On the "co-occurrence of autism and delinquency": no association for the majority

"The extant research shows that for most people with ASD [autism spectrum disorder] there is no association between ASD and delinquent behavior."

That was one of the primary conclusions reached in the literature review published by Alexa Rutten and colleagues [1] (open-access) looking at the collected peer-reviewed science from 1990 to 2015 on this topic. Boiling down the literature to 12 papers "five of which report the prevalence of delinquency in patients with ASD and seven the prevalence of ASD in a forensic population", authors reported on quite a lot of variability when it came to delinquency and offending behaviours but overall, offending behaviour was "lower in people with ASD than in the general population."

This is welcomed research. It reiterates what many people have already known/suspected, in that the label 'autism' for many is not typically associated with intentional delinquency or offending behaviour. As Rutten et al note: "many people with ASD have an overactive sense of right and wrong and are usually conscientious and unwilling to break the law." I should also point out that a diagnosis of autism is not however necessarily some kind of 'shield' when it comes to offending behaviour (see here and see here for a more recent example) or indeed, potential 'vulnerability' to becoming involved in specific offences (see here). But serious 'intentional' delinquency is not the norm; even that is, in the context of something like greater likelihood of contact with law enforcement agencies (see here).

There are still lessons to learn in this area of research and practice. Certain 'over-represented' comorbidity appearing alongside autism is still something to potentially consider [2] as per other findings (see here and see here). I say that without 'trying to pass the [diagnostic] buck'. Bearing in mind also how wide the autism spectrum is, specific diagnoses on the spectrum might also require further study as per the authors comments: "The prevalence of ASD diagnoses, particularly Asperger’s syndrome, in forensic settings is remarkable because it is much higher than the prevalence of ASD diagnoses in the general population." At this point I'll also refer you once again to the comprehensive review paper by Tom Berney [3] that mentions some of the potential how-and-whys of offending in the specific context of Asperger syndrome, again minus any sweeping generalisations. Recent media attention on previously undiagnosed Asperger syndrome in a prison context also makes for important and relevant reading too (see here) particularly where substance abuse is prominently mentioned (see here).

I would however question one rather sweeping statement made by Rutten and colleagues: "It is important to diagnose ASD carefully and to differentiate autism symptoms such as a lack of empathy from psychopathic traits". Lack of empathy and autism? Hmm, sounds a bit old hat to me...

I will again close with the point made that for the majority of people on the autism spectrum, the label is much more likely to be associated with law abiding rather than law breaking.

----------

[1] Rutten AX. et al. Autism in adult and juvenile delinquents: a literature review. Child and Adolescent Psychiatry and Mental Health. 2017; 11: 45.

[2] Newman SS. & Ghaziuddin M. Violent crime in Asperger syndrome: the role of psychiatric comorbidity. J Autism Dev Disord. 2008 Nov;38(10):1848-52.

[3] Berney T. Asperger syndrome from childhood into adulthood. Advances in Psychiatric Treatment. 2004. 10; 341-351.

----------

"a potential link between serious delinquency and later schizophrenia"

I was rather intrigued by the results reported by Nina Lindberg and colleagues [1] in their study designed to "investigate if serious delinquency was associated with future diagnoses of schizophrenia or schizoaffective disorder (here, broadly defined schizophrenia) among a nationwide consecutive sample of 15- to 19-year-old Finnish delinquents sent for a forensic psychiatric examination in 1989-2010."

I hadn't previously come across research directly linking delinquency - serious delinquency - with later schizophrenia diagnosis despite noting other research talking about other labels being potentially related to the extreme results of delinquency (see here) and onward some of those labels being potential risk factors for something like schizophrenia (see here).

Looking at the records of "313 delinquents with no past or current psychotic disorder" and around 1200 age- and sex-matched non-delinquents whose details were also held on a central population registry, researchers followed them all "[un]till death, emigration or the end of 2015, whichever occurred first." The results put delinquents as a group at quite a bit more risk of subsequently being diagnosed with schizophrenia than non-delinquents (12% vs. ~1% respectively). The authors conclude that their results "supports the previous research indicating a potential link between serious delinquency and later schizophrenia" and that more investigation is needed into the hows-and-whys of such a relationship.

Having already mentioned the slightly more indirect link between attention-deficit hyperactivity disorder (ADHD) and risk of offending behaviour (minus any sweeping generalisations) and ADHD and risk of schizophrenia, there could be lessons to be learned about the link between serious delinquency and schizophrenia. Also, minus further generalisations, I'm also wondering if some of the 'habits' perhaps more readily observed in delinquents (e.g. illicit drug use) could potentially be additional risk factors for a diagnosis of schizophrenia [2]. Minus any psycho-babble explanations, the rise and rise of scientific evidence pointing to various psychosocial factors as also being risk factors for schizophrenia [3] may additionally come into play, together with an understanding that elements of the parental home also may play a key role in cases of delinquency [4]. In short, there are several potentially important areas that could provide key research directions in this intriguing area.

----------

[1] Lindberg N. et al. Serious delinquency and later schizophrenia: A nationwide register-based follow-up study of Finnish pretrial 15- to 19-year-old offenders sent for a forensic psychiatric examination. Eur Psychiatry. 2017 May 15;44:173-178.

[2] Marconi A. et al. Meta-analysis of the Association Between the Level of Cannabis Use and Risk of Psychosis. Schizophr Bull. 2016 Sep;42(5):1262-9

[3] Larsson S. et al. High prevalence of childhood trauma in patients with schizophrenia spectrum and affective disorder. Compr Psychiatry. 2013 Feb;54(2):123-7.

[4] Fernández-Suárez A. et al. Risk Factors for School Dropout in a Sample of Juvenile Offenders. Front Psychol. 2016 Dec 26;7:1993.

----------