Introduction

Depression is a term used loosely to describe a number of conditions called depressive disorders that share similar symptoms. The term is frequently misleading since it is widely used by the general public to refer to brief upsets or moods, which are no more than the usual ups and downs of daily life. When mental health professionals use the term they are referring to much more complex concepts of disorder (abnormal states). Mental health professionals sometimes use the term "affective disorder" to refer to mood disorders (depression or mania).

Major depression (or major depressive disorder)

The diagnosis of major depression is made when a person has experienced more than two weeks of severe, pervasive and persistent depressive symptoms. Basically, the person has a low mood that shows little variation from day to day (although it is often worse in the morning), and is generally not responsive to what goes on around the sufferer. This state is associated with a reduced enjoyment of life and a loss of interest in previously pleasurable things (anhedonia), as well as lowering of self-esteem and self-confidence. Ideas of guilt or worthlessness are often present. These may be so severe as to amount to being delusions - convictions of guilt, which are quite irrational (psychotic depression). Energy levels are reduced and the person may become very tired after little effort, causing them to slow down and become much less active.

Sleep disturbance is common in depression. This is often a mix of having difficulty falling asleep; then broken, restless sleep; and finally waking several hours earlier than usual and being unable to get back to sleep. Loss of appetite (with weight loss) is common, as is a loss of interest in sex.

It is also common for a person with major depression to experience high levels of anxiety and agitation. Depending on the severity and number of depressive symptoms, such an episode of major depression may be described as mild, moderate, or severe. In very severe cases, as noted, a depressed person may develop psychotic symptoms.

Psychotic depression

When a depressive episode becomes very severe, the depressed person may lose touch with reality and begin to experience the symptoms of psychosis. (These symptoms are discussed in the Psychotic disorders brochures, and include developing odd, unreal beliefs and experiencing hallucinations.)

The psychotic symptoms are usually of a sad or depressing type, in keeping with the person's mood. For example, the people may come to believe they have lost all their money, or all their children, and have nowhere to live, or that they have a fatal but undiagnosed physical illness such as cancer. They may believe, (in a quite specific and concrete way), that their brain has gone, or that their abdominal contents have rotted away. The nature or content of these delusions is said to be 'colored by the mood'.

Although all forms of depression can be serious, psychotic depression is probably the most severe and distressing type. It may require urgent treatment, often in a hospital - especially if suicidal preoccupations are prominent, or if self-neglect, anorexia (not eating), dehydration and/or weight loss are judged to be a threat to life. As well as antidepressants, treatment will usually involve the use of antipsychotic medication to treat the psychotic symptoms. (For more information on antidepressants and antipsychotics, please go to Medications) Electro-convulsive therapy (ECT) has been demonstrated to be very effective in treating psychotic depression and usually provides fairly rapid relief. (For additional information, see Progress Assistance: Treatments and strategies: Electro-convulsive therapy)

Dysthymia or 'dysthymic depression'

Dysthymia refers to a depressed mood that is present for most of the time, which occurs in association with other symptoms of depression (such as problems with sleep, appetite or concentration) and has been present for at least two years.

Dysthymia is a condition that is very similar to major depression, with the similar symptoms, but not as severe. Although it is not as acutely disabling as some of the other forms of depression it can still cause significant problems and prevent a person from functioning at the best level or from enjoying life.

A related concept, minor depression, has been listed to describe chronic depressive states like dysthymia but which, unlike dysthymia, show periods of complete remission and freedom from symptoms.

Treatment of dysthymia usually involves the use of antidepressant medication together with some form of psychotherapy.

Bipolar disorder or 'manic' depression

Bipolar disorder (also known as manic-depression) is a disorder where mood and activity levels are very significantly disturbed, but with episodes of both mood elevation ("ups", "highs") and of mood depression ("lows", "downs").

Mania is the opposite of depression. A manic person will generally have tremendously, excessively and abnormally elated mood, and are often very irritable as well (or show sudden flashes of irritability and sometimes of tears, frequently for no obvious reason). These states show other features such as racing thoughts, very rapid speech, increased energy levels and very ambitious, grandiose and unrealistic plans for various projects. Where the symptoms are clearly there but are less severe, the state may be referred to as one of hypomania.

People suffering from the full-blown manic state are frequently psychotic (see the brochures - Psychotic disorders). They may have grandiose delusions, often believing that they are special people with a mission from God, or that they are misplaced historical figures. They may act on these delusions, for example, writing to monarchs and/or presidents and ordering other people around. The may believe that they are quite above the law- and certainly much more intelligent than those around them. They are usually without insight and, when manic or hypomanic, feel particularly well. It is the only state of illness in which the sufferer often feels better when they are actually ill than when they are actually well!

For a diagnosis of mania to be made, the above symptoms must last more than a week, or be severe enough to require treatment in a hospital. A person is not diagnosed as having an episode of mania if the symptoms are caused exclusively by drugs (e.g. amphetamines) or physical illness (organic affective disorder).

People with bipolar disorder will sometimes experience a 'mixed mood state', during which there time will be features of mania and depression occurring at the same time, or the mood may alternate from depressed to manic extremely rapidly (i.e. within minutes or hours).

The methods of treatment used in episodes of depression occurring in someone with bipolar disorder is essentially similar to that used in other sorts of depressive disorder, but antidepressants may make the person manic. Then, mood stabilizers are often used as well. The simple salt, lithium carbonate (LiCO3), is probably the best-known of these, but certain medicines used to treat epilepsy such as sodium valproate (Epilim) and carbamazepine (Tegretol), have also been shown to prevent abnormal fluctuations, whether up or down, in mood in people with bipolar disorder. Mood stabilizers, used alone, often maintain people a little bit on the depressed side of normal and it is common for a small dose of an anti-depressant to be combined with the mood-stabilizer for long-term maintenance.

Mood swings

What people often refer to as 'mood swings' are not usually bipolar or manic-depressive disorder. The severe extent of the mood swings seen in bipolar disorder is very much greater than what is seen in normal daily fluctuations of mood - even where someone is normally quite angry.

Cyclothymia or cyclothymic disorder is a term used to refer to a condition that is identical to bipolar disorder, but has less severe mood fluctuations. These fluctuations do not usually interfere with normal occupational functioning. Although the person does not have symptoms severe enough to make a diagnosis of bipolar disorder, his/her mood swings can still cause many problems, especially in social and domestic areas of functioning. Others do not regard him/her as ill but describe him/her as 'moody' or 'up and down'. This condition tends to be life long and is regarded as part of a person's personality.

However, cyclothymia may be severe enough to benefit from treatment of the same types as are used in bipolar disorder (mood stabilizing medications, antidepressants and psychotherapy).

Adjustment disorders

These are the sorts of depression that occur within three months of a person experiencing a stressful life event, such as getting divorced or having a serious car accident. Symptoms include marked distress, depressed mood, anxiety and irritability. These can occur with or without other physical symptoms such as disturbed sleep or appetite. Such states used to be referred to as 'reactive depression', a term which for many conveys the essence of what is happening better than the current 'adjustment disorder'. However, 'adjustment disorder' is preferred because it more clearly captures the fact that two issues are involve - one being the stressor, and the other, the ability of the individual to cope with the stressor. Stresses that appear to be disregarded by some are quite capable of crippling another.

Although feelings of sadness, and mild depressive symptoms, often occur in times of difficulty (and are to be expected), they are usually not severe or long-lasting enough to be diagnosed as depression or as an adjustment disorder. Generally, someone with an adjustment disorder will recover within six months, but treatment may be required. This might involve the use of antidepressants and psychotherapy.

Post-natal depression

Brief disturbances of mood are commonly seen within the first week of giving birth, and are called the 'baby blues'. These states usually disappear within a few days - ten at the most - and are almost certainly related to the rapid changes in hormone levels that occur after childbirth.

If these depressive symptoms persist, then a diagnosis of post-natal depression may be made. This occurs in about 10% of mothers and is more likely if the woman has had post-natal or other types of depression previously. It is also more likely if there have been pregnancy-related stresses (such as an illness, or complicated delivery), relationship difficulties, or if the mother has few people to provide her with help and support.

The condition responds to the same treatments used to treat other types of depression -support, medication and talking over problems. Electro-convulsive therapy (ECT) is thought to be particularly effective if the condition reaches psychotic intensity (puerperal psychosis).

Premenstrual tension

PMT is short for premenstrual tension and is the term most commonly used to describe a condition that occurs in women during the week leading up to menstruation. (It also known as pre-menstrual syndrome (PMS) and premenstrual dysphoric disorder.) This common disorder is characterized by symptoms related to:

• mood such as irritability, anxiety, and depression;
• behavior such as appetite and sleep disturbance; and
• physical symptoms which include headaches, bloated feelings and breast tenderness.

The cause or causes are not well understood but PMT may be mainly a result of changes in sex hormone levels that occur at that point of time in the menstrual cycle.

Many treatments have been used to treat PMT, but their efficacy is very inconsistent (although appear to work for some women). The first step in management usually involves verifying the diagnosis by careful observation of symptoms throughout the menstrual cycle, and by excluding other conditions that may cause similar symptoms (such as major depression).

When the diagnosis is established, various treatments may be selected depending on the most prominent symptoms - they include general measures together with a variety of drug approaches which include hormones, vitamins (vitamin B6 or pyridoxine), diuretics (to reduce bloating), antidepressants and mood stabilizers.

Organic affective disorder

Organic affective disorder is used to describe depressive disorders (less commonly mania or hypomania), which appear to result as a consequence of some other specific physical illness.

Several important brain disorders can cause typical depressive illness. Amongst these are Parkinson's disease, frontal lobe pathologies of various types, tumors, cysts and strokes. Depressive disorder is also seen after a severe head injury.

Apart from physical disorders with direct effects on the brain, certain other conditions which change body chemistry generally may produce depression, e.g. a thyroid gland deficiency (a state of reduced functioning of the thyroid gland) in which symptoms of depression are the major part of the symptoms. Similar glandular disorders affecting the pituitary and adrenal glands can have the same effect. Reduced flow of oxygen to the brain which can occur in lung and heart disease, or in a common condition known as sleep apnea (a disorder in which there is repeated interruption of breathing during sleep mainly manifested by loud snoring after a prolonged period of not breathing) can also produce depressive illness. Certain vitamin deficiency states may do likewise, especially deficiencies of vitamin B12 or folic acid. The list of such conditions is long and it is the task of mental health professionals, especially psychiatrists, to be aware of them.

Another important physical cause of depressive illness is the effect of certain drugs on the brain. These drugs include drugs used in the control of high blood pressure; steroid drugs such as cortisone and prednisone used in a wide range of complex medical disorders; and some agents used to treat cancer.

These conditions have the same range of symptoms as are seen in major depression and in bipolar disorder. There may be the additional symptoms of the primary physical disorder and symptoms may be mild or severe. In some cases, they respond immediately to specific treatment of the physical disorder as, for example, the treatment of thyroid dysfunction with thyroid extract or thyroxin. In other cases they may be very difficult to treat, particularly where damage has occurred to the brain as after stroke or trauma, or where damage is ongoing as in the case of a progressive tumor of the brain.