Intranasal oxytocin may reduce irritability in youths with mood disorders

Treatment with intranasal oxytocin appears to produce neural-level changes in emotion processing among young people with irritability caused by disruptive behaviour disorders (DBDs) or disruptive mood dysregulation disorder (DMDD), suggests a study.

A team of researchers randomized 52 participants with severe irritability, as measured by a score ≥4 on the Affective Reactivity Index (ARI), who had been diagnosed with DBD or DMDD to receive either intranasal oxytocin or placebo daily for 3 weeks. They assessed the outcomes at baseline and at the end of the trial.

Measures of irritability on the ARI and ratings on the Clinical Global Impressions severity scale (CGI-S) focusing on DBD and DMDD symptoms were the primary outcomes. Secondary outcomes consisted of the CGI improvement scale (CGI-I) and ratings of proactive and reactive aggressive behaviour on the Reactive-Proactive Aggression Questionnaire.

Of the participants, 43 (22 in the oxytocin group and 21 in the placebo group) completed pre- and post-treatment functional magnetic resonance imaging (fMRI) scans with the affective Stroop task.

Participants in the oxytocin group had significantly improved CGI-S and CGI-I ratings compared with those in the placebo group.

Data from fMRI scans revealed significantly reduced blood-oxygen-level-dependent (BOLD) responses to emotional stimuli in the dorsomedial prefrontal cortex and posterior cingulate cortex after oxytocin treatment relative to placebo. Notably, the BOLD response changes contributed to improvements in clinical severity.

“This study provides initial and preliminary evidence that intranasal oxytocin may induce neural-level changes in emotion processing in youths with irritability in the context of DBDs and DMDD,” the researchers said. “This may lead to symptom and severity changes in irritability.”