Minus any sweeping generalisations, I want to bring your attention to the recent paper by Ashy Rengit and colleagues  today, continuing a theme of case reports discussing autism co-occurring with a substance use disorder (SUD). A SUD is generally defined as where the use of one or more substances (drugs) with psychoactive properties leads to significant impairment or distress for a person. Although some people might envisage the use of illicit drugs as being the only way to receiving a diagnosis like SUD, the label also covers more 'everyday' drugs such as problematic alcohol use for example. Indeed, alcohol use disorder (AUD) has its very own category in DSM-5.
I appreciate that this topic is generally neither good dinner-table conversation nor particularly great when it comes to the public image of autism, but as per other discussions overlapping with this topic (see here) it would be folly to ignore it. That some of the characteristics accompanying the diagnosis of autism *might* play a hand in increasing the risk of developing a SUD  provides an important message on the value of screening for risk of SUD and where appropriate, educating and intervening early.
Rengit et al provide some useful discussions on the "risk factors which predispose individuals with ASD [autism spectrum disorder] to developing SUD" but I hasten to reiterate that sweeping generalisations are to be avoided, including the ideas of "a positive family history for substance misuse" and the suggestion that autism might be one 'phenotype' "previously reported to be associated with cannabis use"  for example.
"It is relaxing in general and provides an amount of happiness" is the explanation offered by Mr. A, the participant under inspection, when it came to explaining his history of alcohol use and abuse. His relationship with alcohol, we are told, began after he graduated from high school and thereafter escalated from "one or two beers per week in solitude" to "hard liquor and wine on a daily basis." There is a familiar theme included in the Rengit paper on how a 'vicious cycle' of anxiety and depression are "perpetuated by his psychosocial limitations" and how combined with chronic worry, a pattern related to his alcohol use may be emerging in conjunction with social circumstances "eliminating his motivation to leave the house." That some of the traditional strategies for overcoming depression and anxiety only previously "showed limited benefit" also provides a rationale for how alcohol might be part and parcel of a self-medication strategy in this case. Similar sentiments have been noted in other research on this topic . I might also bring to your attention the history of suicide attempt(s) reported by the authors as a consequence of "feeling overwhelmed by the new environment and social challenges" that college life brought and how it may also be relevant to discussions on the pathway to SUD in relation to autism. This is particularly relevant to some important discussions recently.
Accepting that different people have different ways and means bringing them to something like a diagnosis of SUD, the Rengit paper brings to light a potentially important but difficult issue linked to some autism. Given the increasing numbers of people being diagnosed with autism (some of them quite late in life) and how in these times of continued austerity many are being left to fend for themselves, one might appreciate that cases of SUD linked to autism are only likely to increase further. This is on top of the idea that certain comorbidity that is over-represented in cases of autism might also increase the chances of something like SUD . That a SUD may further disadvantage people on the autism spectrum not just in terms of health but also in relation to obtaining and sustaining employment for example - "He was also fired from his job for being suspected of being intoxicated" - requires further study and action on both screening vulnerable populations and also managing/treating such issues quickly as and when they occur . Oh, and don't forget the burden of such additional issues on caregivers too ...
 Rengit AC. et al. Brief Report: Autism Spectrum Disorder and Substance Use Disorder: A Review and Case Study. J Autism Dev Disord. 2016 Mar 5.
 Tabata K. et al. Three cases of alcoholism with autism spectrum disorder. Alcohol Alcoholism. 2014 Sep;49 Suppl 1:i54.
 Stringer S. et al. Genome-wide association study of lifetime cannabis use based on a large meta-analytic sample of 32 330 subjects from the International Cannabis Consortium. Transl Psychiatry. 2016 Mar 29;6:e769.
 Clarke T. et al. Substance use disorder in Asperger syndrome: An investigation into the development and maintenance of substance use disorder by individuals with a diagnosis of Asperger syndrome. Int J Drug Policy. 2016 Jan;27:154-63.
 Pedersen SL. et al. The Indirect Effects of Childhood ADHD on Alcohol Problems in Adulthood through Unique Facets of Impulsivity. Addiction. 2016 Mar 21.
 Kronenberg LM. et al. Personal recovery in individuals diagnosed with substance use disorder (SUD) and co-occurring attention deficit/hyperactivity disorder (ADHD) or autism spectrum disorder (ASD). Arch Psychiatr Nurs. 2015 Aug;29(4):242-8.
 Kronenberg LM. et al. Burden and Expressed Emotion of Caregivers in Cases of Adult Substance Use Disorder with and Without Attention Deficit/Hyperactivity Disorder or Autism Spectrum Disorder. Int J Ment Health Addict. 2016;14:49-63.
Rengit AC, McKowen JW, O'Brien J, Howe YJ, & McDougle CJ (2016). Brief Report: Autism Spectrum Disorder and Substance Use Disorder: A Review and Case Study. Journal of autism and developmental disorders PMID: 26944591