A genome-wide study conducted by scientists at Yale School of Medicine and other research institutions found that economic status mediates negative associations of cognitive ability and educational attainment in people with posttraumatic stress disorder (PTSD).
The study, published on JAMA Network Open, considered data generated by more than 1.13 million participants.
PTSD is a psychological condition that can occur after a person is exposed to trauma. Prospective studies have determined that many variables previously considered outcomes of trauma, such as cognitive ability and educational attainment, may actually be pre-trauma risk factors.
Cognitive ability and educational attainment are well-known to have a negative association with posttraumatic stress disorder. However, it is unclear whether cognitive ability and educational attainment are pre-trauma risk factors or a consequence of PTSD pathogenesis.
The researchers, members of the Psychiatric Genomics Consortium for PTSD, observed that the genetic score associated with educational attainment was negatively associated with PTSD. Conversely, PTSD genetic score was not associated with educational attainment. Limited evidence of genetic correlation was observed between cognitive ability and PTSD.
“This study provides a better understating of the relationship of PTSD with several risk factors. In particular, our results show that the negative association of cognitive ability and educational attainment is completely mediated by economic status,” said Renato Polimanti, PhD, MSc, Assistant Professor of Psychiatry and the study’s lead author. “Excluded the role of brain mechanisms of cognitive skills in PTSD pathogenesis, further studies will be needed to clarify which are the factors related to the economic status that increase the risk of PTSD.”
To verify whether the association between education and PTSD was driven by other risk factors, the researchers tested the combination of multiple risk factors, including risk-taking behaviors, propensity to trauma, and economic status. While risk-taking behaviors and trauma propensity are independent of the education-PTSD association, economic status appears to be the variable linking education and PTSD.
The analysis of transcriptomic profiles in different tissues and cell types showed that brain regulatory processes associated with cognitive ability and educational attainment seem to not be involved in the predisposition to PTSD.
Joel Gelernter, MD, Foundations Fund Professor of Psychiatry and Professor of Genetics and of Neuroscience; Director, Division of Human Genetics (Psychiatry), was the study’s senior author.