Internalized mental disorders, such as anxiety and depression, are among the most common mental illnesses during adolescence. Recently, a large-scale longitudinal cohort study found that internalized mental disorders in adolescents have two subtypes: hyperimpulsivity and hypoimpulsivity. The hyperimpulsivity subtype had a higher conversion rate to externalized mental disorders, higher levels of depression, and a higher risk of suicide than the hypoimpulsivity subtype. The related paper was recently published in the international journal *British Journal of Psychiatry*.
The research team first used five dimensions of the Impulsive Behavior Scale-negative urgency, positive urgency, lack of perseverance, lack of planning, and pleasure seeking-to conduct a cluster analysis on 2,430 adolescent patients, identifying two subtypes with the same anxiety level but opposite impulse levels: the high-impulsivity subtype and the low-impulsivity subtype.
The study found that the two subtypes had opposite anxiety-impulsivity relationships: the baseline anxiety level of the high-impulsivity subtype was positively correlated with baseline and two-year follow-up impulsivity (lack of perseverance) levels, while the baseline anxiety level of the low-impulsivity subtype was negatively correlated with baseline and two-year follow-up impulsivity (pleasure seeking) levels. This finding suggests that different subtypes adopt different anxiety coping strategies: the high-impulsivity subtype employs maladaptive coping strategies, namely, obtaining immediate gratification through impulsive behavior to alleviate anxiety; while the low-impulsivity subtype chooses adaptive coping strategies, namely, addressing the anxiety-causing problem by reducing sensitivity to external disturbances.
Considering that different subtypes may adopt different coping strategies when faced with anxiety, leading to subsequent changes in future mental health, the research team explored the differences in the development of psychopathological symptoms and cognitive abilities between the two subtypes during follow-up. The follow-up revealed that the high-impulsivity subtype had a higher rate of externalized mental disorder conversion, higher levels of depression, lower suicide risk, and poorer cognitive and academic performance than the low-impulsivity subtype. These findings are significant for the timely identification of high-impulsivity internalized mental disorder subtypes and for providing individualized and precise interventions for patients with mood and behavioral disorders.
