US claims study links generalized myasthenia gravis exacerbations to higher healthcare use and costs

A 2026 retrospective claims study found that nearly half of 6,195 adults in the United States with newly diagnosed generalized myasthenia gravis experienced an exacerbation or myasthenic crisis during an average follow-up of 33.4 months. Among patients with at least 12 months of follow-up after a clinical event, mean annual healthcare costs were $95,821, compared with $25,029 among a matched cohort without an event.

The study used administrative medical and pharmacy claims from the Komodo Research Database for January 2017 through September 2023. Adults were included if claims showed a neurologist-confirmed myasthenia gravis diagnosis after at least 12 months of continuous insurance eligibility and if they had at least 12 months of continuous eligibility after diagnosis for follow-up. The database draws from more than 150 payers and represents more than 160 million patients across the United States, including people with commercial, Medicare Advantage and Medicaid coverage.

The analytic cohort had a mean age of 61.1 years, and 49.1% were female. Most participants were White, lived in the South and had commercial insurance. Common physical comorbidities included hypertension, obesity and diabetes. A multivariable Cox proportional hazards model examined associations between baseline characteristics and the first claims-defined exacerbation or crisis while adjusting for the other variables included in the model. Because the claims did not contain standardized severity measures such as MG-Activities of Daily Living scores, baseline symptoms were used as proxies for disease severity.

During follow-up, 3,045 patients had a first clinical event, with a mean time of 5.4 months from the index date to the event. Of these events, 98.2% were classified as myasthenic exacerbations and 1.8% as crises. Baseline factors associated with a higher event hazard included immunoglobulin use (hazard ratio, 1.54), dysarthria (1.45), general or other muscle-specific weakness (1.38), use of non-steroidal immunosuppressants (1.37), dysphagia (1.28), weight loss (1.27), dyspnea (1.23) and ptosis (1.20). Absence of another neurological condition was associated with a hazard ratio of 1.20, absence of another autoimmune disorder with 1.18, and male sex with 1.15. All of these associations had p-values below 0.05 and do not establish causation.

For the burden analysis, the researchers formed a clinical-event cohort of 2,657 patients and a no-event cohort of 3,092 patients, each with at least 12 months of follow-up after its index date. The index date was the first event for the clinical-event cohort and a random date with a medical visit for the no-event cohort. Entropy balancing reweighted the no-event group on age, sex, race and ethnicity, geographic region, payer, index year, time since initial myasthenia gravis evidence and baseline diagnosis.

After balancing, patients with an event had 6.02 times the rate of all-cause inpatient admissions, 1.91 times the rate of emergency-department visits and 1.58 times the rate of outpatient visits during the 12 months after indexing; all reported p-values were below 0.05. They also had 5.82 times as many inpatient days: 9.01 days compared with 1.55. For myasthenia gravis-related utilization, the corresponding rate ratios were 16.09 for inpatient admissions, 12.23 for emergency-department visits and 3.96 for outpatient visits.

Mean all-cause total healthcare costs per patient per year were $95,821 in the clinical-event cohort and $25,029 in the no-event cohort, a mean difference of $70,792 (p<0.001). Pharmacy and medical costs each accounted for roughly half of that difference. The $18,103 difference in immunoglobulin costs represented 51.3% of the pharmacy-cost gap. Inpatient costs contributed $25,271, or 71.1%, of the medical-cost difference. Mean myasthenia gravis-related annual costs were $73,641 with an event and $6,469 without one, a difference of $67,172 (p<0.001). Monthly all-cause costs among event patients rose from $5,786 before the event to $19,325 in the following month and remained between $6,626 and $7,268 in subsequent months.

The findings support the value of early risk stratification but remain observational. The claims algorithm may have included some patients with ocular rather than generalized disease because the relevant diagnostic codes do not distinguish those forms. Exacerbations and crises could also have been misclassified, and the analysis did not exclude encounters involving concurrent conditions such as infection. Standardized clinical severity measures and unmeasured factors such as socioeconomic status were unavailable. The study period overlapped the COVID-19 pandemic, and results may not apply to uninsured people or those covered by payer types outside the database. Consequently, the study identifies associations and resource use, rather than demonstrating that any treatment or clinical action prevents events.

Subject of Research: Clinical-event predictors and healthcare costs associated with generalized myasthenia gravis in the United States

Article Title: Exacerbations and crises in generalized myasthenia gravis: predictors and associated economic burden in the United States

Article References: Grover, K., Cloutier, M., Coteur, G., Boonmak, P., El Khoury, A. C., Zhdanava, M., Tardif-Samson, A., Wang, Y., & Gandhi, K. (2026). Exacerbations and crises in generalized myasthenia gravis: predictors and associated economic burden in the United States. Frontiers in Neurology, 17, Article 1919726. https://doi.org/10.3389/fneur.2026.1919726

Image Credits: AI Generated

DOI: 10.3389/fneur.2026.1919726

Keywords: generalized myasthenia gravis, myasthenic exacerbation, myasthenic crisis, healthcare resource use, healthcare costs, claims analysis, United States, Exacerbations, crises, generalized, myasthenia, gravis