Sleep disorders occur frequently, in multiple brain networks, with autoimmune encephalitis
Autoimmune encephalitis can affect any network of the brain related to sleep and result in various sleep disorders both during and after the acute disease phase, according to a review published in The Lancet Neurology.
“... Sleep disorders in autoimmune encephalitis are usually severe and persist beyond the acute phase of the disease, affecting the process of recovery and quality of life,” Amaia Muñoz-Lopetegi, MD, of the Hospital Clinic and August Pi i Sunyer Biomedical Research Institute at the University of Barcelona, and colleagues wrote.
Muñoz-Lopetegi and colleagues’ review, which noted that “all major types of sleep disorders can occur in autoimmune encephalitis,” described the ways in which these different disorders manifest in the setting of autoimmune encephalitis.
According to Muñoz-Lopetegi and colleagues, video-polysomnography (V-PSG) evaluation is “the gold standard” for performing a physiological assessment and behavioral observation of sleep. In addition, while sleep-related symptoms “are rarely the main reason” that patients with autoimmune encephalitis see a clinician, these symptoms are easily identified when patients are asked.
“Although treatment needs vary based on the specific sleep disorder experienced, early recognition and diagnosis of sleep disturbances in patients with encephalitis, and efforts to standardize evaluations, should be prioritized in all cases to facilitate recovery and enhance quality of life,” Tiffany Braley, MD, associate professor of neurology at the University of Michigan and an MS/neuroimmunology specialist, told Healio Neurology.
Types of sleep disorders
Autoimmune encephalitis can affect any of the neural networks related to initiating or regulating sleep and lead to multiple sleep problems, according to the researchers. Muñoz-Lopetegi and colleagues wrote that sleep problems in autoimmune encephalitis “are most likely a manifestation of the effects of the antibodies or associated immune responses on their specific targets.”
The four major kinds of sleep disorders — insomnia, parasomnias, sleep-disordered breathing and hypersomnolence — can occur in patients with autoimmune encephalitis, according to the researchers. In addition, “sleep can be altered in many ways” for these patients, leading to a wide array of symptoms.
In anti-NMDA receptor encephalitis, for example, up to 90% of patients had insomnia at onset that was not accompanied by daytime sleepiness at the peak of the disease, the researchers wrote. During recovery, many patients experienced hypersomnia that persisted after discontinuing antipsychotics, antiepileptics, benzodiazepines or other medications, which researchers said suggested that “hypersomnia forms part of the disease.”
Patients require symptomatic treatment for sleep disorders along with immunotherapy, according to the researchers. Neurologists can play a key role in treating sleep disorders among patients with autoimmune encephalitis by facilitating timely clinical sleep assessments, Braley noted.
“Neurologists who manage patients with known or suspected autoimmune encephalitis should routinely screen for sleep disturbances and initiate diagnostic workups if indicated,” she said.
Braley added that neurologists should refer those with complex cases or patients who do not respond to first-line treatments to sleep specialists.
Autoimmune encephalitis drugs can also affect sleep, according to Muñoz-Lopetegi and colleagues. For example, steroids can lead to insomnia and certain benzodiazepines can result in abnormal behaviors during sleep. These side effects are “probably under-reported,” the researchers wrote.
While current research demonstrates that “sleep disorders are frequent, often severe and usually [persistent] beyond the acute disease stage” in autoimmune encephalitis, more research is needed to determine the mechanisms that cause sleep disorders in this setting, the researchers wrote.
“Collaborative research that elucidates the prevalence and most common presentations of sleep problems across the spectrum of autoimmune encephalitides could enhance recognition of these sleep disorders and optimize treatment. Further work is also needed to evaluate the impact of early treatment of sleep disorders on the course of these neuroimmunological conditions,” Braley said. “The relative infrequency and complexity of autoimmune encephalitis illustrates a need for multicenter, multidisciplinary approaches that are informed by both neuroimmunology and sleep researchers.”