B4193 - Examining the aetiology of alcohol use in autistic adults - 14/11/2022

B number: 
Principal applicant name: 
Evie Stergiakouli | MRC IEU
Miss Stephanie Page
Title of project: 
Examining the aetiology of alcohol use in autistic adults
Proposal summary: 

Alcohol use is a major issue for the UK healthcare system. Little is known about the link between autism and alcohol use, but preliminary research suggests that autistic adults who drink are twice as likely to become dependent as their neurotypical counterparts (1; 2). This does not seem to be the case for autistic adolescents (but existing studies are limited methodologically by small sample sizes and cross-sectional study designs) (3). Using longitudinal population-based studies to understand alcohol use in autistic adolescents going into young adulthood could address these issues. Doing this while controlling for potential confounders will help us understand what influences the development of this association over time.
Further, it is unclear whether genetics influence this association. Exposure-outcome associations are often estimated without accounting for genetic confounding in epidemiological studies, leading to potential inaccuracies (4). A genetic variant in the autism susceptibility candidate 2 gene (AUTS2) has been found to be associated with alcohol consumption (5), but it is unclear whether there are other genetic variants associated with autism that influence alcohol use. To assess this, we could calculate polygenic risk scores for autism and explore their association with alcohol use. This will help us ascertain whether genetic overlap plays a role in the aetiology of this association and potentially improve the accuracy of future causal estimates.
(1) Bowri, M., Hull, L., Allison, C., Smith, P., Baron-Cohen, S., Lai, M. C., & Mandy, W. (2021). Demographic and psychological predictors of alcohol use and misuse in autistic adults. Autism, 25(5), 1469–1480. https://doi.org/10.1177/1362361321992668

(2) Butwicka, A., Långström, N., Larsson, H., Lundström, S., Serlachius, E., Almqvist, C., Frisén, L., & Lichtenstein, P. (2017). Increased Risk for Substance Use-Related Problems in Autism Spectrum Disorders: A Population-Based Cohort Study. Journal of Autism and Developmental Disorders, 47(1), 80–89. https://doi.org/10.1007/s10803-016-2914-2

(3) Arnevik, E. A., & Helverschou, S. B. (2016). Autism spectrum disorder and co-occurring substance use disorder - A systematic review. In Substance Abuse: Research and Treatment (Vol. 10, pp. 69–75). Libertas Academica Ltd. https://doi.org/10.4137/SART.S39921

(4) Pingault, J. B., Rijsdijk, F., Schoeler, T., Choi, S. W., Selzam, S., Krapohl, E., O’Reilly, P. F., & Dudbridge, F. (2021). Genetic sensitivity analysis: Adjusting for genetic confounding in epidemiological associations. PLOS Genetics, 17(6), e1009590. https://doi.org/10.1371/JOURNAL.PGEN.1009590

(5) Schumann, G., Coin, L. J., Lourdusamy, A., Charoen, P., Berger, K. H., Stacey, D., Desrivières, S., Aliev, F. A., Khan, A. A., Amin, N., Aulchenko, Y. S., Bakalkin, G., Bakker, S. J., Balkau, B., Beulens, J. W., Bilbao, A., de Boer, R. A., Beury, D., Bots, M. L., … Elliott, P. (2011). Genome-wide association and genetic functional studies identify autism susceptibility candidate 2 gene (AUTS2) in the regulation of alcohol consumption. Proceedings of the National Academy of Sciences of the United States of America, 108(17), 7119–7124. https://doi.org/10.1073/PNAS.1017288108

Impact of research: 
To our knowledge, this will be the first ever longitudinal study to look at alcohol use in autistic adolescents going into young adulthood. This will help us understand whether associations emerge at a certain age and the direction of any association. It will also help us understand whether any association is driven by confounders. Further, the second study will help us understand whether genetics influence the association between autism and alcohol use. This could help to improve future causal estimates and thus our understanding of this relationship.
Date proposal received: 
Monday, 7 November, 2022
Date proposal approved: 
Monday, 14 November, 2022
Epidemiology, Addiction - e.g. alcohol, illicit drugs, smoking, gambling, etc., Developmental disorders - autism, Statistical methods, Statistical methods