Submitted by: Nakul Katyal, MD
Edited by: Rebecca O'Bryan, MD
Citation: Morganroth J, Zuroff L, Guidon AC, et al. Trends and Disparities in the Utilization of Thymectomy for Myasthenia Gravis in the United States. Neurol Clin Pract. 2024;14(5):e200335. doi:10.1212/CPJ.0000000000200335
Summary: Thymectomy has long been a standard treatment for non-thymomatous myasthenia gravis (MG). The Myasthenia Gravis Thymectomy (MGTX) trial demonstrated that patients who underwent thymectomy had lower steroid requirements, reduced need for alternative immunosuppressants, less severe symptoms over time, and fewer hospitalizations due to exacerbations.
This study examined thymectomy usage patterns among non-thymomatous MG patients over 18 years old across the United States (US), utilizing data from the National Inpatient Sample (NIS) from 2012 to 2019. A retrospective longitudinal cross-sectional analysis was conducted, and logistic regression models were used for subgroup analysis to identify patient and hospital-level factors influencing thymectomy utilization.
Between 2012 and 2019, 4,430 thymectomies were performed for non-thymomatous MG in the US. Of these, 2,505 were trans-sternal and 1,925 were minimally invasive. The annual number of thymectomies increased from 45 in 2012 to 1,150 in 2019, with an average annual percent change of 69.8% (95% CI 40.1–105.8). Trans-sternal thymectomies increased by 62.8% per year (95% CI 35.8–95.2), and minimally invasive thymectomies increased by 83.7% per year (95% CI 38.1–144.3). Thymectomies were significantly more likely to occur between 2017 and 2019 compared to 2012–2016 (OR 1.93, 95% CI 1.62–2.31).
Certain factors decreased the likelihood of MG patients undergoing a thymectomy: older age, Black race (OR 0.62, 95% CI 0.49–0.77), female gender (OR 0.73, 95% CI 0.63–0.86), and a higher Elixhauser Comorbidity Index.
Patients treated at medium (OR 1.82, 95% CI 1.30–2.55) or large (OR 2.81, 95% CI 2.07–3.82) hospitals and urban teaching hospitals (OR 6.09, 95% CI 2.65–13.97) were more likely to undergo thymectomy.
Comments: Over time, the number of thymectomies performed for MG in the United States has risen. This increase aligns with the publication of the MGTX trial in 2016, suggesting that the trial may have impacted clinical practice. Significant gender and racial disparities in thymectomy utilization were observed, warranting further investigation.
Article of Similar Interest: Hamedani AG, McPherson TO, Aban I, et al. Attitudes and Beliefs Toward Thymectomy in the Myasthenia Gravis Patient Registry. J Clin Neuromuscul Dis. 2023;24(4):222-228. doi:10.1097/CND.0000000000000449