Proportional Overrepresentation of Gender-Diverse Identities in Two US-Based Autistic Adult Samples from the SPARK Database

Background: Previous literature indicates a proportional overrepresentation of both autism and autistic traits within gender-diverse populations (individuals who experience their gender identity as different from their sex assigned at birth). Emerging but limited evidence also suggests a proportional overrepresentation of gender-diverse identities in autism. To our knowledge, this is the first study to report gender diversity prevalence in autistic adults in the United States. Methods: We report the prevalence of gender diversity within two well-characterized samples of autistic adults recruited from SPARK (Simons Foundation Powering Autism Research for Knowledge), the largest online research database of autistic individuals to date. This study includes both an original sample (Dataset 1, n = 205) and a replication sample (Dataset 2, n = 243). In addition, we looked at the co-occurrence of anxiety and/or mood disorders with gender-diverse identities. Results: We found that 16.1% of autistic adults in Dataset 1 and 19.8% of autistic adults in Dataset 2 were gender diverse. This compares with prior findings of 0.5% to 4.5% in the general adult population. Autistic participants who were gender diverse, compared with those who were not, were up to six times more likely to report diagnosed anxiety and/or mood disorder(s). The finding of proportional overrepresentation of gender diversity in autistic individuals is consistent with reports from other countries, and higher than some previous estimates (e.g., 15%). Conclusion: These findings point to the necessity for autism research to take gender identity into account in addition to sex assigned at birth, and to pay particular attention to the mental health challenges that gender-diverse autistic individuals may face. These important steps will lead toward increased understanding of the needs of gender-diverse autistic individuals and ways to improve care. Community Brief Why is this an important issue? People who are gender diverse (i.e., individuals who experience their gender identity as different from their sex assigned at birth) are more likely to be autistic or to have autistic traits than those who are cisgender (individuals who experience their gender identity as the same as their sex assigned at birth). Some research also suggests that autistic individuals are more likely to be gender diverse than those who are not autistic. However, as far as we know, no studies have looked at the proportion of autistic adults in the United States who are gender diverse. What was the purpose of this study? We looked at the rates of gender diversity in autistic adults in the United States. We also examined the rates of anxiety and mood disorders in these adults to see whether there was a difference in rates in the gender-diverse compared with the cisgender autistic adults. What did the researchers do? We looked retrospectively at the data from two online studies, which asked autistic and nonautistic adults about their gender identity and their sex assigned at birth. The researchers also asked whether they had received a diagnosis of an anxiety and/or mood disorder and compared these numbers in the cisgender and gender-diverse individuals. What were the results of the study? We found that a larger percentage of autistic adults were gender diverse compared to percentages reported in nonautistic individuals in the general adult population. We also found that autistic gender-diverse individuals were more likely to report diagnosed anxiety and/or mood disorders than autistic cisgender adults. What do these findings add to what was already known? This work adds to existing knowledge about the rates of gender-diverse identities in autistic adults in the United States. The results also add further information about the different rates of anxiety and mood disorders among gender-diverse and cisgender autistic adults. What are potential weaknesses in the study? First, we did not formally compare the nonautistic adults with the autistic samples since not all individuals in the nonautistic samples resided in the United States. Second, some wording on the survey questions does not align with current practices in the field. Third, we recognize the importance of engaging autistic and gender-diverse collaborators throughout the research process. We acknowledge that not having a diverse array of perspectives is a limitation of the study. How will these findings help autistic adults now or in the future? These findings will encourage autism researchers to study gender identity in addition to sex assigned at birth since many autism research studies group participants using only “sex” or “gender” and do not report on both. This would allow for improved understanding of gender-diverse autistic individuals and their unique experiences. Our findings also highlight the need for future research to find out more about the needs and challenges experienced by gender-diverse autistic individuals as well as strategies for improving care.