Previous research has shown that exposure to adversity, especially when traumatic events occur during sensitive periods of immunologic development, is associated with worse health outcomes, including increased risk for psychiatric illness and neurodegenerative disorders, as well as premature mortality. Inflammation appears to be a major pathway by which exposure to adversity increases vulnerability to disease later on. While we know that early childhood – especially the first five years of life – is a time of increased vulnerability to adverse events, we know less about stages in adulthood that may be associated with increased susceptibility to adversity in terms of future health outcomes.
Because of the dramatic changes in the immune system that occur during pregnancy, it has been hypothesized that pregnancy may constitute a time of increased vulnerability to adversity.
How does trauma impact immune function in women? And how might we examine changes in immune function as biomarkers to more precisely recognize and address trauma exposure in psychiatric care?
A recent study conducted by researchers at UCSF Psychiatry tested whether retrospective reports of adversity during early childhood or pregnancy were associated with markers of inflammation. Study participants were drawn from an ethnically diverse cohort of low-income women (n=53) seeking family-based trauma treatment following exposure to interpersonal violence. Researchers conducted structured interviews with study participants to gather information about early life adversity (trauma exposure at or before the age of 5), adversity experienced during pregnancy, and total lifetime adversity. To examine these variables in relation to immune function, researchers tested for M1/M2 macrophage polarization, as well as endotoxin tolerance (ET). (M1/M2 is a marker of enhanced inflammatory reactivity while ET is a marker of suppressed inflammatory reactivity.)
After adjusting for socioeconomic status, demographics, and psychopathology, the study indicates that higher experienced psychosocial adversity in early life, as well as during pregnancy, were both associated with higher M1/M2 gene expression, whereas higher lifetime adversity was associated with lower immunosuppressive gene expression.
The results of this study illuminate novel biomarkers for identifying exposure to adversity and promise the possibility of more precise diagnostic, as well as treatment avenues, for women who have experienced interpersonal violence. While prior research had only identified early childhood as an immunologically sensitive window, this study highlights pregnancy as another sensitive period for immune development. During these sensitive periods, exposure to adversity may lead to sustained changes which increase risk for worse health outcomes.
Given that exposure to interpersonal violence during both early childhood and pregnancy may pose a long-term risk for worse health outcomes, the researchers call for more robust phenotyping in future studies to distinguish the impact of adversity during sensitive periods from total adversity experienced across a woman’s lifespan.
Anne Nields, BS
Aschbacher K, Hagan M, Steine IM, Rivera L, Cole S, Baccarella A, Epel ES, Lieberman A, Bush NR. Adversity in early life and pregnancy are immunologically distinct from total life adversity: macrophage-associated phenotypes in women exposed to interpersonal violence. Transl Psychiatry. 2021 Jul 20;11(1):391. Free article.