Types of depression

There are many different types and sub-types of depression that are currently used to describe people’s experience of depression.  However, it is important to understand that there has been considerable debate amongst the health and scientific communities over the classification of depression given the variety of possible causes and symptoms that may be experienced by individuals with depression.

Types of depression are mostly determined by the intensity of the symptoms, the duration of the symptoms, and the specific cause of the symptoms, if that is known. 

In recent times depression has been classified according to its severity, which may be useful for people who are unsure as to what level depression affects their lives (mainly mild to moderate cases), however, there are also other types of depression within these categories.  The following information attempts to explain the most widely diagnosed types of depression and their symptoms.

Mild/Minor Depression and Dysthymic Disorder

Moderate Depression

Major/Severe Depression

Bipolar Disorder (BPD) and Cyclothymic Disorder

Seasonal Affective Disorder (SAD)
 
Postnatal Depression (PND)

There are some older terms still used to describe depression that some people may come across.  These are:

Reactive depression – depression occurs as a result of external/environmental factors

Endogenous depression – depression occurs as a result of internal/genetic factors

It is now generally understood that both factors are involved in the occurrence of depression rather than either/or.

In addition, there is another classification set used to describe clinical depressive disorders in Australia according to The Black Dog Institute NSW.  It is based on the identification of neurological, psychological, and physical patterns and not solely on the severity of symptoms.

Melancholic - the classic form of biological depression. Its defining features include a more severe depression than is the case with non-melancholic depression, and psychomotor disturbance (cognitive processing difficulties, with slowed thoughts and impaired capacity to work or study and/or an observable motor disorder i.e. slowing and/or agitation of physical movements).

Melancholic depression is a relatively uncommon type of depression. It affects only 1-2 per cent of Western populations.  It has a low spontaneous remission rate and it responds best to physical treatments (for example antidepressant drugs) and only minimally (at best) to non-physical treatments such as counselling or psychotherapy.

Non-melancholic – in this case the depression is not melancholic, or, put simply, not primarily biological. Instead, it has to do with psychological causes, and is very often linked to stressful events in a person’s life, alone, or in conjunction with the individual’s personality style.

Non-melancholic depression is the most common of the three types of depression.  People with non-melancholic depression experience:

• a depressed mood for more than two weeks 
• social impairment (for example, difficulty in dealing with work or relationships).

Non-melancholic depression has a high rate of spontaneous remission because it is often linked to stressful events in a person’s life. Non-melancholic depression responds well to different sorts of treatments (such as psychotherapies, antidepressants and counselling), but the treatment selected should respect the cause (e.g. stress, personality style).

Psychotic - Psychotic depression is a less common type of depression and its symptoms include an even more severely depressed mood, more severe psychomotor disturbance, and  psychotic symptoms (either delusions or hallucinations), and over-valued guilt ruminations. Psychotic depression has a very low spontaneous remission rate. It responds only to physical treatments (such as antidepressant drugs).

Atypical – the term ‘Atypical depression’ has been chosen to express a possible form of depression that contrasts with the usual characteristics of non-melancholic depression.  E.g. rather than experiencing appetite loss the person instead experiences appetite increase; and sleepiness rather than insomnia. Someone with atypical depression is also likely to have a personality style of interpersonal hypersensitivity (that is, expecting that others will not like or approve of them).

The features of atypical depression include: the individual can be cheered up by pleasant events; significant weight gain or increase in appetite (especially to comfort foods); excessive sleeping (hypersomnia); arms and legs feeling heavy and leaden; a long-standing sensitivity to interpersonal rejection — i.e. the individual is quick to feel that others are rejecting of them.

For more detailed information, please visit The Black Dog Institute NSW. 

References

Dealing with depression – A common sense guide to mood disorders
Gordon Parker
2005

The ICD-10 Classification of Mental and Behavioural Disorders
World Health Organisation
1993

Understanding Depression
Maria Prendergast
2006

Black Dog Institute

Beyond Blue 

ANU