0422 Recent or Lifetime Stressor Exposure? Associations With Insomnia Symptom Severity

Introduction Insomnia is a highly prevalent disorder, impacting roughly 12% of the population. Recent stressor exposure has been implicated as a precipitating factor in the onset of insomnia. However, considering the importance of lifetime stressor exposure in other stress-related pathology, it is possible that lifetime stressor exposure drives insomnia, rather than recent stressor exposure. Lifetime stressor exposure may serve as predisposing factor, increasing risk of insomnia onset via enduring stress system changes. This study aimed to investigate the association between recent stressor exposure, lifetime stressor exposure, and insomnia symptoms severity. Methods Data was collected from 134 participants (55% female, Mage = 19.83, 28% Black/African American, 34% Latinx/ Hispanic, and 39% White) completed a laboratory visit consisting of questionnaires. The Stress and Adversity Inventory (STRAIN) was used to assess lifetime and recent (past 3 months) stressor exposure and perceived stressor severity. Insomnia symptoms were measured using the Insomnia Severity Index (ISI). Race and sex were included as covariates in all models. Results We hypothesized that lifetime stressor exposure and perceived lifetime stressor severity but not recent stressor exposure or severity, would be associated with greater insomnia severity. Results from the regression model showed that recent stressor exposure was negatively associated with insomnia symptom severity (b = -1.37, SE = 0.53, p = .01). Recent stressor severity was associated with greater insomnia symptom severity (b = 0.28, SE = 0.14, p = 0.04). Neither lifetime stressor exposure nor perceived lifetime stressor severity was associated with insomnia symptom severity. Conclusion Results suggest a counterintuitive negative relation between recent stressor exposure on insomnia severity, where more recent stressors is associated with less severe insomnia symptoms. However, greater recent stressor severity was associated with greater insomnia symptom severity. These findings suggest that recent stressor severity may be a better predictor of insomnia risk than both recent or lifetime stressor exposure. Support (if any)