Effects of personalized depression prevention on anxiety through 18-month follow-up: A randomized controlled trial.

Depression and anxiety frequently co-occur and share several risk factors. There is some evidence for transdiagnostic effects of prevention programs on depression and anxiety. In the Personalized Depression Prevention (PDP) study, youth (n = 98, Mage = 13.94 years, SD = 1.67) were classified as high or low on cognitive and interpersonal risk factors and randomized to either a cognitive-behavioral or an interpersonal prevention program. Some participants received a match between risk and prevention, others received a mismatch. Our initial work found evidence for the benefits of personalization on depression outcomes. In this paper, we focus on secondary anxiety outcomes through 18-months post-intervention. We found evidence for the benefits of personalized prevention on anxiety symptoms during the 18-month follow-up period, but not during the intervention. From post-intervention to 18-month follow-up matched youth showed a decrease in anxiety symptoms whereas mismatched youth showed a significant increase in symptoms (d = 0.87, p = .001). The rates of anxiety disorders were equivalent across the groups (p = 1.00). Given the comorbidity of depression and anxiety, interventions that have effects on both may be an efficient and cost-effective approach to reducing the burden associated with these conditions. A risk-informed personalization approach to prevention may be one way to enhance the transdiagnostic effects of depression prevention.