“You Become Yourself, Your Full Self, the True Self”: A Systematic Review of Neurodivergent Adults’ Experiences of Identity Reconstruction Following Diagnosis of Autism and/or ADHD in Adulthood

Background: Growing numbers of adults are being diagnosed as autistic or having ADHD later in life, leading to a range of emotional responses and queries around identity. This review explores the process of identity reconstruction in late-diagnosed autistic and ADHD adults, examining both shared and distinct aspects of identity in each group, to better understand how diagnosis affects self-perception and to guide future post-diagnostic support. Methods: Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Joanna Briggs Institute (JBI) guidelines, we entered search terms relevant to autism, ADHD, delayed diagnosis, and identity into multiple databases. After screening titles and abstracts, two raters reviewed full-text articles to determine their inclusion with substantial inter-rater reliability. We extracted and coded qualitative data, with themes identified through thematic analysis. Results: The search strategy identified a total of 6894 articles, of which 5470 were duplicates. Reviewers screened 1423 articles. A final set of 25 articles was identified, with 12 articles exploring ADHD diagnoses and 13 articles exploring autism diagnoses. Our thematic analysis of the articles suggests that individuals experience a profound reevaluation of their identity following diagnosis in adulthood. Three overarching themes were identified, reflecting experiences shared across autism and ADHD, as well as distinctions unique to each condition: 1. Reconfiguring the self; 2. Finding the self through others; and 3. Emotional integration of the self. Participants grappled with confusion, reinterpretation of past experiences, and developed a more authentic sense of self, a process that was facilitated through finding belonging among neurodivergent peers. Emotionally, this process required navigating grief, internalized stigma, and negative self-perceptions. Diagnosis was transformative, offering validation and empowerment to participants. Overall, the process of diagnosis appears to foster growth toward a more integrated identity. Conclusions: Findings from this review highlight both shared and condition-specific impacts on identity, highlighting a need for post-diagnostic support that acknowledges the identity-related impacts of diagnosis in both autism and ADHD. Current evidence largely reflects majority populations, highlighting a gap in understanding of how underserved groups, such as ethnic minorities, experience and negotiate identity after diagnosis. Clinicians should be aware of the need for community connection, self-acceptance, and informed decision-making about disclosure, and provide affirming, tailored care following diagnosis.