US study identifies risks for longer hospital stays to treat acute MG
Risk factors include being male, intubation, and plasma exchange therapy
Being male, requiring intubation, and receiving plasma exchange therapy were identified as the main predictors of longer hospital stays following an acute episode of disease worsening in people with myasthenia gravis (MG), according to a recent study.
Data also show that patients who underwent surgery to remove the thymus gland — a procedure called thymectomy — stayed in the hospital for a shorter period of time.
The study, “Analysis of length of stay and treatment emergent complications in hospitalized myasthenia gravis patients with exacerbation,” was published in the journal BMC Neurology.
MG occurs when self-reactive antibodies mistakenly attack proteins that play a key role in nerve-muscle communication. This causes patients to experience muscle weakness, including in the muscles that control breathing.
The condition is usually caused by antibodies targeting a protein called an acetylcholine receptor, but more rarely, it may be driven by antibodies targeting another protein called muscle-specific kinase (MuSK).
Myasthenic exacerbations are episodes in which disease symptoms worsen, requiring patients to be monitored or treated. Moreover, exacerbations are known to contribute to disease burden in patients who fail to respond properly to treatments.
However, there is a lack of data about the health resources used when a patient experiences an acute exacerbation and the subsequent effects on disease outcome.
Study set out to identify factors for prolonged hospitalization in 70 patients
To learn more, a team of researchers in the U.S. carried out a study to identify the factors that might be associated with a prolonged hospital stay in patients with generalized MG following acute exacerbations.
Their study included a total of 70 patients with 141 recorded hospitalizations due to acute exacerbations. All patients were treated at a single hospital between 2010 and 2019.
For each exacerbation, the researchers evaluated several variables, including the patients’ age, sex, and whether or not they underwent a thymectomy. Other variables assessed included treatments received before and after an exacerbation, length of hospital stay, need for intubation, and development of complications.
Patients were 55.8 years old on average at the time they were hospitalized. Vaccine non-preventable infection and medication-related effects were the most common causes for exacerbations where a specific cause could be identified.
Patients remained in the hospital for a mean of 8.58 days (median of six days), with most being hospitalized for less than 25 days.
Data revealed that in every five hospitalizations, one required intubation. A strong relationship was found between increased length of hospital stay and intubation, with patients requiring intubation staying in the hospital much longer than those who did not (mean of 21.64 vs. 5.77 days). Intubation was also found to be the “strongest predictor” of a long hospital stay.
Plasmapheresis, or plasma exchange therapy, also contributed to longer hospital stays. This was expected as “a course of plasmapheresis necessitates a minimum of 10 days in the hospital,” the researchers wrote. Patients receiving plasmapheresis stayed in the hospital for a mean of 13.2 days, while those who did not were hospitalized for a mean of 4.63 days.
Results also showed that patients who had previously undergone a thymectomy stayed in the hospital for shorter periods of time than those who did not have surgery (mean of 5.81 vs. 9.53 days). This “may relate to the role of the thymus in MG pathogenesis [development],” the researchers wrote.
Male patients experienced longer hospital stays than female patients
The study also found that male patients remained in the hospital for a longer period of time compared with female patients (mean of 12.88 vs. 6.63 days).
In more than half (63%) of the recorded hospitalizations, treatment-related complications were reported, the most common being infection.
Of the total hospital admissions, 33% resulted in discharge to a unit specialized in post-exacerbation care, 7% were discharged to receive medical care at home, and one resulted in death.
“With a number of novel immunosuppressive drugs under current investigation for generalized MG therapy, this study may help clarify where the gaps are in acute MG treatment,” the scientists wrote.
“It will be of interest to see if novel therapies have an impact on hospital length of stay for MG exacerbation patients,” they added. “Continued evaluation of the effect of resources employed during exacerbation management on disease outcomes will be important to establish a basis of comparison as novel treatments advance through clinical trials.”