Most people experience normal depressed moods. Such moods are usually not of major intensity, last less than two weeks, and don’t interfere with ability to function. The distinction between a normal depressed mood and a depressive disorder is crucial to understanding depression.
✰ Depressive disorders
Depressive disorders are more severe than a depressed mood state, last for at least two weeks and affect functioning at home and/or work.
There are three classes of clinical depressive disorders:
• non-melancholic depression;
• melancholic depression; and
• psychotic melancholia.
Melancholic depression and psychotic melancholia are less common depressive illnesses, affecting 1–2 percent of Western populations, with the numbers being roughly equal for men and women.
In comparison with the two other depressive classes, non-melancholic depression lacks specific defining features such as psychomotor disturbance (PMD), which assists in defining melancholic depression, or psychotic features, which, together with PMD, assist in defining psychotic depression. Thus, people with non-melancholic depression can usually be cheered up to some degree and are less likely to report significant concentration and memory problems. As with the other depressive disorders, those with a non-melancholic depression have a mood disorder (feel depressed, have a drop in self-esteem, and are self-critical) and experience many of the associated symptoms (such as appetite and sleep disturbance).
Non-melancholic depression is the most ‘common’ depressive disorder, affecting one in four women and one in six men in the Western world over their lifetime. It has a high ‘spontaneous remission’ rate, making accurate assessments of specific treatments difficult. In fact, response rates to quite different treatment approaches (for example, antidepressant drugs, psychotherapy and counselling) are very similar.
The depressed mood state in melancholic depression is generally more severe than in non-melancholic depression and PMD is evident. This sub-type has a low spontaneous remission rate and, before effective treatments were available, could last from months to decades. Its response rate to physical treatments (for example, antidepressant drugs) is high, but minimal to nonphysical treatments such as counselling or psychotherapy.
The depressed mood state and PMD are even more severe in psychotic melancholia than in melancholic depression, and a feature unique to this disorder is present—psychotic phenomena (delusions and hallucinations). This condition has a very low spontaneous remission rate. It responds only to physical treatments.
✰ The principal depression ‘patterns’
The common patterns experienced by those with the major depressive classes are described below, together with the common patterns of ‘normal’ depression.
Normal mood swings
Most people experience a pattern of fairly regular ‘ups and downs’ (for example, being ‘the life of the party’ one night and glum and flat the next). Such a pattern is known as a ‘cyclothymic’ personality style. These swings are not severe and do not seem distinctly ‘abnormal’ to others.
If depression is defined as being blue, sad, hopeless and helpless, and having feelings such as wanting to give up and being pessimistic about the future, then more than 90 per cent of people will admit to such a state several times a year. While these states may range from mild to troublesome and last from minutes to hours to a couple of days, most people expect them to settle by themselves or with the use of personal coping strategies. Normal mood swings do not affect day to day functioning.
In non-melancholic depression, a depressed mood is present for more than two weeks and is accompanied by social impairment (for example, difficulty in dealing with work or relationships). There is no observable PMD, nor are there psychotic features, and the features of the clinical mood state can vary. Spontaneous remission (that is, getting better naturally or ‘out of the blue’) is common.
There are several differing sub-types of non-melancholic depression, which are more likely to occur in people with certain personality styles or who have a primary anxiety disorder. These personality styles and the higher level of anxiety increase the risk of developing depression (and the likelihood of it persisting) when a person is faced with certain stressful events. Personality style accounts for the variable mood state features found in non-melancholic depression, and indicates why quite contrasting therapies (for example, those addressing predisposing factors, others directed at anxiety, and still others focusing on the depression) may all be quite effective.
The mood state in melancholic depression is more severe than in non-melancholic depression. It lasts more than two weeks and involves moderate to severe social impairment, as well as visible PMD (for example, retardation or agitation).
Melancholic depression is primarily biological, and spontaneous remission is unusual. It tends to run in families. The first few depressive episodes may develop in response to stress, but later episodes may appear ‘out of the blue’ or come on after a minor problem.
Melancholic depression may also develop as a result of exposure to certain drugs (licit or illicit) and some diseases. These can act like external stress, disrupting some of the brain’s neural circuits (the basal ganglia and frontal cortex links), causing depression, PMD and concentration problems. A similar disruption happens in Parkinson’s disease.
For some people, especially those without any family history of melancholia, an episode of melancholic depression can come on for the first time late in life, as age changes in the brain disrupt relevant brain (or neural) circuits. Before effective treatments became available, depression could remain for years without any relief, or before spontaneous recovery.
As noted, active physical treatments are almost invariably needed, but differing antidepressant drugs range widely in their effectiveness in treating this sub-type.
Electroconvulsive Therapy (ECT) may be effective but it is rarely needed. Psychotherapy and counselling may also be used in addition to such physical treatments. However, as the main underpinning mechanism in melancholic depression is biological, not psychological, these treatments are not appropriate as primary therapies.
In psychotic melancholia, the depressed mood is extremely severe and present for more than two weeks. There is severe social impairment and PMD, and psychotic features (such as delusions) are evident due to additional neural circuits in the brain being disrupted. As with melancholic depression, psychotic melancholia can first appear late in life.
Preferred treatments are biological and physical, with the older antidepressant classes appearing to be more effective than many of the newer classes. However, antidepressant drugs alone are usually less effective than combination antidepressant and tranquilliser treatments (antipsychotic or neuroleptic medication), or even ECT in some instances.
(extracted from) Dealing with Depression: A Commonsense Approach to Mood Disorders y Gordon Parker, published by Allen & Unwin