Safety, efficacy and steroid-sparing effect of amifampridine in Lambert-Eaton myasthenic syndrome patients - real world data.

INTRODUCTION: Lambert-Eaton myasthenic syndrome (LEMS) is an ultrarare neuromuscular disease with a triad of symptoms: muscle paresis, dysautonomy, and areflexia. Amifampridine is the symptomatic treatment of LEMS. AIM OF STUDY: To assess the effectiveness and safety of treatment in the real world. MATERIAL AND METHODS: 14 patients with non-neoplastic LEMS treated with amifampridine were enrolled in the study (female 42.9%, mean age 48.8 ± 11.4 years). The patients were assessed using the Quantitative Myasthenia Gravis (QMG) scale, QMG limb domain (LD) score, spirometry, Hand Grip Strength (GRIP) test, and repetitive nerve stimulation study (RNS) at baseline and at the end of follow-up. Diagnostic delay since first symptoms was from seven months up to 22 years. Treatment delay ranged from one to 26 years. The patients were treated and reevaluated after 21.1 ± 12.0 weeks (range 13-48). RESULTS: All of the patients improved in QMG score. Mean improvement was 5.1 ± 2.0 (range 1-8) points (p < 0.001) and this showed no correlation with the duration of the disease before treatment (p = 0.477). 85.7% of patients (N = 12) improved ≥ 3 points (clinically meaningful) in QMG. 78.6% of the patients improved in QMG LD (mean 2.2 ± 1.6 points (p < 0.001)). Also, forced vital capacity (FVC) improved after treatment (p = 0.031). Mean improvement in GRIP test was 7.0 ± 7.1 kg in the right hand and 5.2 ± 7.5 kg in the left hand (p < 0.001). In RNS before treatment, facilitation ( > 100%) was observed in 78.6% (N = 11) of patients, and was higher before treatment (p < 0.001). Compound muscle action potential (CMAP) amplitude was higher after treatment (p < 0.001). Mean increase of CMAP amplitude was 2.1 ± 1.6 times. In 64.3% (N = 9) of patients lowering of corticosteroid dose was achieved. CONCLUSIONS: Amifampridine is an effective treatment in non-neoplastic LEMS patients, regardless of disease duration. The treatment is well-tolerated and allows to reduce dose of corticosteroids in the majority of patients.

Myasthenia gravis-treatment and severity in nationwide cohort.

INTRODUCTION: Myasthenia gravis (MG) is a rare autoimmune disorder of neuromuscular junction. MG healthcare burden has not been studied in Poland before. METHODS: Data were drawn from the National Health Fund database; MG patient was defined as a person who received at least once medical service with ICD-10 code MG (G70) and at least two reimbursed prescriptions for pyridostigmine bromide or ambenonium chloride in two consecutive years. We have analyzed treatment: immunosuppression, intravenous immunoglobulins (IVIg), plasma exchange (PE), the number and length of hospitalizations (LOS), intensive care unit (ICU) care, and deaths between 2013 and 2018. RESULTS: In 2018, there were 9012 MG patients (F:M 1.62:1), and 30.6% had early -onset MG (<50 years). 66.3% received symptomatic treatment only, 33.7%-glucocorticoids (CS) and/or other immunosuppressants (IS), 64.6%-CS only, 17.5%-azathioprine plus CS, 11%-azathioprine only, 4.6%-CS plus other IS (methotrexate, mycophenolate mofetil, cyclosporine, or tacrolimus), and 2%-other IS only. In 2018, 42.3% of patients were hospitalized at least once (mean 2.05/year), 13.7% due to MG (1.47/year). In 2018, 1.63% patients received PE, 2.33% IVIg. In 2013-2018, 2.7%-3.2% of MG patients required hospitalization in ICU. ICU mean LOS 2013-2018 was 11.5-15.0 days/per patient/year. 2.1% of all MG patients had myasthenic crisis. Mean age at death was 75.7 years for MG and 73.9 for general population (p = .006). All-cause mortality was higher for men (4.1%-5.1%) than for women (2.5%-3.1%), p < .01. CONCLUSIONS: Our findings confirm significant healthcare burden of MG, comprising a tool to plan resources needed for MG patients.

Myasthenia Gravis in Poland: National Healthcare Database Epidemiological Study.

INTRODUCTION: Myasthenia gravis (MG) is a rare autoimmune disorder of the neuromuscular junction. MG epidemiology has not been studied in Poland in a nationwide study before. METHODS: Our epidemiological data were drawn from the National Health Fund (Narodowy Fundusz Zdrowia, NFZ) database; an MG patient was defined as a person who received at least once medical service coded in ICD-10 as MG (G70) and at least 2 reimbursed prescriptions for pyridostigmine bromide (Mestinon®) or ambenonium chloride (Mytelase®) in 2 consecutive years. RESULTS: On 1st of January 2019, 8,702 patients with MG were receiving symptomatic treatment (female:male ratio: 1.65:1). MG incidence was 2.36/100,000. The mean age of incident cases in 2018 was 61.37 years, 59.17 years for women and 64.12 years for men. Incidence of early-onset MG (<50 years) was 0.80/100,000 and 4.98/100,000 for late-onset MG (LOMG), with male predominance in LOMG. Prevalence was 22.65/100,000. In women, there was a constant increase in prevalence of symptomatic MG from the first decade of life up to 80-89 years. In men, an increase in prevalence appeared in the 6th decade. The highest prevalence was observed in the age group of 80-89 years: 59.65/100,000 in women and 96.25/100,000 in men. CONCLUSIONS: Our findings provide information on epidemiology of MG in Poland and can serve as a tool to evaluate healthcare resources needed for MG patients.

Serum interleukin 15 levels in patients with seropositive myasthenia gravis do not correlate with disease severity.

AIM: To assess interleukin 15 (IL-15) serum levels in patients with seropositive myasthenia gravis (MG); searching for potential relationship between IL-15 levels and clinical features such as gender, age at onset, clinical presentation or treatment received. BACKGROUND: IL-15 plays pivotal role in T-cell dependent autoimmunity. Increased IL-15 serum levels have been reported in several autoimmune diseases including MG patients from Japan. PATIENTS AND METHODS: Sera of 42 seropositive MG patients (66.7% women), mean age 50.6±23.7 years) have been tested by ELISA for IL-15 levels. RESULTS: There were no statistically significant differences between IL-15 serum levels in MG patients in comparison with controls as well as between subgroups of MG patients (early vs. late onset and thymoma MG). Mean/median IL-15 serum levels were similar in MG patients treated with corticosteroids (CS) and CS naïve. Outliers (very high values) were seen only in untreated generalized MG patients. CONCLUSIONS: Serum interleukin 15 levels in patients with seropositive myasthenia gravis do not correlate with disease severity.

Lower BAFF Levels in Myasthenic Patients Treated with Glucocorticoids.

B-cell activating factor (BAFF), a member of tumor necrosis factor family, activates B cells, promotes their survival and proliferation. BAFF is considered to have an influence on development of autoimmune diseases including myasthenia gravis (MG). We aimed to evaluate BAFF serum levels in MG patients, their potential connection with therapy and course of MG. Cross-sectional study. Two hundred eighteen adult patients with MG (67% women, age: 18-89 years, 82.6% AChR antibody seropositive (AChRAb(+)). Serum BAFF levels, their relationship with severity of clinical symptoms, therapy conducted, clinical and demographic features and other factors were analyzed. Patients with AChRAb(+) MG demonstrated significantly higher BAFF levels than MuSK-MG patients (831.2 ± 285.4 pg/ml vs. 745.6 ± 633.4 pg/ml, respectively; p = 0.030). Serum BAFF levels in women were significantly higher than in men (855.9 ± 302.5 vs. 756.6 ± 289.4, respectively; p = 0.017). Mean serum BAFF level was significantly decreased in patients who were ever treated with corticosteroids (CS) (770.4 ± 327.8 pg/ml vs. 891.3 ± 246.1 pg/ml, respectively; p = 0.001). Thymoma-MG patients demonstrated significantly lower BAFF levels (671.2 ± 244.9 vs. 833.5 ± 302.4, respectively; p = 0.044). Thymectomized patients did not differ in BAFF levels from the MG patients who had not undergone thymectomy. In multiple linear regression model, recent CS therapy and male sex were found to be independent predictors of lower BAFF levels. Serum BAFF level is decreased in patients treated with CS, which may suggest inhibiting influence of CS on BAFF-a potential mechanism contributing to the effectiveness of such therapy.

Determinants of Quality of Life in Myasthenia Gravis Patients.

Background: Although approximately half of myasthenia gravis (MG) patents achieve remission, for the remaining group MG is often a life-long disease. Better understanding of the determinants of Quality of Life (QoL) in MG is needed to optimize treatment goals in chronic cases. Materials and Methods: We performed a single center cross-sectional study in 339 MG adult patients (64.9% women), with ocular or generalized disease. SF-36 and a structured questionnaire was administered, including information on previous and current MG severity, medications, comorbidities, education, occupation and BMI of the patient. Mean disease duration was 7.5 + 9.3 years. Current age was 51.6 + 18.3 years, 55% had Early-Onset (<50 years) MG. Results: There were no statistically significant differences in mean SF-36 subscores between women and men. Worse MGFA class was related to lower QoL in physical (PCS) and mental (MCS) subscore (p = 0.000 for both). Patients with MGFA I-II class had significantly better QoL in physical and mental subscores than patients with more severe MG (p < 0.005). Late-onset MG patients had worse QoL than EOMG in physical score domain PCS (p = 0.049). Overweight and obese patients had lower PCS (p = 0.002) and MCS (p = 0.038) than patients with normal BMI. University education was related to statistically higher PCS (p = 0.015) and MCS (p = 0.006). QoL in currently employed was better in PCS and MCS (p = 0.000), with white collar workers reporting higher PCS (p = 0.049) than the remaining group. Patients living with family evaluated their MCS (p = 0.015) better than living alone. Moderate physical activity (twice a week) improved PCS (p = 0.045). Conclusion: Our study confirmed that greater severity of symptoms, age, age of onset but also BMI, type of work, education status and physical activity affect QoL in MG.