Exploring mood symptoms overlap in PTSD diagnosis: ICD-11 and DSM-5 criteria compared in a sample of subjects with Bipolar Disorder

Background: The latest edition of the ICD (ICD-11) introduced relevant modifications to Post-traumatic Stress Disorder (PTSD) diagnostic criteria with respect to those of the DSM-5, including the exclusion of DSM-5 symptoms that potentially overlapped with mood disorders. To date, no study has yet investigated the differences in PTSD and its related symptoms, according to the two diagnostic systems in subjects with mood disorders. The aim of the present study was to compare the DSM-5 and ICD-11 diagnostic criteria for PTSD in a sample of patients with Bipolar Disorder (BD). Methods: An overall sample of 210 in-patients with BD completed the Trauma and Loss Spectrum-Self Report, assessing post-traumatic stress symptoms, to compare symptomatological PTSD diagnosis according to either the DSM-5 or the ICD-11 criteria. Results: DSM-5 PTSD was detected in 41% of the whole sample, whereas ICD-11 PTSD in 31.8%. The two diagnostic systems showed good concordance (Cohen's k = 0.643), whereas the concordance of re-experiencing and arousal criteria were moderate (Cohen's k = 0.578) and good (Cohen's k = 0.791), respectively. Almost all the subjects with a diagnosis of ICD-11 PTSD (92.5%) endorsed the “negative alterations in cognitions and mood” DSM-5 criterion. Limitations: The small size, the use of a self-report instrument. Conclusion: Our findings show high rates of PTSD and post-traumatic stress symptoms among subjects with BD according to both DSM-5 and ICD-11 criteria, despite significantly lower with the latter. However, potentially DSM-5 mood overlapping symptoms appear to be significantly higher among bipolar patients with ICD-11 PTSD with respect to those without.