Pharmacogenetics in Adults with ASD and ID
Genetic variation impacts drug metabolism in all adults. Our objective is to understand how we can optimism medications for adults with autism spectrum disorder (ASD) or intellectual disabilities (ID).
It is estimated that 1 to 2% of the population are affected by either intellectual disability (ID) or autism spectrum disorder (ASD) . They frequently require treatment with psychotropic medications (e.g., antipsychotics and antidepressants) for their aberrant behavior (e.g., irritability and aggression). Treatment of symptoms frequently involves antidepressant and antipsychotic medications where off-label use is a common problem.
The prevalence of prescribing psychotropics in UK varies from 49% to 89% in ID. In Canada, one study consisting of 51,881 individuals with ID noted that 39.2% of patients were prescribed antipsychotic medications to treat challenging behaviours. Polypharmacy and excessive dosages are common in ID (11-60%) and ASD (5.4-54%)
There is ample evidence that gene variants affect the activities of cytochrome P450 enzymes and thereby affecting response and side effects to medications which are corresponding substrates. The use of pharmacogenomics (PGx) testing has been repeatedly associated with favorable treatment outcomes in psychiatric patients.
However, there is still a limited number of PGx studies as in adults with ID/ASD
Did you know?
In Canada, one study consisting of 51,881 individuals with ID noted that 39.2% of patients were prescribed antipsychotic medications to treat challenging behaviours.
Current Studies
Our Approach
Databases: MEDLINE, Embase, and PsycINFO
Search terms: antipsychotic-, autism spectrum disorder-, intellectual disability-,
and pharmacogenomic-related terms
Inclusion criteria:
(1) peer-reviewed original articles
(2) investigating the association between any gene variants and serum/plasma concentrations or dosages of any psychotropics, treatment response to any psychotropics, and adverse effects of any psychotropics
(3) published in English until February 29th of 2020
Our Results
The Take-Away
There is limited data available on PGx in individuals with ASD/ID and in particular in adults. Additional PGx studies for psychotropic treatment in ASD/ID across age groups are warranted.
Selected Publications
Pharmacogenomic Studies in Intellectual Disabilities and Autism Spectrum Disorder: A Systematic Review. [in press]
Yoshida K, Koyama E, Zai CC, Beitchman JH, Kennedy JL, Lunsky Y, Desarkar P*, Müller DJ*. Can J Psychiatry.