To investigate whether there is a significant difference in mortality in adult patients with severe myasthenia gravis, determined by use of a mechanical ventilator,  between intravenous immunoglobulin (IVIg) and steroids.

Steroids and IVIg are both used in the treatment of patients with severe myasthenia gravis.

The New York State Planning and Research Cooperation (SPARCS) database was utilized to collect all adult patients with myasthenia gravis (MG) who were mechanically ventilated. Patient’s age was restricted to 18 or older. Patients taking both IVIg and Steroids were excluded from analysis.

 1,730 patients with MG on mechanical ventilators were collected for analysis. 595 patients died. 63 patients received steroid treatment and 19 of these patients died (30.1%). 154 myasthenia gravis patients received IVIg treatment and 30 of them died (19.4%). There was no significant difference in average age between the two groups (77.13±14.54 vs 72.58±10.34; p=0.241) or gender (p=0.136). There was no significant difference in proportion who received IVIg versus steroid (p=0.116). Multivariate regression analysis performed on all patients demonstrated that the likelihood of death is not significantly different between the use of steroids compared to patients not treated with steroids or IVIg (OR: 1.023; 95% CL: 0.578-1.812; p=0.937). However, the likelihood of death was significantly reduced in the group treated with IVIg compared to the patients who did not receive IVIg or steroids (OR: 0.510; 95% CL: 0.332-0.782; p=0.002).

IVIg was associated with a decreased likelihood of mortality in patients with severe myasthenia gravis when compared to steroids. Limitations of this analysis include differential treatment algorithms for IVIg and steroids, and different situations for their use. Work is ongoing to calculate the likelihood confounding for comorbid conditions, with subgroup analysis and increasing length of time for study period.