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The following is a summary of “Epidemiologic Study of Myasthenia Gravis in the Elderly US Population: A Longitudinal Analysis of the Medicare Claims Database, 2006–2019,” published in the November 2024 issue of Neurology by Bruckman et al.    

Epidemiologic studies indicate an increasing incidence and prevalence among elderly individuals with myasthenia gravis (MG), particularly outside the United States.  

Researchers conducted a retrospective study to estimate how often MG occurs and how many elderly patients with Medicare Fee-For-Service (FFS) live with this condition.  

They analyzed Medicare claims data (2006–2019), and the study participants were aged 65 years and older, had at least 1 month of FFS Part A/B coverage, and lacked health maintenance organization (HMO) insurance coverage. Eligible beneficiaries were grouped into 2-year periods (2006–2007 through 2018–2019), and MG cases were identified based on a validated algorithm using 2 MG claims within each period, either from 2 outpatient visits or a combination of 1 inpatient admission and 1 outpatient visit separated by ≥ 28 days.  

The results showed that the period prevalence of MG increased from 81 to 119 per 100,000 FFS Part A/B beneficiaries (2006–2007 to 2018–2019) (P<0.001). They observed an increase in prevalence across all sex (male/female), ages (65–69/70–74/75–79/80+), race/ethnicity (African American/Asian/Hispanics of any race/non-Hispanic White/other), and census region (Northeast/Midwest/South/West) subgroups. The incidence of MG rose from 12.2 to 13.3 per 100,000 at-risk beneficiary person-years (PYs) from 2008–2009 to 2018–2019 (P<0.05). Increasing incidence trends were significant in men and women, all age groups except 75–79 years, White non-Hispanic individuals, and residents in the Northeast, Midwest, and South regions. All-cause mortality among beneficiaries of MG remained stable, with 6.26 deaths per 100 PYs in 2006–2007 and 5.67 in 2018–2019 (P=0.18).  

They concluded an increased trend in MG prevalence and incidence among elderly individuals in the United States, with variations in rates across specific subgroups over the 14-year study period.  

Source: neurology.org/doi/10.1212/WNL.0000000000210005