DSM-5 BPD and ICD-11 complex PTSD: Co-occurrence and associated factors among treatment seekers in Hong Kong

There is an ongoing debate regarding whether ICD-11 complex PTSD and DSM-5 borderline personality disorder (BPD) are the same syndrome. Little is known about the extent to which these two conditions overlap and whether they exhibit distinct clinical correlates in Asian cultures. This study examined the co-occurrence of ICD-11 complex PTSD and DSM-5 BPD in a sample of treatment seekers in Hong Kong (N = 220). Participants completed validated self-report measures which assessed if they met the respective diagnostic criteria. In this sample, 30.9 % met the ICD-11 criteria for complex PTSD only, 10.0 % met the DSM-5 criteria for BPD only, and 28.2 % met the criteria for both conditions. Complex PTSD symptoms were most strongly associated with depressive symptoms (β =.347, p <.001) and trauma-related maladaptive beliefs (β =.337, p <.001), while BPD symptoms were most strongly associated with dissociative symptoms (β =.281, p <.001). This study is the first to show that ICD-11 complex PTSD and DSM-5 BPD commonly co-occurred but were not the same construct in the Asian context, and their symptoms were associated with different sets of demographic and clinical factors. Future editions of DSM and ICD should not merge the two conditions into a single diagnosis.