The Etiology Analysis of Myasthenia Gravis with In-Hospital Mortality in the Neurocritical Care Unit.

Background: Our objective was to investigate the characteristics and causes of death in deceased patients with myasthenia gravis (MG).

Methods: This study conducted a retrospective analysis of data from patients with MG in the neurocritical unit at two large general hospitals in China spanning 10 years, from January 2014 to December 2023. Detailed demographic and clinical information were collected for deceased patients. Experienced physicians determined both the underlying and direct causes of death.

Results: Among 3723 patients, the overall hospitalized mortality was 79 (2.12%). Thymoma was present in 52 (65.82%) of these patients. Compared with the nonthymomatous MG (NTMG) group (n = 27), patients with thymomatous MG (TMG) (n = 52) were significantly younger at death (53.71 ± 14.01 years vs. 65.37 ± 14.61 years, p = 0.001). Septic shock was the most common underlying cause of death, affecting 32 (40.51%) patients, followed by myasthenic crisis in 18 (22.78%) patients. This trend was observed in both the TMG and NTMG groups. In the TMG group, fulminant myocarditis was the third leading underlying cause of death in 9 (17.31%) patients, whereas no cases of fulminant myocarditis were reported in the NTMG group. Among all deceased patients (n = 79), pneumonia was the most common infection, affecting 55 (69.62%) patients, followed by urinary tract infections in 14 (17.72%) patients, bloodstream infections in 13 (16.46%) patients, and intracranial infections in 7 (8.86%) patients.

Conclusions: The study suggests that thymoma may increase the risk of death, with septic shock and myasthenic crisis being the most frequent underlying causes in patients with MG.