Anticipatory anxiety in phobic postural vertigo patients – functional indicators for anxiety-related disorder

Patients with phobic postural vertigo (PPV) show symptoms similar to anxiety disorders. Anticipatory anxiety (AA) is a very common phenomena in those disorders. The aim of this study was the investigation of AA-associated functional responses in PPV patients compared to healthy controls (HC). For that purpose in fMRI, AA was provoked in participants due to anticipation of the cholecystokinin-tetrapeptide (CCK-4) injection, which is known to induce panic attacks. 15 PPV patients and 15 gender and age matched HC underwent the challenge. Participants did not know the exact time point of the injection in order to separate the anticipatory and CCK-4 induced anxiety. Additionally psychiatric and somatic symptoms were assessed. Healthy controls showed functional responses mainly in fronto-temporal regions. PPV patients revealed pronounced BOLD responses e. g. in the Insula, Amygdala, anterior cingulate cortex, gyrus temporalis superior and cuneus. Subjective ratings indicated that AA was associated with increased anxiety in patients than in HC. Furthermore significantly increased depression scores were demonstrated in patients. In PPV patients anticipatory anxiety led to pronounced BOLD responses in brain regions which play a central role in anxiety and cognition in fear-related processes. These neuronal responses were more pronounced than in healthy subjects. Given this fact these findings could provide evidence for common aspects of phobic postural vertigo and anxiety disorders.