1-Year Clinical Outcome Post-Myasthenic Crisis: A Multicenter Prospective Study in China

Myasthenic crisis (MC) affects 10%-20% of myasthenia gravis patients and is life-threatening with significant economic burden, yet its long-term outcomes remain poorly understood. This prospective multicentre study aimed to evaluate 1-year clinical outcomes after MC.

This study enrolled patients with MC between December 2018 and October 2024 and prospectively followed at 1, 2, 3, 6, and 12 months post-MC. Outcome measures included Myasthenia Gravis Foundation of America (MGFA) postintervention status (PIS) classification at 1 year after MC, all-cause mortality, and complications.

The cohort comprised 277 patients with 282 MC episodes with a follow-up duration of 29.16 ± 15.93 months. The in-hospital mortality was 5.05% (14/277), while the all-cause mortality was 15.16% (42/277). The leading causes of death were septic shock (35.7%) and multiple organ failure (21.4%). Among 247 patients with complete 1-year follow-up, 79.76% (197/247) achieved favorable outcomes. MG-ADL scores reduced from 21.3 ± 2.1 at baseline to 5.5 ± 1.5 at 6 months, and 2.8 ± 1.1 at 1 year post-MC (p < 0.01). Multivariable analysis identified older age at crisis (OR 1.03, p = 0.003), thymoma comorbidity (OR 1.84, p = 0.041), higher comorbidity burden (Charlson Comorbidity Index ≥ 3, OR 2.68, p = 0.003), and prolonged ICU stay (OR 1.03, p = 0.002) as independent predictors for minimal symptom expression non-responders. The most frequent chronic complications included infections (15.2%; predominantly fungal pathogens), gastrointestinal disorders (8.3%), and osteoporosis/fractures (5.1%).

This is the first prospective cohort study to report clinical outcomes in MG patients at post-MC stage, highlighting the importance of disease monitoring and early intervention to improve patient-centred care.