People with bipolar disorder (BD) experience trauma at significantly higher rates than the general population, with estimates ranging from 50% to 80% having experienced a traumatic event at some point in their life (Assion et al., 2009; Maguire et al., 2008). Research has shown that trauma is associated with more severe illness outcomes, including earlier onset, increased symptom severity, higher comorbidity rates and more frequent mood episodes. (Hernandez et al., 2013).

While numerous reviews have explored the connection between childhood trauma and BD, there remains a lack of synthesis of research investigating trauma experience after childhood. Adulthood trauma, though less studied, is just as impactful, affecting between 62% and 90% of people with BD. Such trauma often results from disasters, crime, or assault (Maguire et al., 2008; Mowlds et al., 2010; Shannon et al., 2011).

Another crucial factor is cumulative trauma, which refers to the accumulation of multiple traumatic experiences over time. This can exacerbate psychological issues, including severe depression and heightened PTSD risk. Individuals with bipolar-I disorder typically report an average of 3.7 traumatic events during childhood (Kim et al. 2015), with 88% experiencing multiple traumas throughout their lives (O’Hare et al., 2013).

Most existing research has focused on identifying childhood trauma without delving into the extent or frequency of these traumatic experiences. To address this gap, the paper by Rowe et al., (2023) reviews past studies to explore how often individuals with bipolar disorder encounter multiple traumas and how these experiences affect their overall well-being.

Methods

A systematic review was carried out following the PRISMA guidelines to assess the prevalence and outcomes of cumulative trauma in Bipolar Disorder (BD). Researchers searched five databases- Embase, MEDLINE, PsycINFO, Web of Science, and PTSD Pubs—for studies published between January 2010 and December 2022.

To be included in the review, studies had to meet these criteria:

• Participants must have a formal BD diagnosis based on DSM or ICD criteria.
• Studies should use quantitative measures or screenings for different types of trauma, such as childhood trauma, domestic violence, and PTSD.
• The amount of trauma experienced had to be recorded, distinguishing between single and multiple occurrences.
• Articles needed to provide data on the prevalence of cumulative trauma and its associated outcomes.
• The studies had to be empirical, including randomised trials, observational studies, or experimental studies.
• If BD was combined with other diagnoses, separate analyses for BD were necessary.

The authors also assessed the Risk of Bias and Quality Appraisal using the Joanna Briggs Quality Appraisal Tools.

Results

20 articles were included in the review after screening. These studies included 9,304 participants with bipolar disorder (BD) from 13 countries. Most (95%) focused on adults aged 31.5 to 68.5 years, with one study on adolescents averaging 15.7 years. Two studies included only women, while 15 reported female representation from 41% to 72%.

The prevalence of cumulative trauma ranged from 29% to 82% and was associated with:

• Clinical characteristics of BD such as longer mood episodes, increased treatment types, more rapid cycling, postpartum depression, more lifetime depressive episodes and lower euthymia rates.
• Psychosis: Studies found mixed results on the relationship between cumulative trauma and psychosis; whilst two studies suggested a relationship, a further two studies found no evidence of a relationship.
• Suicidality: Three studies found a relationship between cumulative trauma and suicidality.
• Comorbid disorders: Three studies separately linked cumulative trauma to PTSD, substance use disorders, anxiety and lower psychosocial functioning.

Conclusions

Although research in this area is still emerging, this review uncovers some intriguing links between trauma and bipolar disorder (BD):

• It suggests that the more trauma someone experiences, the earlier they might develop BD, face longer mood episodes, and deal with more frequent mood swings.
• There is also a potential increase in the risk of psychosis and suicide attempts.

These findings highlight the importance for clinicians to dive deeper into their patients’ trauma histories and consider these risks when crafting treatment plans.

Strengths and limitations

This study offers a comprehensive and thorough review of existing research on cumulative trauma and its impact on bipolar disorder (BD). By analysing multiple studies, it presents a well-rounded understanding of the topic. One notable strength is its inclusion of a large sample size from various studies, which enhances the reliability and generalisability of the findings, allowing for broader implications. The focus on cumulative trauma helps illuminate how various traumatic experiences can influence the onset and severity of BD.

However, the review also highlights significant limitations. One major drawback is the scarcity of studies examining cumulative trauma specifically in adults. Only one study focused on adult trauma but did not provide prevalence data, leaving a gap in our understanding. Additionally, many studies collected relevant data but failed to analyse cumulative trauma specifically, making it difficult to distinguish between the impacts of experiencing a single traumatic event compared to multiple events. More research is necessary to clearly define cumulative trauma, as establishing a consistent definition in future studies will allow for a better understanding of its effects over a lifetime.

Implications for practice

There are several key implications for practice to consider. First, clinicians should prioritise gathering comprehensive trauma histories from their patients. Understanding the extent and nature of a patient’s traumatic experiences can help tailor treatment approaches and improve outcomes. Treatment plans should be individualised to address each patient’s specific trauma experiences, especially in terms of how cumulative trauma may affect mood episodes, symptom severity, and the risks of psychosis and suicidality.

Given the link between cumulative trauma and earlier onset of BD, implementing early intervention strategies for individuals with a history of trauma can be beneficial. Identifying at-risk individuals allows for timely support and symptom management. Additionally, adopting a trauma-informed care approach is crucial. Creating a safe environment, building trust, and empowering patients in their treatment decisions can greatly enhance therapeutic relationships. For more insights on trauma-informed care, please refer to my previous blog.

Mental health professionals should consider incorporating assessments for suicidality and psychosis risk, as understanding the links between cumulative trauma and these risks can enable timely intervention and support.

Statement of interests

The author of this blog works in a Complex Depression, Anxiety and Trauma service, where she often works with people with Bipolar Disorder and a history of severe trauma. There is no conflict of interest in relation to the research paper that this blog was based on.

Links

Primary paper

Rowe, A.-L., Perich, T., & Meade, T. (2024). Bipolar disorder and cumulative trauma: A systematic review of prevalence and illness outcomes. Journal of Clinical Psychology, 80, 692–713. https://doi.org/10.1002/jclp.23650

Other references

Assion, H.‐J., Brune, N., Schmidt, N., Aubel, T., Edel, M.‐A., Basilowski, M., Juckel, G., & Frommberger, U. (2009). Trauma exposure and post‐traumatic stress disorder in bipolar disorder. Social Psychiatry and Psychiatric Epidemiology, 44(12), 1041–1049. https://doi.org/10.1007/s00127-009-0029-1

Dualibe, A. L., & Osório, F. L. (2017). Bipolar disorder and early emotional trauma: A critical literature review on indicators of prevalence rates and clinical outcomes. Harvard Review of Psychiatry, 25(5), 198–208. https://doi.org/10.1097/HRP.0000000000000154

Hernandez, J. M., Cordova, M. J., Ruzek, J., Reiser, R., Gwizdowski, I. S., Suppes, T., & Ostacher, M. J. (2013). Presentation and prevalence of PTSD in a bipolar disorder population: A STEP‐BD examination. Journal of Affective Disorders, 150(2), 450–455. https://doi.org/10.1016/j.jad.2013.04.038

Maguire, C., McCusker, C. G., Meenagh, C., Mulholland, C., & Shannon, C. (2008). Effects of trauma on bipolar disorder: The mediational role of interpersonal difficulties and alcohol dependence. Bipolar Disorders, 10(2), 293–302. https://doi.org/10.1111/j.1399-5618.2007.00504.x

Mowlds, W., Shannon, C., McCusker, C. G., Meenagh, C., Robinson, D., Wilson, A., & Mulholland, C. (2010). Autobiographical memory specificity, depression, and trauma in bipolar disorder. British Journal of Clinical Psychology, 49(2), 217–233. https://doi.org/10.1348/014466509X454868

Shannon, C., Maguire, C., Anderson, J., Meenagh, C., & Mulholland, C. (2011). Enquiring about traumatic experiences in bipolar disorder: A case note and self‐report comparison. Journal of Affective Disorders, 133(1–2), 352–355. https://doi.org/10.1016/j.jad.2011.04.022

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