# A network analysis of lifetime stressor exposure, mental health, well-being, and immune cell mobilisation to acute stressors in young adults

## TL;DR

This study shows how early life stress affects mental health and immune responses to stress in young adults.

## Contribution

The study links lifetime stressor exposure to immune cell mobilization in response to acute stress in young adults.

## Key findings

- Frequent and severe early life stress increases susceptibility to adult stressors and mental health symptoms.
- Poor mental health negatively affects immune cell mobilization during acute stress.
- Lifetime stressor exposure is a key factor in immune and clinical health outcomes.

## Abstract

Many young adults experience mental ill-health which is increasing over time. From a theoretical perspective, the accumulation of stressors experienced over the lifespan may be an important factor in influencing the mental health and well-being of young adults. Although continued exposure to stressors can negatively impact aspects of immunity, researchers have yet to examine how lifetime stressor exposure (i.e., frequency and severity) influences mental ill-health and well-being, and how these states subsequently affected immune cell mobilisation in response to a laboratory-based social stressor in young adults. Eighty-six participants (Mage = 23.31 years, SD = 4.94) completed an online questionnaire which assessed their exposure to lifetime stressors, symptoms of depression and anxiety, and levels of well-being. Next, participants completed the Trier Social Stress Test while immunological (i.e., lymphocytes, monocytes and neutrophils) data were collected immediately pre and post the test. Results revealed that the more frequent and severe stressors experienced during early life rendered individuals more susceptible to stressors during adulthood, which positively influenced symptoms of depression and subsequent anxiety. These aspects then deterred well-being, which negatively affected immune cell mobilisation to the acute stressor. The results highlight the potential importance of assessing lifetime stressor exposure for researchers and clinicians aiming to study the social-environmental drivers of poor immune and clinical health.