Predictors of Outcome in Myasthenic Crisis.

Introduction/aims: The impact of maintenance steroid sparing immunosuppression (SSIS) and prednisone dosage on myasthenic crisis (MC) outcomes and their effects on the development of sepsis have not been well described. This study aimed to investigate the predictive value of these variables on MC outcomes.

Methods: This retrospective, multi-center study examined the potential predictors of MC outcomes using univariate and multivariate analyses through mixed-effect logistic regression and Cox proportional hazards regression.

Results: We included 57 MCs that occurred in 52 patients with a median age of 55 years (interquartile range [IQR]: 33-66), 26 of whom (45.6%) were male. Multivariate analysis showed that sepsis was associated with prolonged length of intensive care unit (ICU) stay (hazard ratio [HR] for time to discharge from the ICU: 0.27, 95% confidence interval [CI]: 0.11-0.71) and duration of ventilation (HR for time to extubation: 0.28, 95% CI: 0.12-0.67). Predictors of sepsis development were age > 50 years (odds ratio [OR]: 7.74, 95% CI: 1.29-46.53) and prednisone use of ≥ 60 mg/day during ICU stay (OR: 13.07, 95% CI: 2.17-86.73). The presence of maintenance SSIS at MC onset predicted a shorter length of ICU stay (HR for time to discharge from the ICU: 2.23, 95% CI: 1.13-4.42) and duration of ventilation (HR for time to extubation: 2.73, 95% CI: 1.37-5.43).

Discussion: The presence of maintenance SSIS at MC onset and the prevention of sepsis are measures that could improve MC outcomes. The use of lower doses (< 60 mg/day) of prednisone, when feasible, could mitigate the risk of sepsis in MC.