Irritability and mood symptoms in adolescent girls: Trait anxiety and emotion dysregulation as mediators.

Background: Irritability is a common symptom in youth that is thought to be predictive of mood disorders. Its effects on mood are likely to be age-dependent, with direct and indirect mediators. We assessed age-related effects and mediators of irritability in adolescent girls with subthreshold depressive and manic symptoms.

Methods: We analysed the irritability item from the Mood Disorder Questionnaire in 3 cohorts of girls aged 12-18years (N=229); 12-13years (N=82); 14-15years (N=68); and 16-18years (N=79). They also completed mood, anxiety and emotion regulation questionnaires. MANOVA, correlations and bootstrapped mediation analyses were performed with SPSS®v25 and Hayes Processv3.5®.

Results: Overall, irritable girls had higher depressive and manic symptoms, trait anxiety and emotion dysregulation than those who were not irritable. Significantly higher rates of irritability were observed in mid-adolescents (aged 14-15years; p = 0.001). Notably, irritability exerted effects on depressive symptoms via trait anxiety, non-acceptance of emotions and dysregulation in emotion clarity throughout adolescence. However, irritability directly exerted effects on manic symptoms in mid-adolescence but in older adolescents, their relationship was indirect via impulse control dysregulation.

Limitations: The cross-sectional design and non-clinical sample limit generalisability of our findings.

Conclusions: Irritability is involved in subthreshold depressive symptoms, via trait anxiety and perceptual emotion dysregulation. On the other hand, irritability is directly and indirectly associated with subthreshold manic symptoms via dysregulated impulse control depending on age. Therefore, screening for irritability, trait anxiety and emotion dysregulation throughout adolescence may facilitate the early detection of subthreshold depressive and manic symptoms, and the implementation of preventive strategies.