Optimizing Extinction Using Intensified Psychological Interventions for Adult Anxiety Disorders (AD)

To examine the efficacy of intensified psychological interventions (IPI) aiming to augment extinction learning during exposure. In IPI we increase the number of exposure trials and decrease the spacing between sessions providing more “extinction trials” over a shorter duration. To stabilize treatment effects we provide spaced exposure training during follow-up (booster) in different contexts. We also based exposure on a positive prediction error model. We hypothesize that IPI results in stronger, faster and more pervasive effects in subjective, behavioural, physiological, neural and epigenetic indices at post and follow-up via optimizing extinction learning. To test the hypothesis, we propose a multicentre randomized clinical trial (RCT). Patients will be randomly allocated to either IPI or standard research exposure treatment as usual (TAU) as the control condition. Primary hypotheses: (1) IPI will be superior to TAU at post and follow-up on primary and secondary outcome measures and will recover faster. Secondary hypotheses are: (2) IPI is associated with enhanced positive prediction error to increase extinction learning during and after exposure and (3) will result in more pronounced changes in behavioural proxy measures (between session reduction of fear, anxiety, avoidance) of extinction learning. We also explore the effect of type of diagnosis and comorbidity as potential moderators of outcome and extinction. We further expect that IPI will be associated with lower direct and indirect health care costs.