Increased Risk for Substance Use in Autism Spectrum Disorders

Substance use and related issues are often overlooked in those with autism spectrum disorders (ASD). Related issues can include substance use disorder (SUD), substance-related crimes, and deaths related to substance abuse. A recent study found that SUD screening is not part of the regular clinical assessments for individuals with ASD (Arnevik). This could be due to the assumption that substance use issues do not occur for those with ASD. However, in clinical settings, substance use problems have been observed among individuals with ASD, with a study finding that 30% of individuals with ASD also have substance use disorders (Sizoo et al., 2010).

In their study, Butwicka et al. (2016), aimed to address the lack of research on the risk of substance use issues among individuals with ASD. Though some studies, such as Ramos et al. (2013), have argued that substance use problems are not associated with ASD, few have compared the prevalence of SUD in individuals with ASD to non-ASD populations. Butwicka et al. also considered the comorbidity of ASD with ADHD and ASD with intellectual disabilities (ID) when looking at the rate of substance use related problems. In addition, to understand if genetic and environmental factors play a role in substance abuse and ASD, researchers studied the pattern of substance abuse among non-ASD relatives of individuals with ASD.

Included in their definition of substance use related problems, these researchers investigated SUD, conviction for crimes related to substance abuse, and substance abuse related death.

Researchers used Swedish population-based registers, which record individuals diagnosed with specific disorders or diseases within a geographic location. Butwicka et al. (2016) used these documents to explore the risk of substance use related problems among individuals diagnosed with ASD. They identified 26,986 individuals with ASD from 1973-2009 and their 96,557 unaffected relatives.

While the risk for substance use problems was highest among those with ADHD and ASD, they found that for individuals with ASD alone, there was a risk twice as large for developing SUD compared to individuals without ASD. The study emphasizes the importance of reducing tension and enhancing social skills in healthier ways for individuals with ASD. Additionally, the fact that siblings, half-siblings, and parents of individuals with ASD faced a higher risk of substance use related problems suggests shared genetic or environmental factors associated with substance abuse.

They analyzed those with ASD who were diagnosed with ADHD and ID before being diagnosed with substance use disorder. Individuals with ASD only and those with ASD and ADHD are on a comparable level in terms of the risk of substance use related problems.

One of the main questions that arises from this study is: why has the idea that individuals with ASD are less likely to engage in substance use persisted for this long?

One possibility is that substance use related issues among individuals with ASD were less common in the past, but there are factors that have caused an increase in the combined cases over time. There is evidence for this, such as trends that have shown an increase in substance use in general.

Another reason for this could be due to the cohort effect. Studies prior to 1996, with a narrower diagnostic criterion, may have excluded ASD patients with substance use problems or assigned other diagnosis instead. With the broadening of the diagnostic criteria and increasing prevalence of ASD, there is a likelihood of simply diagnosing more people with ASD than who would have been in the past.

The study provides a strong overall design, with a large population and data from numerous databases. Moreover, their statistical analysis accounted for comorbidities and as mentioned above, their analysis included various associations. The study is also quite unique as not a lot of research has been done on this subject. There are numerous considerations that factor into the analysis of the results and the study does a decent job of addressing all of them. However, it is important to note that the data they do analyze comes from those who are in regular contact with mental health agencies and people who are known to have ASD. Furthermore, even though they claim to only look at ASD and its relation to substance use issues, it is impossible to rule out the possibility that there are undiagnosed comorbidities that may have influenced the data. As mentioned above, the familial aspect is hard to completely understand and some of the findings may rely on assumptions. Lastly, as this study was conducted using Swedish data, it would be interesting to conduct similar studies in the U.S. and other countries in order to observe differences or similarities among the results. This would be especially interesting as the rate of substance use and autism awareness differs by country.

Based on the results, it is clear that there is a need for research into preventative measures against substance use disorder within ASD populations. As ASD frequently co-occurs with ADHD or ID, the factors that contribute to this interaction needs to be investigated. This highlights a need for a more comprehensive methodology towards psychiatric evaluations. This can help tailor treatment strategies to target needs of each individual.

References

Arnevik, E. A., & Helverschou, S. B. (2016). Autism Spectrum Disorder and Co-occurring Substance Use

Disorder – A Systematic Review. Substance Abuse: Research and Treatment, 10.

https://doi.org/10.4137/sart.s39921

Butwicka, A., Långström, N., Larsson, H., Lundström, S., Serlachius, E., Almqvist, C., … Lichtenstein,

P. (2016). 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

Ramos, M., Boada, L., Moreno, C., Llorente, C., Romo, J., & Parellada, M. (2013). Attitude and risk of

substance use in adolescents diagnosed with Asperger syndrome. Drug and Alcohol

Dependence, 133(2), 535–540. https://doi.org/10.1016/j.drugalcdep.2013.07.022

Sizoo, B., Brink, W. van den, Koerter, M., Eenige, M. G. van, Wijngarrden-Cremers, P. van, & Gaag, R.

J. van der. (2010). Treatment seeking adults with autism or ADHD and co-morbid Substance Use Disorder: Prevalence, risk factors and functional disability. Drug and Alcohol Dependence, 107(1), 44–50. https://doi.org/https://doi.org/10.1016/j.drugalcdep.2009.09.003

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https://www.additudemag.com/the-truth-about-adhd-and-addiction/