Dynamics of PTSD and autonomic symptoms in a longitudinal US population-based sample

Abstract: Objective: Posttraumatic stress disorder (PTSD) symptoms can co-occur with somatic symptoms, associations which may be partly due to threat-responsive changes in the autonomic nervous system. Prior studies support between-person associations of elevated autonomic symptoms with higher PTSD severity. However, there is a need to distinguish between- and within-person variation in symptoms over time. Method: This study used a latent growth model with structured residuals to examine the dynamics of PTSD and autonomic symptoms in a U.S. population-based sample. Participants were 475 adults with an exposure to a potentially traumatic stressor (M-age = 47.89 +/- 17.46; 62.9% female; 64.0% Caucasian, 14.3% Black or African American, 13.5% Hispanic, 2.3% Asian, 5.9% mixed race or ethnicity). Data were collected over four time points spaced approximately 1.5 months apart between July 2020 and January 2021 during the COVID-19 pandemic. PTSD and autonomic symptoms were measured using the Abbreviated Post-Traumatic Stress Disorder Checklist and the supradiaphragmatic symptoms subscale of the Body Perception Questionnaire-Short Form. Results: Latent PTSD and autonomic symptoms were positively associated (beta = .499, SE = .048). At each wave, within-individual elevations in PTSD symptoms co-occurred with elevations in autonomic symptoms (beta range: .221-.317). At several time points, elevated PTSD symptoms also predicted future elevations in autonomic symptoms (beta range: .215-.304, p < .05). A history of childhood maltreatment was associated with higher PTSD (beta = .309, p < .001) and autonomic symptom intercepts (beta = .335; p < .001). Conclusions: Results support the linkage between PTSD and autonomic symptoms over time and suggest that elevations in PTSD symptoms may precede future autonomic symptoms.