Longstanding eating disorders: insights and innovations in severe and enduring illness.

This review synthesizes recent findings on recent developments in the understanding and treatment of longstanding eating disorders (L-ED). Following a systematic search 42 papers were identified that included 5 scoping or systematic reviews. The majority were about phenomenology and treatment. Co-design and perspectives of people with lived experience expertise were common. Research on conceptualization suggests some consistency that duration is a necessary but insufficient defining feature, and to broaden from a symptom focus to the inter- and intra-personal experience of L-ED. There has been little progress however on a consensus for the defining features or the aetiological understanding of L-ED or longstanding anorexia nervosa (L-AN). There are several new collaborative and person-centred models of care and therapeutic approaches, alongside developments in treatments, mostly biological however, and most of L-AN, e.g. ketamine, repetitive transcranial magnetic stimulation (rTMS) and deep brain stimulation (DBS). There remains an acute need to test these in controlled trials. L-EDs continue to present unique challenges. The involvement of people with lived experience expertise in research has supported the increasing emphasis on exploring improved longer-term outcomes and meaningful trajectories of recovery, with personalized and integrated approaches to care being the new holy grail.