Traditional diagnostic approaches to psychopathologies, like those found in the DSMs, have focused on differences between disorders and resulted in an excessive number of therapies that are applicable to just a tiny percentage of the population. Transdiagnostic strategies on the other hand, take the opposite approach by emphasizing the similarities between groups to develop treatments that are useful to a wider range of people with mental health afflictions.
A 2016 study published in Clinical Psychological Science utilized transdiagnostic theory to reveal that rumination, the act of obsessing on negative experiences, is correlated with a host of psychological conditions.
The experiment, conducted by Daniel Johnson and colleagues, collected data from 744 participants (365 pairs of twins plus some singletons without their twin) using a self-reported survey. Twin study designs like this one have the advantage of providing a way to measure genetic influence. The surveys were designed to obtain values for rumination, self-reflection, depressive symptoms, eating pathology and psychiatric diagnoses. Self-reflection was included to control for its association with rumination. Depressive symptoms and eating pathology measurements were not based on official clinical diagnostic guidelines and did not require an existing diagnosis to be considered applicable.
A complicated series of statistical analyses showed that rumination is indeed associated with all three included measures of psychopathology (depressive symptoms, eating dysfunction and diagnosis), and that the relationship is not dependent upon self-reflection. Correlations between twins demonstrated that all of these associations had a significant genetic component, though none were so complete as to exclude environmental factors. The most significant genetic influence was evident between rumination and depression, with the eating pathology association moderately impacted by genetics and the rumination-substance dependence link appearing to be mostly environmental in origin.
The results of this study have several important implications. Primarily, they present examples of how the transdiagnostic approach can be used to effectively identify and examine relationships between psychopathologies and variables in ways that would not be possible using the traditional diagnostic method.
“Our results support the conceptualization of rumination as a pattern of repetitive, self-directed thought that is a unique and specific risk factor for several forms of pathology,” Johnson and colleagues wrote in their study.
Rumination was shown to have a significant association with several characteristics from across a range of psychopathologies. By including a genetic aspect to the analysis, the researchers were also able to demonstrate that the ratio of contributions to these associations by genetic and environmental factors can differ depending on the exact variables being measured (such as across diagnosis types).
“As the first behavior genetic study to examine rumination as a transdiagnostic correlate of psychopathology, this study provides a strong foundation for exploring new avenues of research that could guide prevention and treatment efforts in individuals suffering from comorbid psychiatric disorders,” the researchers concluded.