A client presents with problems of anxiety. Most distressing to the client is his excessive worry about a number of things that he finds difficult to control and is negatively affecting his life. Using current classification systems like the DSM, we may initially conclude that this presentation can best be described as generalised anxiety disorder (GAD). We know there is a good evidence-base for psychological treatments for GAD and therefore, we have some confidence that our client’s anxiety may subside following the intervention. However, after further exploration we discover that the client is also extremely fearful of social interactions with strangers, is low in mood and has problems with sleep. What evidence base then can we draw from to confidently treat this particular client? In what order should we address his problems and why?
We know from clinical practice that this example is not unusual, in fact, it is extremely common! Clients often present with difficulties that meet the criteria for not one, but two or more anxiety disorders and other disorders like depression. Yet, most of the existing evidence base for psychological interventions for anxiety disorders is for treating people with single disorder presentations.
For this reason and more, during the past few decades there has been a growing movement towards ‘transdiagnostic research’. Part of this research has sought to investigate precipitating and maintaining psychological processes which operate across mental disorders (as defined by traditional diagnostic systems). In other words, what cognitive or behavioural processes may be common to many different mental health problems and are fundamental in how they become problematic and how they are maintained over time.
One such transdiagnostic process is repetitive negative thinking (RNT), which can be described as repeatedly thinking about one’s problems or experiences, which is perceived as uncontrollable and repetitive (Ehring & Watkins, 2008; Harvey et al., 2004). When we think about repetitive negative thinking in the context of anxiety disorders this mainly looks like worry i.e. repetitious, predominantly verbal thoughts anticipating and contemplating uncertain, negative outcomes of a problem.
Research has shown that although worry is mainly associated with GAD, it is also present in other disorders such as panic disorder, social anxiety disorder, sleep disorders and depression (to name a few!). So, in our example, the client’s excessive worry may also be relevant to his social anxiety, low mood and sleep problems. Then, if worry is present in all our client’s problems, did it play a role in how these problems started and how they are maintained? Again, research has shown that worry plays a part in both the development and maintenance of these disorders. We might then want to use an intervention that specifically targets the worry process, for which there are a number of therapeutic interventions.Examples include intolerance of uncertainty therapy, metacognitive therapy, mindfulness-based therapy, working memory training and behavioural activation for worry. The research evidence for these therapies is promising in that they seem to reduce both worry and the severity of the specific anxiety disorder. However, we still are unsure of whether interventions focusing on worry are better at reducing worry compared to other interventions and whether reducing worry is partly or wholly responsible for (i.e. mediates) anxiety reduction.
There has been a recent meta-analysis of treatment for depression which suggests that RNT-focused interventions have similar effects on reducing depression and RNT (namely, rumination) to traditional CBT interventions (Spinhoven et al., 2018). But interestingly, the reduction of RNT was associated with depression reduction in RNT-focused interventions but not traditional CBT interventions. This suggests that the improvements in depression symptomology after RNT-focused treatment may be mediated by reducing RNT. We do not know, however, whether this is also the case for RNT-focused treatments for anxiety disorders.
We therefore searched the literature of randomized controlled trials of anxiety treatments with control groups and reporting outcomes on both anxiety severity and RNT (i.e. worry, rumination or content-independent perseverative thinking). We found 46 studies which included RNT-focused and non-RNT-focused psychological treatments as well as non-psychological treatments for anxiety with a total of 3194 participants.
Our meta-analyses revealed that there were comparable, moderate effects on RNT and anxiety severity between RNT-focused and non-RNT-focused psychological treatments in favour of the active treatment group but heterogeneity was high. When we looked at the results after removing three outlier studies, the effects remained the same but the heterogeneity was reduced to moderate. We also found that changes in RNT and anxiety severity were highly associated across treatments. Unlike Spinhoven and colleague’s (2018) study, however, the association between reductions in RNT and anxiety was not specific to RNT-focused treatments. Although, a post-hoc analysis found that with the included studies in our analysis we had low power to detect differences in RNT between RNT-focused and non-RNT-focused psychological treatments.
Our results suggest that using a psychological (predominantly CBT-based) intervention may produce reductions in our client’s worry, whether it targets the RNT process or not. We postulate that other CBT techniques that aren’t specifically RNT-focused may indirectly influence the occurrence of RNT, hence why we found comparable effects between the two classes of treatment (RNT versus non-RNT). However, as the post-hoc power analysis suggests, we need more studies to substantiate these findings.
But what influences what? Although changes in RNT and anxiety severity were highly related we cannot say whether reductions in RNT result in decreasing anxiety severity, vice versa or if this relationship is bidirectional. Moreover, there could be other variables not accounted for which are influencing both e.g. general distress/negative affectivity. Strikingly, only one study included in the meta-analysis used a formal mediation analysis with more than two time points. We believe our findings call for high-quality, large-scale trials with multiple assessments appropriate for mediation analyses that can determine temporal precedence, as well as including relevant predictors and covariates. If it is found that targeting RNT is an essential element in treatment, we could more confidently treat many like our client who present with problems that cut across traditional diagnostic boundaries in anxiety disorders and beyond.
- Can we identify how the valence, purpose and process of repetitive negative thinking contribute to the development or exacerbation of anxiety and/or depressive disorders?
- How will emerging transdiagnostic research shape the way we classify and treat anxiety and other mental health problems?
Monteregge, S., Tsagkalidou, A., Cuijpers, P., & Spinhoven, P. The effects of different types of treatment for anxiety on repetitive negative thinking: A meta‐analysis. Clinical Psychology: Science and Practice, e12316.
Sabrina Monteregge received her MSc from Leiden University where she worked with Professor Philip Spinhoven and Anesteia Tsagkalidou during her research internship. She currently works as an assistant psychologist in the intensive care unit in Chelsea and Westminster Hospital, London.
Ehring, T., & Watkins, E. R. (2008). Repetitive negative thinking as a transdiagnostic process. International Journal of Cognitive Therapy, 1, 192-205. doi:10.1007/s10608-006-9089-7
Harvey, A. G., Watkins, E., Mansell, W., & Shafran, R. (2004). Cognitive behavioural processes across psychological disorders: A transdiagnostic approach to research and treatment. Oxford Oxford University Press, 365. doi:10.1002/erv.647
Spinhoven, P., Klein, N., Kennis, M., Cramer, A. O. J., Siegle, G., Cuijpers, P., . . . Bockting, L. (2018). The effects of cognitive-behavior therapy for depression on repetitive negative thinking: A meta-analysis. Behaviour Research and Therapy, 106, 71-85.doi:10.1016/j.brat.2018.04.002