Neurodivergent Characteristics and Treatment Outcomes for Patients and Carers: A Secondary Analysis of the TRIANGLE Trial for Anorexia Nervosa

OBJECTIVE: Neurodivergent characteristics, such as autistic and obsessive-compulsive features, may be associated with poorer treatment outcomes in anorexia nervosa (AN). We used data from the TRIANGLE trial to examine rates of neurodiverse features and their associations with 18-month outcomes for patients and their carers. METHOD: Patients (N = 370) enrolled in TRIANGLE completed baseline screening for autistic (AQ-10) and obsessive-compulsive features (OCI-R) and self-reported lifetime comorbid diagnoses. Patient and carer outcomes were measured at intervals up to 18 months. RESULTS: 27.1% of patients reported high autistic features, 61.6% reported high obsessive-compulsive features, and 21.7% reported high scores on both measures; 5.4% self-reported Autism Spectrum Disorder (ASD) diagnosis, and 16.2% self-reported Obsessive-Compulsive Disorder (OCD) diagnosis. Patients with high autistic or obsessive-compulsive features had higher levels of eating and general psychopathology and poorer work and social adjustment at both baseline and 18 months later. However, those with high obsessive-compulsive characteristics had greater improvements on these outcomes over time. Carers of those with high autistic or obsessive-compulsive features reported similar caregiving skills and psychological distress at baseline. Over time, those supporting patients with high autistic features reported greater reductions in psychological distress. Those supporting patients with high obsessive-compulsive features reported greater improvements in caregiving skills. DISCUSSION: We observed high rates of neurodiversity in our large cohort of patients with AN, and in some cases, more robust improvement relative to those with lower scores on neurodiversity dimensions. Greater consideration of neurodiversity in AN treatment may enhance benefit for patients and carers.