This study yields additional evidence for the increased risk of PTSD associated with drug dependence. Other investigators have noted rates of lifetime PTSD among substance abusers ranging from 20% to 52% (Back et al., 2000; Johnson et al., 2006; Reynolds et al., 2005; Wasserman et al., 1997). Our current study shows 24% of the individuals recruited from treatment with cocaine dependence who experienced a traumatic event met criteria for PTSD. This high prevalence is a function of the number and violent nature of traumatic events experienced by these individuals. Najavits and colleagues (1998) reported individuals with PTSD endorsing significantly more traumatic experiences than those without PTSD and our study confirms this finding. Further, evidence suggests that experiencing assaultive violence such as being raped, stabbed, or shot, is associated with higher rates of PTSD (Breslau et al., 2004; Hapke et al., 2006). Thus, the cumulative violent experiences of cocaine dependent cases are likely contributing to a higher prevalence of PTSD and possibly other psychological disorders. This has important treatment implications for treating those with comorbid PTSD and substance dependence. In addition
