Title: Patterns of Symptom Improvement among Depressed Adolescents treated with Interpersonal Psychotherapy Adolescent Skills Training (IPT-AST) in School Based Clinics
Description: Subthreshold symptoms of depression (defined as symptoms that do not meet full criteria for the disorder) are a significant concern, associated with a range of behavioral and emotional problems, raising the risk of adolescents developing more severe depression later. Yet research on subthreshold depression is lacking, and the relationship between affective and somatic symptom improvement has not been adequately studied. Prior research with adult samples lend credence to the hypothesis that symptoms of mood/motivation respond faster to psychotherapy (Rush, Beck, Kovacs, Weissenburger, and Hollon, 1982) than pharmacotherapy with the opposite response for vegetative symptoms such as sleep and appetite (DiMascio, Weissman, Prusoff, and Neu 1979). The current study was built upon prior research that found Interpersonal Psychotherapy Adolescent Skills Training (IPT-AST) to be an efficacious prevention intervention for adolescents with subthreshold depression, as compared to school counseling (Young, Mufson and Gallop, 2010).

In this investigation, we sought to compare the trends in symptomatic improvement among 32 participants treated with IPT-AST over eight weeks. Clusters of mood/ motivation and vegetative symptoms were followed from baseline to the end of treatment. The results suggest that mood symptoms improved significantly before vegetative symptoms, within the first four weeks of preventive treatment. Significant improvement in vegetative symptoms was found to occur later between weeks 6 and 8. Thus adolescents receiving IPT-AST preventive treatment demonstrated faster reduction in mood/motivation symptoms than vegetative symptoms. Analyses revealed that fewer participants were identified as having not improved on the mood/motivation cluster than on the vegetative cluster indicating a better response for adolescents with mood symptoms than vegetative symptoms. Although, no relationships in improvements in mood/motivation and vegetative clusters were found controlling for baseline mood/motivation and vegetative symptoms; positive associations were found between cluster variables (mood, vegetative and total depression) over time.

Gender was also not found to moderate the relationship between improvement on mood and vegetative symptoms over time indicating no significant differences in the improvement between males and females. Overall, findings from the current investigation strengthen the results from previous studies regarding the timeline of symptom improvement with IPT-AST.