Characteristics and Outcomes of Autonomic Dysfunction in Anti-NMDAR Encephalitis

Abstract

Background To explore the characteristics and prognosis of autonomic dysfunction and paroxysmal sympathetic hyperactivity (PSH), and evaluate the efficacy of drugs used to suppress PSH episode in anti-NMDAR encephalitis patients.MethodsPatients who met the diagnostic criteria of anti-NMDAR encephalitis were enrolled from January 2012 to August 2018 and followed up. PSH was diagnosed according to the PSH-Assessment Measure. The demographics data, clinical features, main accessory examinations, treatments, and long-term outcomes were prospective collected and analyzed. ResultsA total of 132 anti-NMDAR encephalitis patients were enrolled, 27.3% of patients experienced autonomic dysfunction, of which cardiac autonomic dysfunction (77.8%) was the most common subdivisions. Of the patients, 9.1% had probable PSH, tachycardia, tachypnea, and hypertonia (100%) were the most common symptoms of PSH. Patients with a higher incidence of ovarian teratoma, mechanical ventilation, intensive care unit admission, and elevated levels of CSF glucose, and higher CSF NMDAR antibody titers were more likely to exhibit autonomic dysfunction or PSH. Diazepam and phenobarbitone were commonly used drugs to control PSH episodes in patients without prior sedative drugs and the overall efficacy was 90.0%. However, the efficacy of monotherapy dropped to 69.6% and approximately half of episodes need a combination of drugs to control symptoms in PSH patients with prior sedative drugs. No significant difference was observed in the prognosis between the autonomic dysfunction group and the non- autonomic dysfunction group or PSH group and non-PSH group after 6 months and during long-term follow-up. However, patients with cardiac autonomic dysfunction had a poor prognosis at 6 months.Conclusion PSH is a common clinical condition in patients with anti-NMDAR encephalitis, especially in severe cases, and the clinical management of PSH can be assisted by several acute drug administered therapies. Patients with autonomic dysfunction or PSH do not seem to compromise their neurological recovery despite a longer hospital stay.