To better understand the increased lifetime prevalence of PTSD and conditional risk of PTSD among the cocaine dependent cases recruited from treatment and the community-based cohort, further analyses were undertaken on predictors of PTSD. Figure 1 displays the percentage of all participants who met criteria for PTSD given the number of traumatic events experienced in their lifetime. There was a stepwise increase in the reporting of a diagnosis of PTSD as the number of traumatic events increase. Surprisingly, even after six and seven distinct traumas, the prevalence of PTSD did not plateau but rather continued to steadily increase. The elevated prevalence of PTSD in this sample may reflect the high number of different types of trauma that this population experienced. To further examine this, a logistic regression analysis was conducted using group status (cases or community-based cohort), gender, ethnicity, education, income, and number of traumatic events as predictors for conditional risk of PTSD. Gender and number of traumatic events were the only significant predictors of PTSD (female gender: OR=2.72, 95%CI: 1.79-4.13; number of traumas: OR=1.39, 95%CI: 1.28-1.50).
