From brooding to detachment: Rumination longitudinally predicts an increase in depersonalization and derealisation.

OBJECTIVES

Depersonalization-derealization (DEP-DER) is a dissociative experience which is related to psychopathology and distress. Yet, the aetiological factors leading to DEP-DER are not sufficiently clear. In this study, we suggest rumination as one possible antecedent. Thus, the goal of the study was to explore the longitudinal relationship between rumination and DEP-DER.

DESIGN

Longitudinal self-report study; mixed clinical and community sample.

METHODS

The study was conducted on 98 participants, 49 of them were diagnosed with depression, anxiety disorders, or obsessive-compulsive disorder, and the other 49 were healthy, matched community controls. The participants underwent a structured clinical interview and completed a battery of questionnaires. Then, the participants completed the same battery again once a month, for five additional assessment points (6 months in total). The data were analysed using multilevel linear modelling with time-lag analysis.

RESULTS

We found that levels of rumination and DEP-DER increased and decreased simultaneously, meaning that on assessments in which people reported that they tended to ruminate, they also reported higher levels of DEP-DER symptoms. In addition, we found support for a unidirectional association, consistent with our theoretical hypothesis. Specifically, rumination levels on a certain month longitudinally predicted a higher likeliness for reporting DEP-DER on the following month, even when controlling for the contemporaneous relationship. Conversely, DEP-DER symptoms did not longitudinally predict increased rumination.

CONCLUSIONS

These findings suggest that rumination may be an antecedent of DEP-DER, but not vice versa. Possible mechanisms to explain this link are discussed.

PRACTITIONER POINTS

Rumination and DEP-DER oscillate together over time; additionally, rumination predicts a longitudinal increase in DEP-DER. Clinicians noticing ruminative thought followed by decreased emotionality should distinguish between an authentic decrease of distress versus detachment. The findings provide one possible explanation for the frequency of DEP-DER symptoms in anxiety and depressive disorders. Poor sleep quality and emotion regulation difficulties should be explored as potential mediators explaining this link.