Early-Life Adversity Due to Bereavement and Inflammatory Diseases in the Next Generation: A Population Study in Transgenerational Stress Exposure

Abstract

Emerging evidence suggests that trauma experienced in childhood has negative transgenerational implications for offspring mental and physical health. We aimed to investigate whether early-life adversity experienced as bereavement is associated with chronic inflammatory health in offspring. The study population included 3 generations of Swedish families with a base population of 453,516 children (generation 3) born in 2001-2012. Exposure was defined as the middle generation's (generation 2) experiencing bereavement in childhood due to the death of a parent (generation 1). Outcomes in generation 3 included 2 diagnoses of inflammatory diseases, including asthma, allergic diseases, eczema, and autoimmune diseases. Survival analysis was used to identify causal pathways, including investigation of mediation by generation 2 mood disorders and socioeconomic status (SES). We found that early-life bereavement experienced by women was associated with early-onset offspring asthma (hazard ratio = 1.15, 95% confidence interval: 1.08, 1.23); mediation analysis revealed that 28%-33% of the association may be mediated by SES and 9%-20% by mood disorders. Early-life bereavement experienced by men was associated with autoimmune diseases in offspring (hazard ratio = 1.31, 95% confidence interval: 1.06, 1.62), with no evidence of mediation. In conclusion, adversity experienced early in life may contribute to an increased risk of inflammatory diseases which is partly mediated by mood disorders and SES.

Keywords: adverse childhood experiences; allergy; asthma; bereavement; inflammatory disease; transgenerational stress.