy donor to a patient, has shown promise in restoring homeostasis and cognitive enhancement.

Objective

This study aimed to explore the effects of FMT on specific cognitive performance measures in Alzheimer's dementia (AD) patients and investigate the relationship between cognition and the gut microbiota by evaluating changes in gene expression following FMT.

Methods

Five AD patients underwent FMT, and their cognitive function [Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and Clinical Dementia Rating Scale Sum of Boxes (CDR-SOB)] was assessed before and after FMT. The patients' fecal samples were analyzed with 16S rRNA to compare the composition of their gut microbiota. We also assessed modifications in the serum mRNA expression of patients' genes related to lipid metabolism using serum RNA sequencing and quantitative real-time polymerase chain reaction.

Results

Significant improvements in cognitive function, as measured by the MMSE (pre- and post-FMT was 13.00 and 18.00) and MoCA were seen. The MoCA scores at 3 months post-FMT (21.0) were the highest (12.0). The CDR-SOB scores at pre- and post-FMT were 10.00 and 5.50, respectively. Analysis of the gut microbiome composition revealed changes via 16S rRNA sequencing with an increase in Bacteroidaceae and a decrease in Enterococcaceae. Gene expression analysis identified alterations in lipid metabolism-related genes after FMT.

Conclusion

These findings suggest a link between alterations in the gut microbiome, gene expression related to lipid metabolism, and cognitive function. The study highlights the importance of gut microbiota in cognitive function and provides insights into potential biomarkers for cognitive decline progression. FMT could complement existing therapies and show potential as a therapeutic intervention to mitigate cognitive decline in AD.

Therapeutic Outcomes and Electrophysiological Biomarkers in Anti-Myelin-Associated Glycoprotein Neuropathy: A Multicenter Cohort Study in South Korea

BACKGROUND AND PURPOSE

Unlike other immune-mediated neuropathies, anti-myelin-associated glycoprotein (MAG) neuropathy is often refractory to immunotherapy. It is necessary to compare the relative efficacies of various immunotherapies and develop objective biomarkers in order to optimize its clinical management.

METHODS

This study recruited 91 patients with high anti-MAG antibody titers from 7 tertiary hospitals in South Korea. We analyzed the baseline characteristics, therapeutic outcomes, and nerve conduction study (NCS) findings of 68 patients and excluded 23 false positive cases.

RESULTS

The rate of positive responses to treatment was highest using zanubrutinib (50%) and rituximab (36.4%), followed by corticosteroids (16.7%), immunosuppressants (9.5%), intravenous immunoglobulin (5%), and plasma exchange (0%). Disability and weakness were significantly associated with multiple NCS parameters at the time of diagnosis, especially distal compound muscle action potential (CMAP) amplitudes. Moreover, the longitudinal trajectory of the average CMAP amplitudes paralleled the clinical courses, with a 16.2 percentile decrease as an optimal cutoff for predicting a clinical exacerbation (area under the receiver operating characteristic curve=0.792).

CONCLUSIONS

Our study supports the use of NCS as an objective marker for estimating disease burden and tracking clinical changes in patients with anti-MAG neuropathy. We have described the beneficial effects of rituximab and a new drug, zanubrutinib, compared with conventional immunotherapies.

Association Between Fat Depletion and Prognosis of Amyotrophic Lateral Sclerosis: CT-Based Body Composition Analysis

OBJECTIVE

The purpose of this study was to present the results of our investigation of the prognostic value of adipopenia and sarcopenia in patients with amyotrophic lateral sclerosis (ALS).

METHODS

Consecutive patients with ALS with abdominal computed tomography (CT) were retrospectively identified at a single tertiary hospital between January 2010 and July 2021. Deep learning-based volumetric CT body composition analysis software was used to obtain abdominal waist fat volume, fat attenuation, and skeletal muscle area at the L3 level, then normalized to the fat volume index (FVI) and skeletal muscle index (SMI). Adipopenia and sarcopenia were defined as the sex-specific lowest quartile and SMI reference values, respectively. The associations of CT-derived body composition parameters with clinical variables, such as body mass index (BMI) and creatinine, were evaluated by Pearson correlation analyses, and associations with survival were assessed using the multivariable Cox regression analysis.

RESULTS

Eighty subjects (40 men, 65.5 ± 9.4 years of age) were investigated (median interval between disease onset and CT examination = 25 months). The mean BMI at the CT examination was 20.3 ± 4.3 kg/m2 . The BMI showed a positive correlation with both FVI (R = 0.70, p < 0.001) and SMI (R = 0.63, p < 0.001), and the serum creatinine level was associated with SMI (R = 0.68, p < 0.001). After adjusting for sex, age, King's stage, BMI, creatinine, progression rate, and sarcopenia, adipopenia was associated with shorter survival (hazard ratio [HR] = 5.94, 95% confidence interval [CI] = 1.01, 35.0, p = 0.049). In a subgroup analysis for subjects with nutritional failure (stage 4a), the HR of adipopenia was 15.1 (95% CI = 2.45, 93.4, p = 0.003).

INTERPRETATION

Deep learning-based CT-derived adipopenia in patients with ALS is an independent poor prognostic factor for survival. ANN NEUROL 2023;94:1116-1125.

Subclinical articulatory changes of vowel parameters in Korean amyotrophic lateral sclerosis patients with perceptually normal voices

The available quantitative methods for evaluating bulbar dysfunction in patients with amyotrophic lateral sclerosis (ALS) are limited. We aimed to characterize vowel properties in Korean ALS patients, investigate associations between vowel parameters and clinical features of ALS, and analyze subclinical articulatory changes of vowel parameters in those with perceptually normal voices. Forty-three patients with ALS (27 with dysarthria and 16 without dysarthria) and 20 healthy controls were prospectively collected in the study. Dysarthria was assessed using the ALS Functional Rating Scale-Revised (ALSFRS-R) speech subscores, with any loss of 4 points indicating the presence of dysarthria. The structured speech samples were recorded and analyzed using Praat software. For three corner vowels (/a/, /i/, and /u/), data on the vowel duration, fundamental frequency, frequencies of the first two formants (F1 and F2), harmonics-to-noise ratio, vowel space area (VSA), and vowel articulation index (VAI) were extracted from the speech samples. Corner vowel durations were significantly longer in ALS patients with dysarthria than in healthy controls. The F1 frequency of /a/, F2 frequencies of /i/ and /u/, the VSA, and the VAI showed significant differences between ALS patients with dysarthria and healthy controls. The area under the curve (AUC) was 0.912. The F1 frequency of /a/ and the VSA were the major determinants for differentiating ALS patients who had not yet developed apparent dysarthria from healthy controls (AUC 0.887). In linear regression analyses, as the ALSFRS-R speech subscore decreased, both the VSA and VAI were reduced. In contrast, vowel durations were found to be rather prolonged. The analyses of vowel parameters provided a useful metric correlated with disease severity for detecting subclinical bulbar dysfunction in ALS patients.

Epidemiology and characteristics of emergency department utilization by patients with amyotrophic lateral sclerosis in Korea from 2016 to 2020: A nationwide study

INTRODUCTION/AIMS

Patients with amyotrophic lateral sclerosis (ALS) inevitably visit the emergency department (ED) due to their increased risk of respiratory failure and mobility limitations. However, nationwide data on ED visits by patients with ALS are limited. This study investigated the characteristics of patients with ALS-related ED visits.

METHODS

We conducted a cross-sectional study from 2016 to 2020, utilizing a nationwide ED database. The total number of patients with ALS who visited the ED and their primary reasons for visiting/diagnoses were analyzed.

RESULTS

In total, 6036 visits to the ED were made by patients with ALS. Of these, 41.8% arrived by ambulance and 27.7% spent >9 h in the ED. Following ED treatment, 57.4% were hospitalized, including 19.3% admitted to the intensive care unit (ICU) and 5.4% who died in the hospital. The primary reasons for ALS-related ED visits were dyspnea (35.2%), feeding tube problems (10.1%), fever (7.8%), and mental status changes (3.6%). The most common diagnoses were pneumonia (14.5%), respiratory failure (5.7%), dyspnea (5.5%), aspiration pneumonia (4.3%), and tracheostomy complications (3.4%).

DISCUSSION

Reasons for ED visits for patients with ALS include acute respiratory distress, as well as concerns related to tube feeding and tracheostomy. To reduce the risk of patients with ALS requiring ED visits, it is essential to ensure the provision of timely respiratory support and high-quality home-based medical care teams that can support and address patients before their condition deteriorates.

Suicide Attempts in Patients With Amyotrophic Lateral Sclerosis: An Analysis of the Korean National Health Insurance Database

Objective: The knowledge of the common risk factors for suicide attempts may not be simply applicable to patients with amyotrophic lateral sclerosis (ALS). We aimed to identify risk factors associated with suicide attempts in patients with ALS and to determine the annual prevalence and periods of vulnerability associated with attempts.

Methods: This nationwide cohort study was performed using the Korean National Health Insurance Database. All patients with ALS concomitantly registered for the Exempted Calculation of Health Insurance for rare, incurable diseases between 2011 and 2017 were identified. We used the Cox proportional hazards regression model and competing risk model to identify the risk factors for suicide attempts. The multivariable models were adjusted for potential risk factors from the univariate analysis.

Results: Among 2,955 incident patients, 47 attempted suicide. After adjusting for sex, previous attempts, and previous psychiatric disorders, the hazard ratios for psychiatric hospitalization before ALS diagnosis were 3.17 (95% confidence interval [CI], 1.31-7.70; P = .01) and 3.02 (95% CI, 1.32-6.90; P = .01) in the Cox regression model and the competing risk model, respectively. The annual prevalence of suicide attempts was 0.29%-1.12%. Twenty (42.6%) and 9 (19.1%) attempts occurred within 3 months and 12-18 months after diagnosis, respectively.

Conclusions: Psychiatric hospitalization increased the risk of suicide attempts, which clustered at the early stage or on losing autonomy. Those with a history of psychiatric hospitalization should receive an in-depth evaluation and be cautiously monitored.

Development and Validation of the Korean Version of the Edinburgh Cognitive and Behavioral Amyotrophic Lateral Sclerosis Screen (ECAS-K)

BACKGROUND AND PURPOSE

Cognitive and behavioral changes are common in amyotrophic lateral sclerosis (ALS), with about 15% of patients presenting with overt frontotemporal dementia and 30%-50% with varying degrees of impairments. We aimed to develop and validate the Korean version of the Edinburgh Cognitive and Behavioral ALS Screen (ECAS-K), a brief multidomain assessment tool developed for ALS patients with physical disability.

METHODS

We developed the ECAS-K according to the translation guidelines, and administered it to 38 patients with ALS and 26 age- and education-level-matched controls. We also administered the Montreal Cognitive Assessment (MoCA) and Frontal Assessment Battery (FAB) to investigate convergent validity, and the Center for Neurologic Study-Liability Scale to assess the association between pseudobulbar affect and cognitive/behavioral changes.

RESULTS

Internal consistency among the ECAS-K test items was found to be high, with a Cronbach's alpha of 0.87. Significant differences were found between patients with ALS and the controls in language, fluency, and memory functions (p<0.05). Abnormal performance based on the ECAS total score was noted in 39.4% of patients, and 66.6% presented behavioral changes in at least one domain. Significant correlations were observed between the scores of the ECAS-K and those of other cognitive screening tools (MoCA and FAB, with correlation coefficients of 0.69 and 0.55, respectively; p<0.01).

CONCLUSIONS

We developed and validated the ECAS-K which could be used as an effective tool to screen the cognitive and behavioral impairments in Korean patients with ALS.

AXL+SIGLEC6+ dendritic cells in cerebrospinal fluid and brain tissues of patients with autoimmune inflammatory demyelinating disease of CNS

Inflammatory demyelinating disease of the CNS (IDD) is a heterogeneous group of autoimmune diseases, and multiple sclerosis is the most common type. Dendritic cells (DCs), major antigen-presenting cells, have been proposed to play a central role in the pathogenesis of IDD. The AXL+SIGLEC6+ DC (ASDC) has been only recently identified in humans and has a high capability of T cell activation. Nevertheless, its contribution to CNS autoimmunity remains still obscure. Here, we aimed to identify the ASDC in diverse sample types from IDD patients and experimental autoimmune encephalomyelitis (EAE). A detailed analysis of DC subpopulations using single-cell transcriptomics for the paired cerebrospinal fluid (CSF) and blood samples of IDD patients (total n = 9) revealed that three subtypes of DCs (ASDCs, ACY3+ DCs, and LAMP3+ DCs) were overrepresented in CSF compared with their paired blood. Among these DCs, ASDCs were also more abundant in CSF of IDD patients than in controls, manifesting poly-adhesional and stimulatory characteristics. In the brain biopsied tissues of IDD patients, obtained at the acute attack of disease, ASDC were also frequently found in close contact with T cells. Lastly, the frequency of ASDC was found to be temporally more abundant in acute attack of disease both in CSF samples of IDD patients and in tissues of EAE, an animal model for CNS autoimmunity. Our analysis suggests that the ASDC might be involved in the pathogenesis of CNS autoimmunity.

Small RNA sequencing of circulating small extracellular vesicles microRNAs in patients with amyotrophic lateral sclerosis

Dysregulation of microRNAs (miRNA) in small extracellular vesicles (sEV) such as exosomes have been implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS). Although circulating cell-free miRNA have been extensively investigated in ALS, sEV-derived miRNAs have not been systemically explored yet. Here, we performed small RNA sequencing analysis of serum sEV and identified 5 differentially expressed miRNA in a discovery cohort of 12 patients and 11 age- and sex-matched healthy controls (fold change > 2, p < 0.05). Two of them (up- and down-regulation of miR-23c and miR192-5p, respectively) were confirmed in a separate validation cohort (18 patients and 15 healthy controls) by droplet digital PCR. Bioinformatic analysis revealed that these two miRNAs interact with distinct sets of target genes and involve biological processes relevant to the pathomechanism of ALS. Our results suggest that circulating sEV from ALS patients have distinct miRNA profiles which may be potentially useful as a biomarker of the disease.

Clinical pitfalls and serological diagnostics of MuSK myasthenia gravis

BACKGROUND

We aimed to evaluate the diagnostic accuracy of enzyme-linked immunosorbent assay (ELISA) for anti-muscle specific tyrosine kinase (MuSK) antibody (Ab) in a large cohort of anti-acetylcholine receptor (AChR) Ab-negative generalized myasthenia gravis (MG), and also to investigate clinical contexts for the diagnosis of MuSK MG.

METHODS

A retrospective study of 160 patients with a clinical suspicion of AChR Ab-negative generalized MG was performed. The serum samples were tested for anti-clustered AChR Ab by cell-based assay (CBA), anti-MuSK Ab by ELISA, CBA and/or radioimmunoprecipitation assay (RIPA). Clinical data were compared between anti-MuSK Ab-positive MG and double seronegative (AChR and MuSK) MG groups.

RESULTS

After excluding non-MG and clustered AChR Ab-positive patients, we identified 89 patients as a cohort of AChR Ab-negative generalized MG. Anti-MuSK Ab was positive by ELISA in 22 (24.7%) patients. While CBA identified five additional anti-MuSK Ab-positive patients, the results of ELISA were mostly consistent with CBA and RIPA with Cohen's kappa of 0.80 and 0.90, respectively (p < 0.001). The most frequent differential diagnosis was motor neuron disease particularly of bulbar onset which showed remarkably overlapping clinical and electrophysiological features with MuSK MG at presentation.

CONCLUSION

While confirming the highest sensitivity of CBA for detecting anti-MuSK Ab, our results highlight the clinical pitfalls in making a diagnosis of MuSK MG and may support a diagnostic utility of MuSK-ELISA in clinical practice.

National prescription patterns of antidepressants among patients with amyotrophic lateral sclerosis: an analysis of the Korean National Health Insurance database

INTRODUCTION/AIMS

The current status of antidepressant use in patients with amyotrophic lateral sclerosis (ALS), such as the prevalence and factors associated with it, has not been systematically investigated. We aimed to analyze the prevalence and patterns of antidepressant prescriptions in patients with ALS and depression, and to identify factors associated with antidepressant prescriptions following the diagnosis of ALS.

METHODS

The data of patients with ALS and the prescription of antidepressants were retrieved from the Korean National Health Insurance claims data. A multivariate logistic regression model was used to identify factors associated with antidepressant prescriptions.

RESULTS

In total, 533 of 2,955 patients had depressive disorders, and 426 were prescribed antidepressants. Selective serotonin reuptake inhibitors and tricyclic antidepressants were the most frequently prescribed drugs. Adjusted odds ratios (ORs) were 1.379 for the prescription of antidepressants in females. For various age groups, compared with those aged 80 years and older, adjusted ORs were 1.889 for those in their 70s, 2.319 for those in their 60s, 2.872 for those in their 50s, 2.854 for those in their 40s, and 3.363 for those under 40 years of age. Adjusted ORs were 1.662 for patients with a history of a psychiatric disorder and 1.861 for those with a history of psychiatric pharmacotherapy (all p < 0.05).

DISCUSSION

Most patients with ALS who had depression received antidepressant prescriptions. In young females with a previous psychiatric disorder or pharmacotherapy, an in-depth evaluation for a depressive disorder should be performed. This article is protected by copyright. All rights reserved.

Previous psychiatric disorders in the multistep hypothesis of amyotrophic lateral sclerosis: a South Korean population study

Objective: There is accumulating evidence about an association between amyotrophic lateral sclerosis (ALS) and psychiatric disorders. We aimed to investigate the prevalence of previous psychiatric disorders before ALS onset and evaluate the contribution of psychiatric disorders to the number of steps toward developing ALS.Methods: We analyzed the National Health Insurance claims data from 2011 to 2017 and calculated the incidence of ALS. We created a multistep model using the linear least squares method with regression of the log incidence against the log age.Results: The mean annual incidence of ALS was 0.95/100,000 and frequency of familial ALS (fALS) was 5.89%. The proportions of patients who had psychiatric disorders before ALS diagnosis were 36.8% and 47.0% in fALS and sporadic ALS (sALS), respectively (p = 0.009). In both fALS and sALS, depressive disorders and anxiety and stress disorders were relatively frequent, whereas psychotic disorders and bipolar disorders were rare. Further, the slope estimates for regression analyses were 3.50 (R² = 0.94) and 3.56 (R² = 0.99) for fALS and sALS, respectively, suggesting a 4-5-step process to ALS onset. However, slope estimates did not differ between sALS patients with pre-symptomatic psychiatric disorders and those without.Conclusions: The incidence of ALS is relatively low in Korea and fewer steps are required to develop ALS compared to Western populations (all 6 steps). Although the prevalence of previous depression or anxiety is seemingly high, the multistep model provides no evidence that these conditions modify the risk of developing ALS in our cohort.

Thromboembolic complications following intravenous immunoglobulin therapy in immune-mediated neurological disorders

BACKGROUND

Minor adverse events of intravenous immunoglobulin (IVIg) include flu-like symptoms, eczematous skin reaction, electrolyte disturbance, and transient leukopenia. On rare occasions, serious complications such as aseptic meningitis, arrhythmia, decrease in blood pressure, and thromboembolic complications (TEC) have been described. The current study aimed to understand the frequency and clinical features of TEC related to IVIg administration in patients with immune-mediated neurological disorders.

METHODS

We conducted a retrospective chart review of hospitalized patients with immune-mediated neuromuscular or neuroimmunological disorders treated with IVIg from January 2018 to March 2020 in a single tertiary hospital.

RESULTS

During the study period, 61 patients were treated with a total of 364 IVIg infusions over 84 treatment courses. Among them, we identified 3 TEC cases that occurred during or after the completion of IVIg therapy: two patients with myasthenia gravis (F/60 and F/80) and one patient with Guillain-Barré syndrome (F/79) had undergone arterial TEC (two for ischemic stroke and one for pulmonary thromboembolism). The rates of TEC per patient, per treatment course, and per infusion were 4.91% (3/61), 3.57% (3/84), and 0.82% (3/364), respectively.

CONCLUSION

The risk of developing TEC upon receiving IVIg infusions is generally low in patients with immune-mediated neurological disorders; however, IVIg-related TEC should be cautiously monitored for in critically ill elderly patients with vascular risk factors, especially those suffering from myasthenic crisis.

The seasonal pattern of restless legs syndrome in a sample from the Korean Health Insurance Review and Assessment Service national database

STUDY OBJECTIVES

To assess the seasonality of restless legs syndrome (RLS) using data from the Korean national health insurance database.

METHODS

We retrospectively reviewed a randomly selected sample representing 3% of the national health insurance claims database in South Korea. From this sample, we obtained the monthly numbers of patients with RLS and diagnoses from 2009 to 2016, along with prescriptions for monthly dopamine agonists and clonazepam for patients with RLS from 2009 to 2013. Total dopamine agonist and clonazepam doses were converted to levodopa-equivalent doses, and the monthly cumulative prescription dose was calculated. Cosinor analysis was used to evaluate the seasonal pattern of each variable.

RESULTS

This study included 11,466 patients with RLS and their diagnoses and 4,887 prescriptions for dopamine agonists and clonazepam. There were significant seasonal patterns in the numbers of patients with RLS (P < .001) and diagnoses (P < .001), both of which peaked in August. The magnitude of the greatest difference in the number of patients with RLS between August (highest) and February (lowest) was 29.96% (95% confidence interval, 24.03-100.80), and that of the number of RLS diagnoses was 39.56% (95% confidence interval, 31.24-47.89). The cumulative prescription dose of medication showed no significant seasonality.

CONCLUSIONS

Our findings suggest that the prevalence of RLS is seasonally affected, with an increase during summer.

Radiomics-based model for predicting pathological complete response to neoadjuvant chemotherapy in muscle-invasive bladder cancer

AIM

To develop and validate a radiomics-based model for predicting response to neoadjuvant chemotherapy (NAC) using baseline computed tomography (CT) images in patients with muscle-invasive bladder cancer (MIBC).

MATERIALS AND METHODS

A radiomics signature for predicting pathological complete response (pCR) was developed using radiomics features selected by a random forest classifier on baseline CT images, and imaging predictors were identified in the training set (87 patients). By incorporating imaging predictors and radiomics signature, an imaging-based model was constructed using multivariate logistic regression analysis and validated in an independent validation set consisting of 48 patients with CT from outside institutions. The performance and clinical usefulness of the imaging-based model for predicting pCR were evaluated using area under the receiver operating characteristic curve (AUC) and decision curve analysis. Using a cut-off determined in the training set, the positive likelihood ratios of the imaging-based model were calculated and compared with imaging and histological predictors.

RESULTS

The radiomics signature was developed based on six stable radiomics features. An imaging-based model incorporating radiomics signature, tumour shape, tumour size, and clinical stage showed good performance for predicting pCR in both the training (AUC, 0.85; 95% confidence interval [CI], 0.78-0.93) and validation (AUC, 0.75; 95% CI, 0.60-0.86) sets, providing a larger net benefit in decision curve analysis. The imaging-based model showed a higher positive likelihood ratio (1.91) for pCR than imaging and histological predictors (1.33-1.63).

CONCLUSIONS

The radiomics-based model using baseline CT images may predict the response of patients with MIBC to NAC.

Risk factors for developing post-thymectomy myasthenia gravis in patients with thymoma

BACKGROUND

Thymectomy is required for the treatment of thymoma-associated myasthenia gravis (MG). However, MG may develop only after thymectomy, a condition known as post-thymectomy MG. This study aimed to investigate the risk factors for post-thymectomy MG in patients with thymoma.

METHODS

We retrospectively identified 235 patients with thymoma who underwent thymectomy at a single hospital from January 2008 to December 2017: 44 with preoperatively diagnosed MG were excluded, leaving 191 patients in the final analysis. Univariable survival analyses using Cox proportional hazards regression model and Kaplan-Meier estimate were conducted to identify risk factors for post-thymectomy MG.

RESULTS

Post-thymectomy MG developed in 4.2% (8/191) of the patients with thymoma between 18 days and 108 mo after surgery. Hazard ratios (HRs) of pre- and postoperative anti-acetylcholine receptor antibody (AChR-Ab) titers were 2.267 (P = .002) and 1.506 (P < .001), respectively. Patients with extended thymectomy had a low chance of post-thymectomy MG (HR 0.035, P = .007). Larger thymoma (HR, 1.359; P = .005) and type A or AB thymoma according to World Health Organization histological classification (HR, 11.92; P = .021) were associated with higher chances of post-thymectomy MG. Within the subgroup of preoperatively AChR-Ab seropositive patients, post-thymectomy MG developed in 22.2% (6/27).

CONCLUSIONS

Pre- and postoperative AChR-Ab levels should be measured in patients with thymoma. A large thymoma and partial thymectomy appear to be associated with a higher probability of post-thymectomy MG.

HyperCKemia in Guillain-Barré Syndrome

The aim of the present study was to investigate the frequency and clinical features of Guillain-Barré syndrome (GBS) with hyperCKemia. We retrospectively identified 139 patients with GBS at 2 teaching hospitals in South Korea. We excluded patients with Miller-Fisher syndrome (n = 19), acute bulbar palsy (n = 3), and those whose serum creatine kinase (CK) levels were not measured (n = 45). Twelve of 72 patients (16.7%) had transient hyperCKemia, defined as serum CK ≥300 IU/L. The frequency of male sex and non-demyelinating electrodiagnostic features were higher in patients with hyperCKemia than those without. Transient hyperCKemia, occasionally seen in patients with GBS may be associated with the non-demyelinating subtype.