By Dr. Emily Cheung, PYNEH
Introduction: Myasthenia gravis (MG) is the commonest neuromuscularjunction disorderthat requires intensive care. Mortality rate has decreased with the improvement in respiratory care in specialized intensive care unit (ICU). However, limited studies have been done on the predictive factors for ICU admission in MG patients.
Objective: The primary objective of this study is to identifythe predictive factors for ICU admission in a local regional hospital. Secondary objectives included identity risk factors for MG related mortality, evaluate the characteristic of MG patients admitted to ICU and identify therisk factors for extubation failure.
Methods and Main results: This is a retrospective single center cohort study carried out in a local tertiary hospital between January 1997 and June 2013. All MG patients diagnosed either in-patient or out-patient by our neurology team during this period was included. Patients’ demographics, MG diseases characteristics and treatment modalities and ICU clinical informations were collected. A total of 164 patients diagnosed to have MG during this period were included in the analysis. MG related mortality rate was 6.1%. Among the study group, 21 patients (12.8%) required ICU admission. The median ICU length of stay was 7 days (2-26). In multivariate logistic regression analysis, presence of axial symptoms on initial MG presentation was found to be the only independent predictive factors for ICU admission (OR 9.67, 95% CI 2.18-42.79, p = 0.003). Moreover, positivity in repetitive stimulation test (RST) was significantly associated with MG related mortality (OR 11.23, 95% CI 1.34-94.1, p = 0.026).
Conclusion: This study found that presence of axial symptoms on initial presentation was the only independent predictive factor for ICU admission and positivity in RST was associated with MG related mortality. Early recognition of high risk patients for potential ICU care is critical to improve the clinical outcome.