The research study, published in The Lancet Neurology, analyses an international cohort of 45 patients with anti-NMDAR encephalitis who presented a vegetative or similar state for at least 9 months. The follow-up, lasting an average of five years, has made it possible to describe the clinical evolution and prognosis of these patients in the long term.
Anti-NMDAR encephalitis is a serious autoimmune disease that affects the brain and can cause profound alterations in consciousness. In the most severe cases, patients may remain for long periods of time in intensive care units or suffering multiple medical complications, which generates great uncertainty about options for recovery.
The results of the study show that, despite this severity, approximately 66% of patients achieve significant functional improvement, and about a third achieve complete recovery. In addition, recovery can occur after very long periods, with improvements continuing over the years.
"One of the most significant aspects of the study is that it shows that such serious patients can recover, and that their recovery can be much slower than previously considered," explains Mar Guasp, researcher at IDIBAPS and first-named author of the study. “These data indicate that a prolonged state of altered consciousness does not necessarily imply irreversible brain damage in this disease."
The study also provides evidence of the high clinical complexity of these cases. The patients analysed required long hospital stays and suffered frequent complications such as infections, thrombotic events, or cardiovascular problems. However, many of them showed a favourable evolution in the long term.
For Josep Dalmau, head of the research group at IDIBAPS and the CaixaResearch Institute and senior researcher of the study, "these results have a significant impact for medical teams and families alike". As he points out, "it is necessary to be cautious when establishing prognoses and therapeutic decisions, because the possibility of recovery exists even after very long periods".
The results of the research question some established clinical concepts, such as when a treatment is considered ineffective. According to the authors, in this disease, the current criteria for refractory treatment may be too early and may not take into account the late recovery that many patients may experience.
In addition, the study highlights the need for a multidisciplinary and individualised approach for the management of these cases, as well as the importance of long-term studies to adequately evaluate the effectiveness of treatments.
The study has been funded by the Carlos III Health Institute and the ”la Caixa” Foundation, with nearly one million euros provided through the Health Research funding call.
Reference article
Complications, outcomes, and implications of a prolonged vegetative state in anti-NMDA receptor encephalitis: a retrospective international cohort study. Mar Guasp et al. Lancet Neurol 2026; 25: 368–78
