Gabrielle Michel, Winner of the 2021 Three-Minute Talks Competition

Transcript

GABRIELLE MICHEL: Hi, my name is Gabrielle Michel. A substantial literature has examined the relationship of anger and aggression to cardiovascular events, such as heart attack in the general population. On a much smaller scale, this relationship has been studied in the context of serious mental illness. 

We asked what we think is a novel question: Do cardiovascular disease genetics predict aggression-related behaviors in a schizophrenia sample? 

Genome-wide association studies identify genetic variants to find their association with traits. Polygenic scores then summarize this wide array of genetic information into single quantitative values. Our group derived polygenic scores for several cardiovascular risk variables from reference genome-wide association studies. 

After principal components analysis, I grouped these polygenic scores into composites for dimensions of cardiovascular disease risk, cardiac illness genetics, blood pressure genetics, diabetes genetics, and cholesterol genetics. We tested the association of these composite genetic scores with variables drawn from the branch's research and medical records of our participants reflecting aggressive behaviors, destructive behaviors, non-suicidal self-injury, and suicide behaviors.

I tested the association of the four genetic composite scores with the behavioral variables using binary logistic regressions and did parallel analyses by sex groups. I controlled for age, sex, and ethnicity. 

We found that physical aggression and non-suicidal self-injury are strongly related to serious cardiac genetics. The male portion of our sample entirely accounted for the physical aggression association, while we did not find this association in the females. The female portion of our sample drove the non-suicidal self-injury association with just an attenuated association for this behavior in the males.

In conclusion, we identified a novel association of cardiovascular genetics to aggression-related behaviors in a large schizophrenia sample. We found this association only for serious cardiac genetics and for physical aggression and self-injury, but not for the other genetic composite scores or the other behaviors. We also found an interesting divergent pattern of association based on sex. 

What's next for this project? We will look further at the mechanisms that might account for both cardiac and emotional dysregulation. Autonomic nervous system over-reactivity is one example of a candidate mechanism. We also will be delving further into self-harm and schizophrenia, specifically in females. 

Thank you for listening to my talk.