SUBSYNDROMAL SYMPTOMATIC DEPRESSION - EVIDENCE FOR A NEW MOOD DISORDER

There is very strong evidence in the literature indicating that the pr esence of subthreshold depressive symptoms is not a benign clinical co ndition. At least 5 separate investigational groups, including our own , have confirmed that the presence of depressive symptomology not reac hing the diagnostic threshold for a DSM-III-R mood disorder diagnosis is correlated with social dysfunction, work impairment and absenteeism , and the potential risk of future episodes of major depression. We ha ve labelled this condition 'subsyndromal symptomatic depression (SSD), . A secondary analysis of the National Institute of Mental Health Epid emiological Catchment Area (ECA) Programme database has demonstrated t hat SSD has a 1-year prevalence of approximately 8% in the general pop ulation. The majority of those with SSD were female (approximately 63% ) and they presented with a clinical symptom picture that closely rese mbled that of major depression. However, it was notable that the featu re of 14 days of dysphoria/anhedonia, which is a required criterion fo r a mood disorder diagnosis in the DSM-III-R system, was absent from t hese patients. It was also noted that patients with SSD more frequentl y received social welfare and disability benefits than did the general population without depressive symptoms. We have concluded that SSD do es represent a significant clinical problem that is not covered by any DSM-III, DSM-III-R or DSM-IV mood disorder diagnosis. Furthermore, th is disorder is of considerable importance in public health. An ongoing clinical trial is investigating the efficacy of fluoxetine in SSD.