In a large, nationally representative sample, the lifetime prevalence of PTSD only, AD only, and PSTD-AD were 6.42%, 15.25% and 1.59%, respectively. Compared with individuals with PTSD only, individuals with PTSD-AD were more likely to be never married, have no insurance, have a history of childhood adversities, and endorse familial risk factors. They also had more severe forms of PTSD, as indicated by greater number of diagnostic criteria met, higher likelihood of using substances to relieve PTSD symptoms, and higher rates of other lifetime psychiatric comorbidity. Moreover, although individuals with PTSD-AD had greater number of AD diagnostic criteria and poorer physical and psychosocial functioning than those with AD only, they were not more likely to seeking treatment for AD. Furthermore, rates of 12-month treatment for PTSD and AD among individuals with PTSD-AD were very low.
