Wednesday, 1 March 2017

Sex and age might affect comorbidity profiles in autism

The paper by Supekar and colleagues [1] provides some food for thought today specifically with the idea that comorbidity profiles accompanying autism might be influenced by age and gender in mind.

To quote: "These results highlight crucial differences between cross-sectional comorbidity patterns and their interactions with sex and age, which may aid in the development of effective sex- and age-specific diagnostic/treatment strategies for ASD [autism spectrum disorder] and comorbid conditions."

From a starting point assuming that the diagnosis of autism rarely exists in some sort of diagnostic vacuum (see here), researchers set about looking at comorbidity patterns for quite a few conditions/labels "using cross-sectional data from 4790 individuals with ASD and 1,842,575 individuals without ASD." The sorts of things that looked for were not uncommon to discussions about comorbidity accompanying autism on this blog (epilepsy, attention-deficit hyperactivity disorder (ADHD) and "bowel disorders" for example). The variables of sex (gender) and age were also included in the research mix.

Bearing in mind that sweeping generalisations about autism comorbidity profiles are not required, the authors highlighted a couple of important points. First: "Epilepsy, ADHD, and CNS/cranial anomalies showed exceptionally large proportions in both male (>19%) and female (>15%), children/adolescents with ASD. Notably, these prevalence rates decreased drastically with age in both males and females." This is interesting. With a rather large research gap quite visible when it comes to the concept of ageing and autism (see here), the author's data seems to be suggesting that the burden of comorbidity (some comorbidity) might decline as people diagnosed on the autism spectrum get older. Yes, the words "cross-sectional comorbidity" are important (more longitudinal study is required where people are 'followed' as they age) and there is no doubt that intervention to manage diagnoses such as epilepsy (and/or seizure disorder) probably plays a hand in presentation, but more investigation is certainly required.

Next: "the prevalence of schizophrenia increased with age affecting a disproportionately large number of older (≥35 year) adult males (25%), compared to females (7.7%), with ASD." Two points are made here: (a) rates of schizophrenia might be affected by sex, and (b) age might play a role in the presentation of schizophrenia in the context of autism. This follows a theme re-emerging over these past few years suggesting that the autism and schizophrenia spectrums might not be as separate and independent as many might believe (see here and see here). Quite a lot of [research] focus has been directed at some of the signs and symptoms of schizophrenia with [some] autism in mind (see here for example) and perhaps queries whether history was 'too quick' to try and distance the two labels from each other (were Mildred Creak and colleagues correct?). Given the significant issues potentially linked to a diagnosis of schizophrenia (see here) in terms of health inequality and the like (something also sadly not unfamiliar to autism too), the onus should surely be to screen (and keep screening) for schizophrenia when autism is present into adulthood? Said screening could be preferentially driven by the Supekar findings taking into account that caveat about not over-generalising findings.

I'm gonna stop there with discussing these results so as not to over-analyse the findings. The important take-away point is that autism is generally not a 'stand-alone' condition and that age and gender might have some important roles to play when it comes to at least some comorbidity.

Music: something lively I think so increase the volume please...


[1] Supekar K. et al. The influence of sex and age on prevalence rates of comorbid conditions in autism. Autism Res. 2017 Feb 11.

---------- Supekar K, Iyer T, & Menon V (2017). The influence of sex and age on prevalence rates of comorbid conditions in autism. Autism research : official journal of the International Society for Autism Research PMID: 28188687