Subthreshold depression in older subjects: an unmet therapeutic need.

Major depression, defined according to DSM IV TR criteria, is less common in older subjects, while other types of depression are two to three times more prevalent. This heterogeneous group of disturbances has received different names: depression not otherwise specified, minor depression, subthreshold or subsyndromal depression. Moreover, each condition has been defined using heterogeneous criteria by different authors. The term of subthreshold depression will be adopted in this position statement. Subthreshold depression has been associated with the same negative consequences of major depression, including reduced well being and quality of life, worsening health status, greater disability, increased morbidity and mortality. Nevertheless, there is a dearth of clinical trials in this area, and therefore older patients with subthreshold depression are either not treated or they are treated with the same non pharmacological and pharmacological therapies used for major depression, despite the lack of supporting scientific evidence. There is an urgent need to reach a consensus concerning the diagnostic criteria for subthreshold depression as well as to perform clinical trials to identify effective and safe therapies in this too long neglected patient group.