Abstract P221: Association of Posttraumatic Stress Disorder With Physical Activity Among Vietnam-Era Male Twin Veterans

Abstract

Introduction: Post-traumatic stress disorder (PTSD) can develop after a traumatic event and is associated with cardiovascular diseases (CVDs), but the mechanisms are not clear. Behavioral factors like physical activity (PA) may play a role if associated with PTSD, but few studies have examined whether PTSD may be associated with lower PA. By studying twins, we can examine this relationship and adjust for demographic and shared familial characteristics. Methods: We studied the relationship between current PTSD diagnosis and PA in 146 male twins (73 pairs) from the Emory Twin Study within the Vietnam Twin Registry. Twin pairs were discordant for PTSD symptoms. PA was continuously measured over 7 days using wrist actigraphy and used validated algorithms to calculate daily hours of sedentary time and moderate-to-vigorous PA (MVPA). We also examined self-reported leisure PA score with the Baecke questionnaire. We controlled for familial effect using generalized linear regression within PTSD discordant twin pairs. We dichotomized MVPA based on established cutpoints for normal values and estimated the prevalence ratio (PR) of the likelihood of achieving the minimum recommended average daily MVPA using Poisson regression. Multiple imputation was used to reduce the impact of missing data. Results: Veterans (mean (SD) age: 68.2 (2.1); 97% (142/146) White) had a low prevalence of achieving daily MVPA goals —35% among those with PTSD and 25% among those without and spent over 9 average sedentary hours per day. We did not find any significant relationship between current PTSD diagnosis and any of the PA outcomes in fully adjusted models. Discussion: Our findings reveal low PA and high levels of sedentary behavior among Veterans, with PTSD showing no significant impact on average PA. This suggests that PA is unlikely to explain excess CVD risks that have otherwise been observed in PTSD. Nonetheless, in this cohort of Vietnam era veterans, interventions to increase PA are warranted regardless of PTSD status.