From anxiety to depression: A longitudinal investigation into the role of anhedonia.

Anxiety and depression are highly comorbid with each other, warranting a need to better understand transdiagnostic mechanisms. Anhedonia has been hypothesized as a transdiagnostic mechanism but has often been investigated as a unidimensional factor. Thus, the current study examined how anticipatory and consummatory anhedonia, including how they interact with anxiety, predict next-week depression. Participants (N = 101) completed weekly assessments of anxiety, depression, and anhedonia. Using an iterative approach, we constructed four models to investigate independent and interactive effects of prior-week anxiety and anhedonia on next-week depression, as well as the effects of depression and anhedonia on anxiety. Our results indicate that anticipatory anhedonia is associated with next-week depression, and the association between anxiety and depression is greater when anticipatory anhedonia is high. The current findings provide insight into the transdiagnostic nature of anticipatory anhedonia between anxiety and depression. Future work should investigate how these associations may unfold over shorter time periods.