Case series of autistic people diagnosed in adulthood: Factors leading to late diagnoses

An evolving understanding of autism spectrum disorder has led to an increase in the number of adults receiving their diagnosis in adulthood. A diagnosis that was missed in childhood can lead to adverse mental health outcomes. Additionally, when autism presents with co-occurring conditions, it creates a complicated clinical picture. This case series reports on the clinical history and circumstances leading to an adult autism diagnosis in six adults. Each of these people had complex diagnostic pictures that led to barriers in diagnosis. Following these six vignettes, reasons for the late diagnoses are synthesized. These reasons include gender, race and culture, access to trained diagnosticians, other co-occurring conditions, and an evolving understanding of autism. Finally, we offer specific recommendations for healthcare professionals identifying autism in adulthood. • Late diagnosed autistic people are often missed for a variety of reasons and sometimes have been misdiagnosed with other conditions. • This case series includes 6 different presentations of autistic people who are diagnosed later in life (adulthood). • Factors contributing to missed diagnosis include gender, race, culture, co-occurring conditions and access to healthcare systems. • Understanding nuanced presentations of autism will help to better understand the experiences of autistic people.