Residual or re-emergent impaired insight into delusions following remission is unrelated to later relapse during a randomized clinical trial of continuation pharmacotherapy for psychotic depression - The STOP-PD II Study

Abstract

Background: Impaired insight into delusions is associated with a lower probability of remission of psychotic depression, independent of illness severity. The relationship between participant characteristics and impaired insight into delusions in remitted psychotic depression, and whether impaired insight is associated with risk of relapse of psychotic depression during continuation pharmacotherapy were examined.

Methods: Data were analyzed from 126 participants in the STOP-PD II study who experienced sustained remission of psychotic depression during 8-week stabilization treatment with sertraline plus olanzapine and were then randomized to 36 weeks of continuation treatment with sertraline plus either olanzapine or placebo. Insight into delusions was assessed with the Resolution of Delusions Scale (RODS). Linear regression analyses examined the associations between participant characteristics and insight into delusions. Cox proportional-hazards models examined whether i) change in RODS during stabilization treatment; or ii) RODS at the end of stabilization treatment predicted risk of relapse during 36 weeks of continuation treatment.

Results: Severity of psychosis before initiation of treatment was the only participant characteristic associated with the change in insight during stabilization treatment. Neither change in insight during stabilization treatment nor insight at the end of stabilization treatment was associated with risk of relapse.

Limitations: Insufficient statistical power and the lack of variability in RODS scores at the time of randomization may have contributed to the absence of a relationship between RODS and risk of relapse.

Conclusion: Residual or reemergent insight impairment following acute treatment does not preclude patients from sustaining remission of psychotic depression in a randomized placebo-controlled trial.

Keywords: Insight; Major depressive disorder with psychotic features; Pharmacotherapy; Psychotic depression; Randomized clinical trial.