Risk factors associated with posttraumatic stress disorder in US veterans: A cohort study

OBJECTIVE To assess the association between clinical and exercise test factors and the development of posttraumatic stress disorder (PTSD) in US Veterans. PATIENTS AND METHODS Exercise capacity, demographics and clinical variables were assessed in 5826 veterans (mean age 59.4 ± 11.5 years) from the Veterans Affairs Healthcare System in Palo Alto, CA. The study participants underwent routine clinical exercise testing between the years 1987 and 2011. The study end point was the development of PTSD. RESULTS A total of 723 (12.9%) veterans were diagnosed with PTSD after a mean follow-up of 9.6 ± 5.6 years. Drug abuse (HR: 1.98, CI: 1.33-2.92, p = .001), current smoking (HR: 1.57, CI: 1.35-2.24, p <.001), alcohol abuse (HR: 1.58, CI: 1.12-2.24, p = .009), history of chest pain (HR: 1.48, CI: 1.25-1.75, p <.001) and higher exercise capacity (HR: 1.03, CI: 1.01-1.05, p = .003) were strong independent risk factors for PTSD in a univariate model. Physical activity pattern was not associated with PTSD in either the univariate or multivariate models. In the final multivariate model, current smoking (HR: 1.30, CI: 1.10-1.53, p = .002) history of chest pain (HR: 1.37, CI: 1.15-1.63, p <.001) and younger age (HR: 0.97, CI: 0.97-0.98, p <.001) were significantly associated to PTSD. CONCLUSIONS Onset of PTSD is significantly associated with current smoking, history of chest pain and younger age. Screening veterans with multiple risk factors for symptoms of PTSD should therefore be taken into account.