Sub-grouping non-melancholic depression from manifest clinical features

To determine whether clinical symptoms manifested during an episode of major depression are sufficient to allow meaningful sub-groups of non-melancholic depression to be identified.

A sample of 178 non-melancholic patients with a major depressive episode was studied. The initial set of clinical variables was refined to 38 (21 depression, 17 anxiety) items and a cluster analysis undertaken.

A four-cluster solution identified 'anxiety', 'irritability', 'depressed mood' and 'residual' clusters, with these labels clarified by reference to a large data bank of non-symptomatic variables. These analyses suggested that members of the first two clusters could be viewed as having spectrum conditions (whereby Axis I symptom states are able to be linked with precursor or prodromal states and personality).

We confirm the long-standing suggestion that the non-melancholic depressive class contains sub-groups of those with manifest states of anxious depression and of an irritable or 'hostile' depression, and that such manifest symptoms are likely to be rooted in and fed by temperament and personality characteristics. The delineation of such sub-groups should assist studies designed to identify underlying neurobiological underpinnings and clinical management of the non-melancholic depressive disorders.