You are working with a patient who struggles with intense emotions, unstable relationships, and a long history of difficult life experiences. You suspect that trauma may play a role, but they don’t really meet the criteria for post-traumatic stress disorder (PTSD). So, what should you do? Should you still treat the trauma or just focus solely on the ‘personality disorder’?
Individuals who are diagnosed with ‘personality disorder’ (PD) often report high levels of unpleasant experiences, such as emotional abuse, neglect, and other distressing experiences. Research suggests that up to 73% report abuse and over 80% report neglect (Hafkemeijer et al., 2025). Despite this prevalence, trauma-focused therapies are not usually offered to this population, partly since PTSD is likely to be underdiagnosed or masked by the complex PD symptoms (Hofman & Slotema, 2024).
Eye Movement Desensitisation and Reprocessing (EMDR) is an evidence-based therapy for PTSD and well-established (Torres-Gimenez et al., 2024). However, little is known about whether EMDR can help individuals with PD, particularly those who do not meet the PTSD diagnostic criteria, but still experience distress linked to past experiences (Hafkemeijer et al., 2024).
A randomised controlled trial by Hafkemeijer et al. (2025) tried to answer the question: Can EDMR reduce trauma-related symptoms in people with ‘personality disorder’, regardless of whether they have a formal PTSD diagnosis? By doing this, it challenges us to rethink how broadly trauma-focused therapies might be applied in clinical practice.
People with ‘personality disorder’ report high levels of adverse life experiences.
Methods
This trial was a single-blind, multicentre randomised controlled trial comparing Eye Movement Desensitisation and Reprocessing therapy with a waitlist control. Adults diagnosed with PD were recruited from outpatient mental health services in the Netherlands and randomly allocated to either receive EMDR or remain on a waitlist.
Participants in the EMDR group received ten 90-minute sessions over a span of 5 weeks, focusing on processing distressing memories linked to current symptoms. The symptoms of PTSD and the diagnosis were assessed using the Clinician-Administered PTSD Scale (CAPS-5) at baseline, post-treatment, and at a three-month follow-up. Most importantly, the study included participants with and without a formal diagnosis of PTSD, which allowed the researchers to explore whether EMDR can be effective beyond traditional diagnostic boundaries.
Results
A total of 159 participants were recruited for this trial, with 79 allocated to EMDR and 80 to the waitlist control. Both groups were compared at baseline, with no significant differences in demographic or clinical characteristics.
Overall, EMDR therapy resulted in greater reductions in PTSD symptoms over time compared to the waitlist. These improvements were demonstrated both immediately after treatment and at the three-month follow-up, which indicates that the benefits were not only significant but also sustained. In practical terms, this means that participants who received EMDR therapy experienced a decrease in trauma-related distress compared to those who did not receive active treatment.
Among participants who met PTSD criteria at the start of this study, effect sizes were large after treatment (Cohen’s d = 1.26, compared to d = 0.28 in the waitlist group), and grew further at three months (d = 1.5). To give that some context, a Cohen’s d above 0.8 is conventionally considered a large effect, so these figures sit well above that threshold.
Most important, 65.5% of those in the EMDR group no longer met criteria for PTSD after treatment, and at the follow-up, it increased to 73.1%. In contrast, fewer participants in the waitlist group demonstrated this level of recovery over the same time period.
Interestingly, EMDR was also effective for participants who did not have a formal PTSD diagnosis. In this group of participants, moderate to large reductions in PTSD symptoms were observed (d = 0.77 after treatment, rising to d = 1.09 at follow-up), which suggests the EMDR can help address trauma-related distress, even when it does not meet the diagnostic thresholds.
The trial also explored the types of memories targeted in therapy. Quite a few participants worked on experiences, including emotional abuse and neglect, which do not always meet Criterion A for PTSD. EMDR led to significant symptom decreases across different types of adverse memories, with no clear differences between them. This suggests that EMDR can be applicable to a range of distressing life experiences, and not just traditionally defined trauma.
This trial suggests that EMDR can help reduce trauma-related symptoms in people with a personality disorder diagnosis.
Conclusions
The study suggests that EMDR therapy can reduce PTSD symptoms in people with personality disorders. Interestingly, these effects were observed both in individuals with a formal PTSD diagnosis and in those without, highlighting the potential value of trauma-focused therapy beyond traditional diagnostic boundaries.
The researchers concluded that EMDR can be effective in targeting a wide range of distressing memories, including those that do not usually meet the PTSD criteria, and could play a meaningful role in improving outcomes for this population.
This research suggests that EMDR can be effective in targeting a wide range of distressing memories, including in those who that do not meet PTSD criteria.
Strengths and limitations
This study has a few notable strengths. Firstly, the use of a randomised controlled trial design strengthens the findingsas it reduces the risk of selection bias and allows for clear comparisons between EMDR and the control conditions. The recruitment from outpatient services also improves the clinical relevance of this study; this means that the findings are likely to reflect real-world practice. Additionally, including individuals with and without a PTSD diagnosis is a strengthas it addresses an essential gap in literature.
The study used well-known and reliable toolssuch as the CAPS-5 for PTSD and structured interviews for PD, supporting the validity of the outcome measures. The follow-up at 3 months showed that the treatment effects were maintained over time, which strengthens the study as well.
The study has several limitationswhich need to be considered. For example, a waitlist control was usedrather than an active comparable treatment, so this trial doesn’t tell us whether EMDR is more effective than other therapy types. This means that improvements could reflect non-specific factors like getting attention from therapists or participant expectations, rather than the active ingredient of EMDR.
Additionally, the study had higher dropout and missing outcome data in the control groupespecially participants with severe symptoms. This implies potential for bias and overestimation of the effectiveness of EMDR. Therefore, the findings should be cautiously interpreted.
This study mainly focused on PTSD symptoms, this means it limits the understanding of the impact of EMDR on other factors of personality disorder, such as interpersonal functioning or emotional regulation. Therefore, future research would benefit from further studies that include these.
The study has strengths but important questions remain.
Implications for practice
This study has important implications for how we might think about trauma in individuals with ‘personality disorder’. In the clinical world, trauma is often included in the patient’s history, but not always targeted in treatment, especially if the patient does not meet the criteria for PTSD. The findings of this study imply that this may need some reconsideration.
EMDR can reduce trauma-related symptoms, even without a full PTSD diagnosis, challenging the assumption that trauma-focused therapies should only be for diagnosed patients, because many people with PD show trauma symptoms linked to adverse experiences such as emotional abuse or neglect. This suggests that such experiences are still important and should be addressed in treatment.
For professionals, this means that it is important to assess trauma thoroughly. Symptoms like emotional dysregulation or interpersonal difficulties can be rooted in unresolved adverse experiences. EMDR could potentially be a useful addition to existing treatments for personality disorders.
This study makes you think about whether past experiences are continuing to shape present difficulties and if so, can trauma-focused therapies play a role in treatment.
Statement of interests
Vivien Ciftci has no conflicts to declare. AI tools were used to assist with proofreading and structuring.
Edited by
Edited by Simon Bradstreet.
Links
Primary paper
Hafkemeijer, L., Hofman, S., de Jongh, A., et al. (2025). The Effectiveness of Eye Movement Desensitization and Reprocessing Therapy on Post-Traumatic Stress Disorder Symptoms and Diagnostic Status in Patients with a Personality Disorder: A Randomized Controlled Trial. Psychother Psychosom, 94453-465.
Other references
Hafkemeijer, L., de Jongh, A., Starrenburg, A., Hoekstra, T., & Slotema, K. (2024). EMDR treatment in patients with personality disorders. should we fear symptom exacerbation? European Journal of Psychotraumatology, 15(1).
Hofman, S., & Slotema, C. W. (2024). Underdiagnosis of posttraumatic stress disorder among outpatients with personality disorders in clinical practice despite the use of a diagnostic instrument. Journal of Personality Disorders, 38(5), 477–492.
Torres-Giménez, A., Garcia-Gibert, C., Gelabert, E., Mallorquí, A., Segu, X., Roca-Lecumberri, A., Martínez, A., Giménez, Y., & Sureda, B. (2024). Efficacy of EMDR for early intervention after a traumatic event: A systematic review and meta-analysis. Journal of Psychiatric Research, 17473–83.
