Monday, 24 October 2016

Bipolar disorder and the autism spectrum continued

In a previous post on this blog I talked about an important paper by Vannucchi and colleagues [1] summarising the state of the peer-reviewed research (up to 2014) on bipolar disorder and Asperger syndrome (AS). Today, I'm adding to the conversation on this important topic by introducing two papers to the discussions: the first by Xenia Borue and colleagues [2] and the second by Ahmad Abu-Akel and colleagues [3] covering the longitudinal course of bipolar disorder (BD) in relation to autism and the appearance of autistic and other traits in relation to cases of BD respectively.

Bipolar disorder (BD) previously known as manic depression is a condition affecting mood and specifically how it can 'swing' between extremes of depression and mania. There are a couple of different 'types' of BD reflective of how such mood swings can sometimes centre more on one aspect of BD over the other. As per the Vannucchi findings, the experience of BD may not be uncommon to the autism spectrum - "BD prevalence in adults with AS ranges from 6% to 21.4% of the cases" - but importantly: "is often characterized by atypical presentation, making its correct identification particularly difficult." Keep that in mind for now.

The papers by Borue and Abu-Akel put a little more scientific flesh on to the discussions about autism and BD. Specifically, how in these days of increasing recognition that autism rarely appears in some sort of diagnostic vacuum (see here), comorbidity might have some pretty important effects on clinical presentation.

To discuss the Borue findings first... well, based on a cohort of some 360 youths diagnosed with various types of BD who were followed for around 9 years, authors "compared youth with and without ASD [autism spectrum disorder] on clinical presentation, percentage of time with mood symptomatology, and psychosocial functioning." Approximately 8% of their cohort "met DSM-IV criteria for Asperger disorder or pervasive developmental disorder-NOS (referred to here as ASD)" which is an important detail. Further: "Compared to youth with BD, the clinical presentation of youth with BD+ASD more frequently involved distractibility, racing thoughts, depressed mood, social withdrawal, and low reactivity of negative mood states." The 'distractibility' side of things tallies with the observation that comorbid "attention-deficit/hyperactivity" (akin to ADHD) was more frequent in this group too and might be important [4]. Insofar as longitudinal course (at least over about 9 years), authors note: "Significant amelioration of clinical symptoms occurred over time, suggesting that early recognition and treatment of mood disorders in youth with ASD may improve clinical outcomes."

The Abu-Akel group set out to "determine the expression of autistic and positive schizotypal traits in a large sample of adults with bipolar I disorder (BD-I), and the effect of co-occurring autistic and positive schizotypal traits on global functioning in BD-I." BD-I focuses more on the manic side of clinical presentation. Bearing in mind autistic and schizotypal traits were self-assessed, authors reported that nearly 50% of their BD cohort (~800 people recruited via the Bipolar Disorder Research Network) "showed clinically significant levels of autistic traits." Around a quarter of their group also showed potentially important schizotypal traits too. Interestingly: "In the worst episode of mania, the high autistic, high positive schizotypal group had better global functioning compared to the other groups" with the requirement for quite a bit more study in this area.

What could these collective results mean?

Well, first and foremost all the chatter about traits and behaviours 'overlapping' shines through in these results. ESSENCE may indeed extend quite a bit further than just in childhood (see here) and this has some important implications for preferential screening services when an autism diagnosis is suspected or given. Second, I'm struck by how important traits outside of the autism spectrum might be to the presentation of something like BD in those reaching clinical thresholds for autism. I'm yet more convinced that the increasingly important association being made between autism and ADHD for example (see here) is really, really important. Third, the idea that autistic and certain schizotypal traits might actually be useful when it comes to 'global functioning' in cases of BD-I is an eye-opener. This needs further investigation. Finally, treatment for BD exists and with no medical or clinical advice given or intended, should not be withheld on the basis of a comorbid autism diagnosis.

Timely and accurate diagnosis of BD when co-occurring alongside autism (or the presence of autistic traits) continues to be a priority. Not least because of the potentially far-reaching and sometimes extreme effects that BD can have (see here for example) potentially overlapping with some distressing figures noted alongside autism (see here). Yes, the presentation of BD might be slightly different when autism/autistic traits are included in the diagnostic mix, but clinicians and other health professionals need to be sensitive to such subtleties. Once again, screening is the first step of the process...


[1] Vannucchi G. et al. Bipolar disorder in adults with Asperger׳s Syndrome: a systematic review. J Affect Disord. 2014 Oct;168:151-60.

[2] Borue X. et al. Longitudinal Course of Bipolar Disorder in Youth With High-Functioning Autism Spectrum Disorder. Journal of the American Academy of Child & Adolescent Psychiatry. 2016. Oct 4.

[3] Abu-Akel A. et al. Autistic and Schizotypal Traits and Global Functioning in Bipolar I Disorder. Journal of Affective Disorders. 2016. Oct 3.

[4] Wang HR. et al. Prevalence and correlates of bipolar spectrum disorder comorbid with ADHD features in nonclinical young adults. J Affect Disord. 2016 Sep 28;207:175-180.

---------- Borue, X., Mazefsky, C., Rooks, B., Strober, M., Keller, M., Hower, H., Yen, S., Gill, M., Diler, R., Axelson, D., Goldstein, B., Goldstein, T., Ryan, N., Liao, F., Hunt, J., Dickstein, D., & Birmaher, B. (2016). Longitudinal Course of Bipolar Disorder in Youth With High-Functioning Autism Spectrum Disorder Journal of the American Academy of Child & Adolescent Psychiatry DOI: 10.1016/j.jaac.2016.08.011 Abu-Akel, A., Clark, J., Perry, A., Wood, S., Forty, L., Craddock, N., Jones, I., Gordon-Smith, K., & Jones, L. (2016). Autistic and Schizotypal Traits and Global Functioning in Bipolar I Disorder Journal of Affective Disorders DOI: 10.1016/j.jad.2016.09.059