Healthcare resource use in myasthenia gravis: a US health claims analysis

Racial disparities in acute care utilization among individuals with myasthenia gravis

Objective

In myasthenia gravis (MG), evidence on the impact of social determinants of health on disparities in disease burden and healthcare resource utilization is limited. This study aimed to investigate the independent association between race/ethnicity and acute care utilization during the 2 years post-diagnosis among patients with MG.

Methods

A retrospective cohort study was conducted among adults (≥18 years) with newly diagnosed MG in the United States using Optum's de-identified Market Clarity Data from January 1, 2010, to December 31, 2019. Multivariable regression models were used to assess the association between acute care utilization and race/ethnicity, insurance, exacerbation at index, and other covariates.

Results

A total of 7,058 patients met the study inclusion criteria, of whom 57% (n = 4,052) identified as Caucasian, 6% (n = 445) African American, 3% (n = 235) Hispanic, 1% (n = 94) Asian, and 32% (n = 2,232) with missing race/ethnicity information. Compared with patients identifying as Caucasian, those identifying as African American had 37% higher odds of having an emergency department visit in year 1, and those identifying as Hispanic had 70% increase in odds of having a hospitalization event in year 2 post-diagnosis. Among other covariates, Medicaid usage, exacerbation at index, and number of outpatient visits were significantly associated with acute care utilization.

Conclusion

Racial disparities significantly impacted acute care utilization in the first 2 years post-MG diagnosis. Future studies should aim to examine specific factors that may contribute to disparities such as barriers to healthcare access, greater severity of MG symptoms, and poorly controlled disease.

Characteristics and healthcare utilization of patients with myasthenia gravis exacerbation

PURPOSE

This retrospective cohort study describes the characteristics of patients with myasthenia gravis (MG) who developed exacerbations (MG-E) and compares their healthcare utilization (HRU) to patients who did not experience exacerbations (MG-O).

METHOD

De-identified data from patients who had ≥2 MG-related diagnostic code submissions were extracted from the National Veterans Affairs Health Care Network electronic health records between 1999 and 2022. Descriptive statistics, Kaplan-Meier analysis, and per-patient per-year (PPPY) HRU were used to compare the two patient groups.

RESULTS

About 34 % (3603/10,718) of patients with MG developed exacerbations over a median follow-up of 6.8 years. Approximately 52 % of the MG-E cohort had 3 or more exacerbations over the study period, averaging 1.34 (SD 2.50) exacerbations per year. The MG-E cohort had a higher incidence of early-onset MG (7.72 % vs. 4.05 %; p < 0.0001) and higher mean Charlson Comorbidity Index scores before a diagnosis of MG (0.86 vs. 0.59; p < 0.0001). Relative to patients of other racial groups with MG-E, Hispanic and African Americans had higher cumulative incidence of exacerbations over time (p < 0.0001). Additionally, MG-E patients were five times more likely to be intubated compared to MG-O patients (p < 0.0001). Increased PPPY HRU was observed in patients with MG-E compared to patients with MG-O (outpatient visit: 25.05 vs. 14.08; inpatient admission: 0.47 vs. 0.14; ED visit: 0.69 vs. 0.26; ICU stay: 0.08 vs. 0.02, respectively; p < 0.001).

CONCLUSION

Approximately one-third of patients diagnosed with MG experienced exacerbations, with higher incidences seen among Hispanic and African Americans. MG-E was associated with higher HRU and a higher intubation risk.

Persistent symptoms, exacerbations and drug side effects despite treatment in myasthenia gravis

BACKGROUND

Generalized myasthenia gravis (gMG) is characterized by fluctuating muscle weakness. Exacerbation frequency, adverse events (AEs) related to immunosuppressant therapy and healthcare resource utilization (HCRU) are not well understood. Our study aimed to describe long-term clinical outcomes, drug-related AEs and estimated HCRU in gMG patients.

METHODS

This was a retrospective cohort analysis of clinical data from patients with gMG followed-up over eight consecutive years in a Spanish referral unit. Myasthenia Gravis Foundation of America (MGFA) clinical classification, MGFA post-interventional status (MGFA-PIS), Myasthenia Gravis Activities of Daily Living (MG-ADL) score, exacerbations, MG crises, therapies, AEs reported, specialist consultations and emergency room visits were studied biannually. An estimation of HRCU was made based on these data.

RESULTS

Some 220 patients newly diagnosed with gMG were included. Ninety percent were seropositive (84.5% anti-acetylcholine receptor [AChR], 5.9% anti-muscle-specific kinase [MuSK]). Baseline mean MG-ADL score was 5.04 points (SD 3.17), improving to 0.7 points (SD 1.40) after 8 years. Exacerbations were more frequent in years 1-2 (30.1%) but still occurred in years 7-8 (20.2%). Myasthenic crisis frequency remained 1% in years 7-8. Eighty-nine percent achieved MGFA-PIS minimal manifestations or better at 8 years. Fifty-one percent of patients reported at least one AE during the study period, leading to drug withdrawal in approximately 20% of cases. HCRU decreased between years 1-2 to years 7-8 with an estimated cost of MG from 8074.19 € per patient/year to 1679.46 €, respectively.

CONCLUSIONS

There is a group of MG patients that suffers from persistent symptoms and exacerbations (11%-20%) or MG crises, and drug AEs, which may increase disease burden and impact on the healthcare system.

Disease burden, healthcare resource utilisation, and treatment patterns in patients with newly diagnosed myasthenia gravis in England: A retrospective cohort study

BACKGROUND

Myasthenia gravis (MG), a chronic and unpredictable autoimmune disease, is associated with multiple comorbidities and high disease burden.

OBJECTIVE

To assess the disease burden, healthcare resource utilisation (HCRU), and treatment patterns of patients with newly diagnosed MG in England.

METHODS

Data from Clinical Practice Research Datalink GP practices linked to the Hospital Episode Statistics database were used. Eligible patients had ≥1 diagnostic code for MG, with the first MG diagnostic code recorded between 01 January 2010 and 31 December 2019. Non-MG controls were selected if they had no recorded MG diagnosis and ≥12 months of data. Controls were matched for age, sex and GP practice in a maximum ratio of 5:1.

RESULTS

Mean follow-up duration was 2.8 and 3.1 years for the MG and non-MG cohorts, respectively. In the MG cohort, 56% of patients were male, with a mean age of 67 years at baseline. Incidence rates of all comorbidities assessed during follow-up were higher in the MG cohort than in controls. Almost two-thirds of MG patients experienced ≥1 myasthenic exacerbation during follow-up; incidence rates (95% confidence interval) of MG exacerbations and crises were 50.0 (44.7-55.9) and 1.3 (0.8-2.0) per 100 person-years, respectively. Visits to non-neurology specialists and outpatient clinics were the most common instances of HCRU overall, each being more frequent in the MG cohort than for controls. In the first year of follow-up, acetylcholinesterase inhibitors (AChEIs) and corticosteroids were used by 56.0% and 50.2% of MG patients, respectively; the use of AChEIs declined thereafter.

CONCLUSIONS

Despite treatment, there is a high disease burden for patients with newly diagnosed MG in England, with high rates of MG exacerbation and HCRU use. Thus, there is a need for targeted treatments with sustained efficacy and improved safety to adequately manage MG symptoms and reduce MG-related disease burden.

Tracking myasthenia gravis severity over time: Insights from the French health insurance claims database

BACKGROUND AND PURPOSE

Few data are available on the course of myasthenia gravis (MG) regarding disease severity and stability over time in real-world settings. This study used the French National Health Insurance Database (SNDS) to assess markers of disease severity in patients with MG longitudinally.

METHODS

All patients with MG-related claims in the SNDS between 2013 and 2020 were identified. Patients were followed for up to 8 years after the first claim. Intensive care unit (ICU) stays, treatment with intravenous immunoglobulin (IVIg) or plasma exchange (PE), and death were documented throughout the follow-up period. Standardized mortality rates were estimated, and mortality-related variables were identified using a Cox model.

RESULTS

In all, 14,459 individuals constituted the full study population, including 6354 incident patients. In the incident population, 2199 (34.6%) were admitted to ICUs at least once, principally during the first year after the index date (N = 1477; 23.3%). This proportion decreased progressively to reach 3.0% in the seventh year. A total of 2817 patients received IVIg and 432 PE, again principally in the first year. In the full study population, the standardized mortality rate was 1.08 (95% confidence interval [CI] 1.03-1.13), being lower in men (0.95, 95% CI 0.89-1.02) than in women (1.15, 95% CI 1.07-1.23) and in patients aged >65 years (1.06, 95% CI 1.01-1.11) than in younger patients (1.50, 95% CI 1.24-1.76). Male gender, older age and higher comorbidity were independently associated with mortality.

CONCLUSIONS

A subgroup of patients with MG require ICU admission and rescue therapy with IVIg or PE, indicative of poor disease control. New therapies are needed to improve disease control and reduce disease burden.

Medical costs of treating myasthenia gravis in patients who need intravenous immunoglobulin (IVIg) - a register-based study

BACKGROUND

Several innovative treatments are expected for myasthenia gravis (MG) in the coming years. Healthcare payers usually require cost-effectiveness analyses before reimbursement. We aimed to investigate resource utilization and direct medical costs for patients with MG treated with intravenous immunoglobulin (IVIg) to inform such analyses.

METHODS

We identified patients with MG in the Norwegian Patient Registry based on at least two hospital encounters with an MG diagnosis (ICD-10 G70.0) from 1 Jan 2010 to 31 Dec 2021. IVIg treatment was identified by medical procedure and Anatomical Therapeutic Chemical (ATC) codes (RPGM05 and J06BA02). Using Diagnosis-Related Group (DRG) cost weights, we estimated direct medical costs for each year following the first MG diagnosis.

RESULTS

Over the study period, 1083 patients were diagnosed with MG in Norway, of whom 155 (14.3%) were treated with IVIg. No significant differences in age or sex were observed between IVIg and non-IVIg patients. Compared with non-IVIg patients, IVIg-patients had 2.3 times higher direct medical costs during the first year after MG diagnosis (EUR 35,714 vs. EUR 15,457) and 3.1 times higher costs during the second year (EUR 19,119 vs. EUR 6256). In the fifth year after diagnosis, IVIg-patients still had higher costs and resource utilization than non-IVIg patients (EUR 9953 vs. EUR 5634).

CONCLUSION

IVIg treatment represents an important marker for high direct medical costs among patients with MG. The costs continue to be high during the first five years after MG diagnosis.

Economic and societal burden of myasthenia gravis in Denmark, Finland, and Sweden: A population-based registry study

BACKGROUND AND PURPOSE

Health care resource utilization (HCRU) and the economic burden of myasthenia gravis (MG) are significant, but existing studies rarely include comprehensive nationwide data. We examined HCRU and direct and indirect costs associated with MG overall and by disease severity in Denmark, Finland, and Sweden.

METHODS

Data were collected retrospectively from nationwide health and social care registries. All individuals ≥18 years of age with ≥2 International Classification of Diseases diagnoses of MG between 2000 and 2020 were included. HCRU, direct (inpatient and outpatient contacts, medication) and indirect costs (early retirement, sick leave, death), and associated factors were calculated.

RESULTS

The full study cohort comprised 8622 people with MG (pwMG). Mean annual numbers of all-cause secondary health care contacts for pwMG were 3.4 (SD = 8.3), 7.0 (SD = 12.3), and 2.9 (SD = 3.9), with mean annual total costs of €12,185, €9036, and €5997 per person in Denmark, Finland, and Sweden, respectively. Inpatient periods, involving 77%-89% of study participants in the three countries, contributed most to direct costs, whereas the majority of indirect costs resulted from early retirement in Denmark and Finland, and sick leave periods in Sweden. Mean annual total costs were highest with very severe MG (€19,570-€33,495 per person across the three countries). Female sex and comorbidities, such as mental and behavioral disorders and severe infections, were also associated with higher total costs.

CONCLUSIONS

This population-based study shows a high level of HCRU and a significant direct and indirect economic burden of MG across three Nordic countries, especially for severe forms of MG.

Long-Term Healthcare Resource Utilization and Costs among Patients with Myasthenia Gravis: A Swedish Nationwide Population-Based Study

INTRODUCTION

Healthcare costs and societal impact of myasthenia gravis (MG), a potentially life-threatening rare, chronic neuromuscular disease, are sparsely studied. We assessed healthcare resource utilization (HCRU) and associated costs among patients with newly diagnosed (ND) and preexisting (PE) MG in Sweden.

METHODS

This observational, retrospective cohort study used data from four linkable Swedish nationwide population-based registries. Adult MG patients receiving pharmacological treatment for MG and having ≥24-month follow-up during the period January 1, 2010, to December 31, 2017, were included.

RESULTS

A total of 1,275 patients were included in the analysis, of which 554 patients were categorized into the ND MG group and 721 into the PE MG group. Mean (±SD) age was 61.3 (±17.4) years, and 52.3% were female. In the first year post-diagnosis, ND patients had significantly higher utilization of acetylcholinesterase inhibitors (96.0% vs. 83.9%), corticosteroids (59.6% vs. 45.8%), thymectomy (12.1% vs. 0.7%), and plasma exchange (3.8% vs. 0.6%); had higher all-cause (70.9% vs. 35.8%) and MG-related (62.5% vs. 18.4%) hospitalization rates with 11 more hospitalization days (all p < 0.01) and an increased risk of hospitalization (odds ratio [95% CI] = 4.4 [3.43, 5.64]) than PE MG. In year 1 post-diagnosis, ND MG patients incurred EUR 7,302 (p < 0.01) higher total all-cause costs than PE MG, of which 84% were estimated to be MG-related and the majority (86%) were related to inpatient care. These results remained significant also after controlling for baseline demographics and comorbidities (p < 0.01). In year 2 post-diagnosis, the all-cause medical costs decreased by ∼55% for ND MG from year 1 and were comparable with PE MG.

CONCLUSION

In this population-based study, MG patients required significantly more healthcare resources in year 1 post-diagnosis than PE MG primarily due to more pharmacological treatments, thymectomies, and associated hospitalizations. These findings highlight the need to better understand potential factors including disease characteristics associated with increased health resource use and costs and need for more efficacious treatments early in the disease course.

Long-term safety and efficacy of zilucoplan in patients with generalized myasthenia gravis: interim analysis of the RAISE-XT open-label extension study

Background

Generalized myasthenia gravis (gMG) is a chronic, unpredictable disease associated with high treatment and disease burdens, with a need for more effective and well-tolerated treatments.

Objectives

To evaluate the long-term safety, tolerability, and efficacy of zilucoplan in a mild-to-severe, acetylcholine receptor autoantibody-positive (AChR+) gMG population.

Design

Ongoing, multicenter, phase III open-label extension (OLE) study.

Methods

Eligible patients had completed a qualifying randomized, placebo-controlled phase II or phase III zilucoplan study and received daily, self-administered subcutaneous 0.3 mg/kg zilucoplan. The primary endpoint was incidence of treatment-emergent adverse events (TEAEs). Secondary efficacy endpoints included change from baseline in Myasthenia Gravis Activities of Daily Living (MG-ADL) score.

Results

In total, 200 patients enrolled. At the cut-off date (8 September 2022), median (range) exposure to zilucoplan in RAISE-XT was 1.2 (0.11-4.45) years. Mean age at OLE baseline was 53.3 years. A total of 188 (94%) patients experienced a TEAE, with the most common being MG worsening (n = 52, 26%) and COVID-19 (n = 49, 25%). In patients who received zilucoplan 0.3 mg/kg in the parent study, further improvements in MG-ADL score continued through to Week 24 (least squares mean change [95% confidence interval] from double-blind baseline -6.06 [-7.09, -5.03]) and were sustained through to Week 60 (-6.04 [-7.21, -4.87]). In patients who switched from placebo in the parent study, rapid improvements in MG-ADL score were observed at the first week after switching to zilucoplan; further improvements were observed at Week 24, 12 weeks after switching (-6.46 [-8.19, -4.72]), and were sustained through to Week 60 (-6.51 [-8.37, -4.65]). Consistent results were observed in other efficacy endpoints.

Conclusion

Zilucoplan demonstrated a favorable long-term safety profile, good tolerability, and sustained efficacy through to Week 60 with consistent benefits in a broad AChR+ gMG population. Additional long-term data will be available in future analyses.

Trial registration

ClinicalTrials.gov identifier: NCT04225871 (https://clinicaltrials.gov/ct2/show/NCT04225871).

A retrospective observational study on characteristics, treatment patterns, and healthcare resource use of patients with myasthenia gravis in England

Background

There are limited data on the real-world healthcare resource use (HCRU) and management costs of myasthenia gravis (MG) in England.

Objective

This study aims to assess the burden of disease for patients with MG in England.

Design

A retrospective, observational cohort study of adult patients diagnosed with MG, using data from the Hospital Episode Statistics data warehouse.

Methods

Patients with a first-ever recorded diagnosis of MG between 30 June 2015 and 30 June 2020 were followed up until 30 June 2021 or death, whichever occurred first. Post-diagnosis patient characteristics, treatment patterns, HCRU, and costs were described. Costs were evaluated using National Health Service reference costs.

Results

A total of 9087 patients with a median follow-up time of 2.9 years (range, 1.7-4.3 years) were included. The mean age at diagnosis was 66.5 years and 53% of the patients were male. A large proportion of patients (72.8%) were admitted as inpatients during follow-up with a mean number of 1.3 admissions. Patients hospitalized for MG-related complications spent a mean of 9.7 days per patient-year in the hospital. During follow-up, 599 (6.6% of the total cohort) and 163 (1.8%) patients had a record of rescue therapy with intravenous immunoglobulin (IVIg) and plasma exchange (PLEX), respectively. Rituximab was administered to 81 (0.9%) patients and 268 (2.9%) patients underwent thymectomy. In those patients receiving rescue therapy or rituximab, >10% received at least three cycles of the same treatment. The average annual cost of hospital admissions across all patients treated with IVIg, PLEX, and rituximab were £907,072, £689,979, and £146,726, respectively.

Conclusion

A majority of MG patients required hospitalization or accident and emergency attendance, resulting in high HCRU and costs. A subset of patients required rescue therapy (including IVIg and PLEX), rituximab administration, ventilation, or thymectomy.

Healthcare resource utilization, costs and treatment associated with myasthenia gravis exacerbations among patients with myasthenia gravis in the USA: a retrospective analysis of claims data

Aim: There are limited data on the clinical and economic burden of exacerbations in patients with myasthenia gravis (MG). We assessed patient clinical characteristics, treatments and healthcare resource utilization (HCRU) associated with MG exacerbation. Patients & methods: This was a retrospective analysis of adult patients with MG identified by commercial, Medicare or Medicaid insurance claims from the IBM® MarketScan® database. Eligible patients had two or more MG diagnosis codes, without evidence of exacerbation or crisis in the baseline period (12 months prior to index [first eligible MG diagnosis]). Clinical characteristics were evaluated at baseline and 12 weeks before each exacerbation. Number of exacerbations, MG treatments and HCRU costs associated with exacerbation were described during a 2-year follow-up period. Results: Among 9352 prevalent MG patients, 34.4% (n = 3218) experienced ≥1 exacerbation after index: commercial, 53.0% (n = 1706); Medicare, 39.4% (n = 1269); and Medicaid, 7.6% (n = 243). During follow-up, the mean (standard deviation) number of exacerbations per commercial and Medicare patient was 3.7 (7.0) and 2.7 (4.1), respectively. At least two exacerbations were experienced by approximately half of commercial and Medicare patients with ≥1 exacerbation. Mean total MG-related healthcare costs per exacerbation ranged from $26,078 to $51,120, and from $19,903 to $49,967 for commercial and Medicare patients, respectively. AChEI use decreased in patients with multiple exacerbations, while intravenous immunoglobulin use increased with multiple exacerbations. Conclusion: Despite utilization of current treatments for MG, MG exacerbations are associated with a high clinical and economic burden in both commercial and Medicare patients. Additional treatment options and improved disease management may help to reduce exacerbations and disease burden.

Physician- and patient-reported perspectives on myasthenia gravis in Europe: a real-world survey

BACKGROUND

Myasthenia gravis (MG) is a rare, chronic, debilitating, unpredictable, and potentially life-threatening neuromuscular disease. There is a lack of real-world data on disease management that could be used to further understand and address unmet patient needs and burden. We aimed to provide comprehensive real-world insights in the management of MG in five European countries.

METHODS

Data were collected using the Adelphi Real World Disease Specific Programme™ in MG, a point-in-time survey of physicians and their patients with MG in France, Germany, Italy, Spain, and the United Kingdom (UK). Physician- and patient-reported clinical data were collected, including demographics, comorbidities, symptoms, disease history, treatments, healthcare resource utilization (HCRU), and quality of life outcomes.

RESULTS

In total, 144 physicians completed 778 patient record forms from March to July 2020 in the UK, and from June to September 2020 in France, Germany, Italy and Spain. Mean patient age at symptom onset was 47.7 years, with a mean time from symptom onset to diagnosis of 332.4 days (10.97 months). At diagnosis, 65.3% of patients were classified as Myasthenia Gravis Foundation of America Class II or above. Mean number of symptoms reported at diagnosis per patient was five, with ocular myasthenia reported in at least 50% of patients. At time of survey completion, the mean number of symptoms reported per patient was five and ocular myasthenia and ptosis were each still present in more than 50% of patients. Acetylcholinesterase inhibitors were the most commonly prescribed chronic treatments in all countries. Of 657 patients treated with chronic treatment at the time of the survey, 62% continued to experience moderate-to-severe symptoms. On average, 3.1 healthcare professionals (HCPs) were involved in patient management, 6.2 consultations were made per patient with any HCP over the last 12 months, and 178 (22.9%) patients were hospitalized in the last 12 months. Overall, HCRU and disease management were similar across all countries.

CONCLUSIONS

Our findings demonstrated the high burden of MG despite current treatment options for patients with MG.