Background

Depressions that fail to meet the diagnostic criteria for major depressive disorder (MDD) may be underdiagnosed and undertreated in adolescent population. Traditionally, they are not considered as serious conditions and the phenomenological nature and clinical correlates of these disorders are largely unknown. In the present study, we used a large, representative and age-standardized sample of adolescents to examine the phenomenology and clinical correlates of minor depression, a poorly understood condition included in the category of Depressive Disorder Not Otherwise Specified in Diagnostic and Statistical Manual of Mental Disorders–Fourth Edition–Text Revised (DSM-IV-TR). Methods

909 girls and 945 boys, with mean age of 14, were interviewed by professionals using the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA). Results

Although clearly milder condition than MDD, minor depression was associated with marked suicidal thoughts, plans and attempts, recurrences and a high degree of comorbidity. At this early age, despite that 14% of adolescents under 15 had suffered from depressive conditions with severe clinical implications, most of them failing to meet the diagnostic threshold for MDD, only 1.7% had received any psychiatric treatment. 40% of depressive adolescents who had attempted suicide had no contact with mental health services. Limitations

Analyzed in a cross-sectional setting, no conclusions about long-term implications could be made. Conclusions

The results highlight the clinical and public health significance of non-MDD depressions, e.g. minor depression, which need to be more carefully identified and treated at early age.