A Systematic Review of Trials Targeting Depression and Anxiety in Patients With Delusions

Abstract

Abstract. Negative affect and impaired emotion regulation skills are prevalent in patients with delusions and contribute to delusion formation and maintenance. This review evaluates existing research on interventions targeting negative affect and emotional processes as a causal mechanism on the pathway to delusions. A MEDLINE and PsycINFO search identified 7,909 articles. Five studies with randomized-controlled designs and three with uncontrolled designs met the inclusion criteria. Interventions comprised cognitive-behavioral and compassion-focused techniques. Overall, the review studies found positive intervention effects on negative affect and delusions. Where significant, controlled effect sizes ranged from small to large for negative affect and from moderate to large for delusions. Thus, existing research indicates that negative affect in patients with delusions can be modified by psychological therapy and points toward a carryover effect from the reduction of negative affect to a reduction of delusions. More large-scale randomized-controlled studies are needed to be able to draw valid conclusions on which types of interventions are most beneficial.