Prevalence of Autism Spectrum Disorder and Attention-Deficit Hyperactivity Disorder Amongst Individuals with Gender Dysphoria: A Systematic Review

Autism spectrum disorders (ASD) and attention-deficit hyperactivity disorder (ADHD) can compromise health and may be more prevalent amongst individuals with gender dysphoria (GD). Symptoms such as attention or social difficulties can impact assessment of GD, understanding of health information, and engagement in clinical care. To ensure neurodevelopmental conditions are adequately considered in gender health services, we aimed to systematically review the literature examining the prevalence of ASD and ADHD amongst individuals with GD. In this systematic review based on the PRISMA guidelines. MEDLINE and PsycINFO databases were searched for studies examining the prevalence of ASD and/or ADHD in individuals with GD or investigated the rate of GD in cohorts with ASD or ADHD. All English peer-reviewed publications were included. The search strategy identified 179 studies. After applying exclusion criteria, a total of 30 studies were identified, 22 studies which examined the prevalence of ASD or ADHD in people with GD. A further 8 studies examined the reverse; prevalence of GD in people with ASD. The few studies employing diagnostic criteria for ASD suggest a prevalence of 6-26% in transgender populations, higher than the general population, but no different from individuals attending psychiatry clinics. Few studies examine prevalence of ADHD. Low-level evidence exists to suggest a link between ASD and GD. Further population-based and controlled studies using diagnostic criteria for ASD and ADHD are required.