Myasthenia Gravis Linked to Greater Longevity Than Multiple Sclerosis

Individuals with myasthenia gravis (MG) lived 15 to 19 years longer than those with multiple sclerosis (MS), across 4 datasets. Individuals with MG show a higher mean age at death than the general population, while those with MS show a significantly lower age at death compared with the general population. While MS is known to shorten life expectancy, less is understood about long-term survival in MG.

A 2026 study published in Therapeutic Advances in Neurological Disorders compared age at death for both conditions with the US population from 2000 to 2015. The authors examined age-at-death patterns during a period preceding today's high-efficacy therapies for both conditions.¹

MG and MS Death Certificate Data Analysis

A retrospective analysis was conducted using mortality data obtained from the State Vital Records Offices in Florida (FL), Wisconsin (WI), Texas (TX), and New York (NY), focused on patients with MG or MS identified from death certificates dated 2000, 2005, 2010, and 2013 or 2015. Life expectancy estimates for the general population for these years were obtained from the US Social Security life tables. Each state contributed data in a different format, requiring customized statistical approaches. These reference values were used to compare mean age at death in the study cohorts with expected life expectancy for the general population.

During the study period, several disease-modifying therapies for MS, including natalizumab and S1P receptor modulators, were available and are known to slow disease progression and reduce relapse rates. However, high-efficacy monoclonal antibodies such as ocrelizumab were not approved until 2017. For MG, immunosuppressive therapies were used, but no novel treatments, including complement inhibitors or FcRn blockers, had been approved, with the last FDA-approved drug for MG dating back over 40 years.

According to a 2022 article from Rare Disease Advisor, roughly 40% of people with MG reach complete remission, though that remission isn't always permanent, as some patients see their symptoms return after a symptom-free period. The article also noted that among MG patients who also have thyroid hyperplasia, 38% to 60% achieve complete, stable remission after thymectomy, an outcome linked to both longer life expectancy and better quality of life.²

Life Expectancy Results: MG vs MS

Using WI and FL death certificates, patients with MS had a shorter age at death than the general population, dying on average 12.4 years earlier than expected (P < .001). In contrast, patients with MG had a higher mean age at death than the general population, living on average 4.8 years longer than expected (P < .0001). Across datasets, MG was associated with a notably older age at death, with adjusted differences of roughly 15 to 17 years in WI and FL and 18 to 19 years in NY, as well as individuals 75 years and older in TX (adjusted odds ratio, 15.71). Even though there were differences in data structure and statistical methods, the findings remained consistent.¹

Observational Study Causation

This analysis is observational and cannot establish causation. The authors noted that disease biology, age at diagnosis, and healthcare access patterns may contribute to the observed differences in survival between MG and MS. The findings relied on death certificate extracts, which did not include age at diagnosis, disease duration, severity, treatment exposure, or cause of death, and diagnoses could not be independently verified. Important demographic and clinical variables, including race, socioeconomic status, comorbidity profiles, MS subtype, and MG serological status, were also unavailable.

The authors noted that survivorship bias is possible, since only individuals who had died were included in the dataset, and that the MG cohort was substantially smaller than the MS cohort. Additionally, the data are also limited to 4 states and the years 2000 to 2015, which the authors note may not be generalizable to the broader US population.

MG and MS Survival Differences

MS was linked to earlier death compared with the general population, whereas MG was linked to a higher mean age at death than both MS and the general population, which is a pattern that was consistent across all 4 states. As the analysis relies heavily on age at death, without detailed clinical data, these findings warrant cautious interpretation. Still, they point to underrecognized MG outcomes and suggest its survival results may differ from what is usually assumed for chronic autoimmune neurological disease.

References

1. Khatri BO, Schutten S, Tarima S. Unexpected longevity in myasthenia gravis: a multi-state population-based comparison with multiple sclerosis and the U.S. population. Ther Adv Neurol Disord. 2026;19:17562864261472638. doi:10.1177/17562864261472638
2. Lopez MA. "Myasthenia Gravis Life Expectancy." Rare Disease Advisor. Reviewed by Kyle Habet, MD, February 25, 2022. https://www.rarediseaseadvisor.com/hcp-resource/myasthenia-gravis-life-expectancy/