6 - (IOP 17) Generalized Anxiety and Intolerance of Uncertainty in Everyday Life Among High-neuroticism Adults

Generalized anxiety disorder (GAD)—characterized by excessive and difficult-to-control worry—is a prevalent mental health concern. Theoretical models of GAD implicate cognitive factors in its onset and maintenance such as intolerance of uncertainty (IU), defined as experiencing distress in response to uncertain or ambiguous situations, or viewing such events as unacceptable. In particular, the Intolerance of Uncertainty Model of GAD (Dugas et al., 1998) considers IU a central risk factor that may exacerbate initial worry. Further, there is strong evidence that people who are high in IU are generally vulnerable to worry. However, how IU and GAD symptoms co-occur on a within-person level is unclear. Testing the extent to which daily change in one covaries with daily change in the other is clinically relevant because theoretical models are naturally conceptualized at the within-person level, and can extend our understanding of these associations beyond simply who tends to be at high risk for GAD, and onto when and in what context someone is at greatest risk. The current study used a daily diary design to explore how IU and GAD symptoms are associated on a within-person level. Given that high neuroticism is broadly linked to GAD and other anxiety disorders (Barlow et al., 2014), to increase our findings’ relevance to clinical populations, we recruited a sample of 209 high-neuroticism young adults (M = 19.0 years, 56.9% female, 56.5% white, 69.4% heterosexual; 38.8% self-reported an anxiety disorder diagnosis). Participants completed a baseline survey assessing trait IU and GAD symptoms, then reported state-like IU and GAD symptoms daily for 14 consecutive days. As expected, IU and GAD symptoms were moderately to strongly correlated at the between-person level when measuring baseline scores (r = .41, p < .001) and aggregated daily diary scores (r = .63, p < .001). Intraclass correlations indicated that 36% of the variance in IU scores and 51% of the variance in GAD scores were attributable to within-person differences over the study period. In other words, both fluctuated considerably within individuals over time rather than being entirely stable traits. Our primary result was a significant within-person correlation between same-day IU and GAD symptoms (r = .43, p < .001). We also tested the prospective within-person effects of IU on next-day GAD symptoms, controlling for lagged symptoms, and did not find a significant effect (β = 0.04, SE = 0.03, p = .161). These analyses confirm that IU and GAD are intimately intertwined not just on a between-person level, but also within-person. The observed within-person correlation is notably large for a within-person context, underscoring the strong relationship between these variables. Findings are consistent with the idea that challenging clients’ beliefs about uncertainty in cognitive behavioral therapy (Robichaud, 2013) could reduce worry relative to a patient’s norm, but intensive longitudinal measurement within a therapy context is needed to directly test this idea. Limitations include a non-clinical sample, though studying high-neuroticism adults suggests findings may generalize to clinical populations. In sum, this study supports IU as a dynamic construct and potential treatment target for GAD.