Clinical features of mood disorders and mania.
- Acute depression
- Mild depression
- Major depression with or without melancholia
- Major depression with psychotic features
- Recurrent depression
- Recurrent major depression
- Recurrent brief depression
- Seasonal depression
- Chronic depression
- Chronic major depression
- Acute mania
- Mania without psychotic features
- Mania with psychotic features
- Recurrent bipolar episodes
- Bipolar type I disorder
- Bipolar type II disorder
- Rapid cycling disorder
- Chronic bipolar disorder
- Chronic bipolar major depression
- Acute mixed episode
In both DSM-IV (1)and ICD-10 (2) the term ‘affective' has been replaced by the term ‘mood' to emphasize the duration of the episodes of clinical depression or mania. ‘Affective' often refers to emotional states of briefer duration than ‘mood' or to milder degrees of symptoms. The duration of depressive mood varies widely from less than 1 month to about 2 years. (3)
Non-mixed states of depression and mania are clinical opposites. About 10 per cent of patients will have both depressive and manic recurrence, and the term bipolar traditionally refers to recurrent episodes of both depression and mania. (Not all mental disorders showing an episodic course should be classified as mood disorders.) There are also chronic mood disorders. The term chronic major depression is used to describe persistence of the symptoms for more than 2 years which, in accordance with DSM-IV and ICD-10, is the upper limit of a depressive episode. Manic episodes usually last from a week to 6 months. Chronic mania is very rare. However, milder symptoms may persist as depression (dysthymia) and a manic or mixed state (cyclothymia).
It has been argued (4) that the current editions of the DSM and ICD classifications are essentially attempts to standardize the Kraepelinian categories. While this holds true to a large extent, one of the limitations of DSM-IV and ICD-10 is the use of many subcategories resulting in much comorbidity, especially among the depressions. Anxiety is an important symptom of depression and aggression is an important symptom of mania.
Clinical research with symptom rating scales such as the Hamilton Depression Scale (HAM-D) has shown that about ten symptoms are sufficient to characterize the syndrome of most of the acute depressive states. (5) Table 1shows these ten symptoms of acute depressive disorder as they appear in DSM-IV or ICD-10. The only difference between the two systems is that ‘loss of self-esteem' is a separate symptom in ICD-10, whereas in DSM-IV it is included in the symptom of ‘feelings of worthlessness and inappropriate guilt'. Thus DSM-IV has nine symptoms and ICD-10 ten symptoms for measuring the severity of depressive states. Mild, moderate (major), and psychotic depressions are considered, on the basis of the number of symptoms, as three different diagnostic categories in DSM-IV and ICD-10.
- Depressed mood most of the day, nearly every day
- Markedly diminished interest or pleasure in all, or almost all activities most of the day, nearly every day
- Loss of energy or fatigue, nearly every day
- Loss of confidence or self-esteem
- Unreasonable feelings of self-reproach or excessive or inappropriate guilt , nearly every day
- Recurrent thoughts of death or suicide or any suicidal behaviour
- Diminished ability to think or concentrate or indecisiveness, nearly every day
- Psychomotor agitation or retardation, nearly every day
- Insomnia or hypersomnia, nearly every day
- Change in appetite (decrease or increase)
Above: Table 1 Acute depression as defined in DSM-IV and ICD-10
In the following each of the three diagnostic categories—mild, moderate (major), severe (psychotic)—will be described with reference to Table 1 to illustrate the development of depression from mild to major. A layman's description of these stages is shown in quotations from the American novelist William Styron (Box 1), who at the age of 60 described his own unipolar depressive episode in his memoir Darkness Visible. (6) Styron's description shows how anxiety is an important symptom of depression from its onset and continues over several weeks. When the suicidal symptoms became severe, Styron was admitted to the Yale New Hospital.
A decrease in positive well being or a lack of interests is often the first symptom of depression: ‘walks in the woods, became less zestful' ( Box 1). Many patients with mild depression describe themselves as ‘distressed' rather than ill. When people describe their feelings in response to life stress, they often speak of anxiety and depression. (7) However, the lowering of mood in the states of distress is much more variable than that in mild depression and lasts for less than a week. The first three symptoms in Table 1 are the core symptoms of mild depression. They are present most of the day, nearly every day, for at least 2 weeks, and a person with a mild depression usually has difficulty in carrying on with his or her normal activities. Diagnosis of mild depression according to ICD-10 requires at least two of the first three symptoms in Table 1, as well as at least two of the remaining seven symptoms. Insomnia and diminished ability to concentrate are common.
Elderly patients with mild depression may experience fatigue, insomnia, and poor concentration associated with ageing rather than with illness. Only about half of patients suffering from depression consult their family doctors, and those who do consult their doctors are more severely depressed. (8) Those patients who are treated for depression have a much better outcome than those who do not consult their doctors. (8)
Major depression with or without melancholia
The cardinal triad of symptoms of depression is as follows: emotional symptoms, psychomotor symptoms, and negative beliefs. Notsurprisingly, this triad is more obvious in major depression than in mild depression. Diagnosis of major depression according to DSM-IV requires at least five of the nine symptoms in Table 1, and ICD-10 requires six of the ten symptoms in Table 1. Negative beliefs such as ‘loss of self-esteem' or ‘inappropriate guilt' are the core symptoms of major depression. Inappropriate guilt is experienced as punishment for past misdeeds (prior to the current episode of depression). The prevailingelement of negative beliefs is a sense of loss which is associated with lower self-esteem experienced retrospectively. (9) The symptom which discriminates best between anxiety states and major depressive disorder is guilt. (10)
The stages from decreased positive well being through mild depression to major depression without psychotic features (from William Styron, Darkness Visible (6) )
- The shadows of nightfall seemed more sober, my mornings were less buoyant, walks in the woods became less zestful, and there was a moment during my working hours when a kind of panic and anxiety overtook me, just for a few minutes, accompanied by a visceral queasiness ...
- ... As the disorder gradually took full possession of my system, I began to conceive that my mind itself was like one of those outmoded small-town telephone exchanges, being gradually inundated by flood-waters ...
- ... I particularly remember the lamentable near disappearance of my voice ... The libido also made an early exit ...food, like everything else within the scope of sensation, was utterly without savour ...
- ... My few hours of sleep were usually terminated at three or four in the morning, when I stared up into yawning darkness... I'm fairly certain that it was during one of these insomnia trances that there came over me the knowledge that this condition would cost me my life, if it continued on such a course ... I had not conceived precisely how my end would come. In short, I was still keeping the idea of suicide at bay ... What I had begun to discover is that the gray drizzle of horror, induced by depression, takes on the quality of physical pain ...
Psychomotor retardation is more common in younger depressed patients; psychomotor agitation is more common in elderly patients. Psychomotor retardation is manifested not only in decreased motor activity (e.g. fixed facial expression, reduced gestures, and slow movements) but also in decreased verbal activity, concentration difficulties, and emotional withdrawal. Psychomotor agitation can range from hand-wringing and restlessness to almost continuous pacing.
Both in DSM-IV and ICD-10, major depressive states can be further specified as a melancholic or somatic syndrome. In earlier descriptions (including Freud's ‘Mourning and melancholia' (11) ), endogenous or somatic depression is distinguished from psychogenic or reactive depression by ‘early morning awakening' and ‘depression regularly worse in the morning'. These two signs are the only features of somatic or melancholic depression not included in the list of symptoms in Table 1. Strictly speaking, diurnal variation in symptoms is not itself a symptom but rather a description of their course. The most ‘somatic' symptom in Table 1is change in body weight (Styron had lost 20 to 25 pounds over a period of 6 weeks, when the illness developed into a major depression). (12)
Styron's depression (Box 1) included the somatic feature of early morning awakening and suicidal thoughts. The latter are not just a consequence of the other symptoms. Styron described how during depression he could still keep ‘...the idea of suicide at bay...'. At a later stage (not shown in Box 1), just before he was admitted to hospital, Styron tried to write a suicide letter. Suicidal thoughts were often present late at night, when anxiety symptoms had lifted. (12)
Measurements of social behaviour and subjective state have shown that acute major depression is among the most disabling and distressing of medical disorders. (13) The constant mental pain and the suicidal symptoms seriously affect quality of life. The suicidal risk in major depression is especially high when psychomotor retardation is improving under treatment. The treating physician or the relatives typically observe improvement in the depressive symptoms before the patient does, because psychomotor retardation improves before mood state or hopelessness.
The risk is especially high in socially isolated people. Major depression has the highest risk of suicide of all mental disorders, and all patients with major depression should be assessed for the risk of suicide.
Previous editions of DSM and ICD included ‘involutional melancholia', which was considered to be a distinct entity, among the late-onset types of depression. However, it is now regarded as a typical major depression.
Major depression with psychotic features
According to DSM-IV or ICD-10, the term ‘psychotic depression' is not synonymous with endogenous or melancholic depression. This agrees with Kraepelin (14) and Hamilton (15) who used the term ‘psychosis' to refer to the severity of symptoms. As stated by Hamilton: (15) ‘... a schizophrenic patient, who has delusions is not necessarily worse than one who has not, but a depressive patient who has is much worse ...'. This statement is also valid for mania.
Mood-congruent psychotic features can be considered as a severe degree of symptoms such as guilt and hypochondriasis. Among the case histories selected to illustrate the ICD-10 diagnoses, that of a 35-year-old male patient referred to as the ‘Night Walker', illustrates severe depression with mood-congruent psychotic symptoms: (16)
...he spoke in a low voice and displayed belief in a fatal illness, from which he was going to die. He said he contaminated others and that he felt guilty about the death of a distant relative...He was evil, worthless, and did not deserve to live... Physical and neurological examinations showed no abnormalities except for the evidence of severe weight loss...
Recurrent major depression
After a single episode of major depression around 85 per cent of patients experience recurrent episodes. (17) While the first episode of major depression is often provoked by a negative life event such as loss of job, retirement, marital separation. or divorce, subsequent episodes are often unprecipitated (positive life events can also provoke depression). Depressive episodes typically increase in frequency and duration as they return. (18) This phenomenon has been explained by ‘kindling', a process in which repeated stimulation causes an escalating response. (19) Usually, the intervals between episodes of unipolar depression are symptom free, but some patients experience dysthymia between episodes. Such cases have been called ‘double depression'. (20)
Recurrent brief depression
The symptoms of recurrent brief depression, which was first described by Angst, (21) are similar to those of major depression (Table 1) with regard to both number and severity. However, they do not meet the requirement that an episode should last for 2 weeks or more. The diagnosis of recurrentbrief depression has not been adopted fully in DSM-IV, but it is included in ICD-10. It should be distinguished from recurrent suicidal behaviour, for example in patients with borderline personality disorder.
Reccurrent brief depression occurs in some patients with Parkinson's disease. In contrast, post-stroke depression is similar to major depression.(22)
Seasonal depression is seen most frequently in winter, and less frequently in summer. In DSM-IV, seasonal depression has been adopted as a specifier (rather than a diagnostic category) which can be applied not only to recurrent depression but also to bipolar disorder. The seasonal episodes (e.g. winter depression) have to outnumber any non-seasonal depressive episodes in the same patient. In ICD-10 only seasonal depression is briefly mentioned, and that in an annex for disorders under consideration.
According to DSM-IV, the symptoms of seasonal depression are similar to those of major depression. However, Kasper and Rosenthal (23) repeated that the symptoms differ from those of major depression, with hypersomnia, overeating, carbohydrate craving, and weight gain. In a meta-analysis of 61 studies of seasonal patterns of suicide, Goodwin and Jamison (18) showed that suicide is 10 to 20 times more common in spring (with a peak in May) than in winter or summer. There was also a small peak in October. This pattern is consistent with the peak times of hospital admission for depressive episodes. These findings support the view (23) that seasonal winter depression is an atypical type of major depression.
In both DSM-IV and ICD-10 ‘chronic' refers to an episode with a duration of 2 years or more. ‘Double depression' is by definition a form of a chronic depression, because dysthymia is defined as lasting for at least 2 years.
Chronic major depression
In DSM-IV, but not in ICD-10, major depression is specified as chronic if the criteria for major depression have been met continuously for at least the past 2 years. Treatment-resistant depression is not a diagnosis, but a term that describes many chronic major depressions.
Both in DSM-IV and ICD-10 dysthymia refers to symptoms of mild depression which have persisted for at least 2 years. The symptoms are similar to those in Table 1, except for ‘excessive guilt', ‘psychomotor changes', and ‘suicidal thoughts'. Symptoms fluctuate more than in major depression,and (in contrast with seasonal depression) they are ‘typical' including insomnia, lack of appetite, or poor concentration. In ICD-10, but not in DSM-IV, the symptom of social withdrawal is included as a characteristic symptom of dysthymia. The category ‘depressive neurosis' which appeared in earlier editions of the classification included a similar symptom referred to as introversion. (5)
The clinical features of mania form are more distinct than those of depression. (24,25) Symptom rating scales for mania parallel to the Hamilton Scale for Depression have been developed. (26,27)
Table 2 shows the items listed in both DSM-IV and ICD-10. The only difference is that ICD-10 includes ‘increased sexual activities' asa separate item, whereas in DSM-IV it is listed under ‘risk-taking behaviour'. Hence, ICD-10 has nine items and DSM-IV has only eight items. ‘Elevated' and‘irritable' mood are combined in both classifications (item 1, Table 2), as are ‘increased social activities' and ‘psychomotor agitation' (item 7, Table 2).
Table 2 Acute mania as defined in DSM-IV and ICD-10
Box 2 shows the three stages of mania observed among inpatients before treatment. Whereas most depressive episodes are treated outside hospital, mania is usually treated in hospitals. Therefore most research on mania is still carried out in the hospital setting. The study by Carlson and Goodwin (28) is among the few longitudinal studies in which untreated inpatients have been observed systematically; Box 2 is a modified version of their findings. As in the previous discussion of depression, self-reports will also be referred to.
The three stages of the acute manic episode as observed in untreated inpatients
- Hypomania - Increased well-being and/or irritable mood, but still with sufficient control over the conditions; more busy; pressured speech; makes more telephone calls; seductive
- Mania - Nearly always pleasant and cheerful. Occasionally losing insight and co-operation, impulsive, angry; very hyperactive, less sleep, more pressure of speech, makes repeated telephone calls; racing thoughts, more expansive, some grandiosity
- Mania with psychotic features - Emotionally labile, can be very angry, very intrusive. Unco-operative, severely agitated, no sleep, very talkative, loud; flight of thoughts, grandiosity, religious delusions ‘hearing God', sexually very preoccupied' Modified from Carlson and Goodwin (28) .
Hypomania can be the first stage of a spiralling upswing of mood (Box 2). The main symptom of hypomania is usually intense well being but irritability is also seen. Normal happiness is transient, lasting from minutes to hours. To be diagnosed as hypomania, the elevation of mood must last for at least 4 days. The change of mood is often quite different from any seen when the patient is well.
The cardinal triad of mania comprises emotions, psychomotor symptoms, and expansiveness or increased self-esteem. A slight psychomotor restlessness and some pressured speech are often seen; for example, the person makes more frequent telephone calls. These symptoms are not severe enough to cause marked impairment in social or occupational functioning.
Jamison (29) has described this phase as follows: ‘...When you're high it's tremendous. The ideas and feelings are fast and frequent ...Shyness goes, the right words and gestures are suddenly there, the power to captivate others a felt certainty...Sensuality is pervasive and the desire to seduce and be seduced irresistible'. The shyness or introversion seen in mild depression or dysthymia contrast with the lack of shyness and extraversion seen in the hypomanic patient.
Mania without psychotic features
In mania the elevated spirit seen in hypomania is often mixed with irritability and hostility. Jamison (29) has described the change: ‘Humor and absorption on friends' faces are replaced by fear and concern. Everything previously (in the hypomanic state) moving with the grain is now against—you are irritable, angry, frightened, uncontrollable...'.
The psychomotor symptoms of mania are restlessness and less need for sleep. There is pressure of speech; the patient talks more and in a louder voice. There is intrusive behaviour, arguments, and attempts to dominate others. Expansiveness is manifested as increased self-esteem; for example, the patient clearly overestimates his or her own capacities or hints at unusual abilities. Jamison (29) described how in periods of mania she did not worry about money: ‘The money will come from somewhere; I am entitled; God will provide. Credit cards are disastrous, personal cheques even worse ... mania is a natural extension of the economy ... So I bought precious stones, elegant and unnecessary furniture, three watches within an hour (in the Rolex rather than Timex class)...'.
To be diagnosed as a manic episode, the disorder should last at least a week. The criteria for mania are elevated or clearly irritable mood, and at least three of the symptoms listed in Table 2. These symptoms should be severe enough to cause marked impairment in occupational functioning. Hospital admission is often needed to prevent the patient harming himself or others.
Mania with psychotic features
Psychotic states of mania are characterized by greater pressure of speech, more open hostility, severe agitation, no need for sleep, flight of thoughts, severe distractibility, and grandiose delusions. In younger people psychotic mania is often misdiagnosed as schizophrenia. (30) In hospital the increased social contact of manic patients is clearly different from the emotional bluntness of schizophrenics. The intrusive behaviour seen in severe mania is of an extremely dominating and manipulative nature, out of context with the setting. Secondary persecutory delusions often develop. The expansive religious delusion ‘hearing God' should be differentiated from the schizophrenic patient's religious hallucinations. Both DSM-IV and ICD-10 differentiate between mood-congruent psychotic symptoms (such as grandiose delusions of religion and voices supporting the patient's superhuman powers) and mood-incongruent psychotic symptoms (which are often the secondary delusions of persecution mentioned above).
Recurrent bipolar episodes
Only about 10 per cent of patients with ‘manic–depressive' disorder have mania. Kraepelin, who followed hundreds of patients with manic–depressive illness, observed very few with only recurrent manic episodes. (14) Recurrent manic episodes are more often interspersed with depressive episodes. Mixed states may emerge with the simultaneous presence of depression and manic symptoms (see discussion of acute mixed episodesbelow). About 85 per cent of patients with an acute episode of mania will run a chronic episodic course. (17)
Bipolar type I disorder
This is the classic manic–depressive illness with episodes of depression fulfilling the criteria of major depression and episodes of mania (with or without psychotic features).
Bipolar type II disorder
This category appears in DSM-IV but not in ICD-10. It is a disorder with episodes of hypomania but not mania, and episodes of major depression. The episodes of hypomania should not be confused with brief states of elevated mood which often follow the remission of a major depression.
Rapid cycling disorder
In DSM-IV rapid cycling disorder is a specifier; in ICD-10 it is mentioned only in an annex for disorders under consideration. In DSM-IV it can be applied to both bipolar type I and bipolar type II disorders. There should have been at least four episodes fulfilling the criteria of major depression, mania, hypomania, or mixed mood disorder in the previous 12 months. The episodes are demarcated by either partial or full remission for at least 2 months or a switch to an episode of opposite kind.
Chronic bipolar disorder
Chronic mania is rarely seen. DSM-IV has a category for chronic bipolar major depression. Both DSM-IV and ICD-10 include cyclothymia.
Chronic bipolar major depression
Chronic major depression can occur in bipolar disorders. However, the diagnosis of chronic bipolar major depression can be applied only if it is the most recent type of mood episode. The criteria of major depression symptoms should have been met continuously for at least the previous 2 years.
Previously this was considered to be a personality disorder or the first stage of a bipolar illness. The essential feature of cyclothymic disorder is a persistent fluctuating mood disturbance including numerous periods of depressive symptoms. These are periods, not episodes, of hypomania or depression. Thus it is a disorder of subsyndromal mood swings analogous to dysthymia in unipolar depression. About one-third of patients with cyclothymic disorder will develop bipolar disorder. (18)
Acute mixed episode
Jamison (29) has argued that the term ‘bipolar' perpetuates the notion that:
...depression exists rather tidily segregated on its own pole, while mania clusters off neatly and discretely on another. This polarisation of two clinical states flies in the face of everything that we know about the fluctuating nature of manic–depressive illness...and it minimizes the importance of mixed manic–depressive states...
In the acute mixed episode, it is the rapid change from one mood state to the other which is characteristic. The mixture of manic and depressive symptoms is the essential feature of mixed episodes. It is not a bipolar course of symptoms, but the presence of major depression and mania nearly every day. DSM-IV requires that the duration of the mixed episode should be at least 1 week; ICD-10 requires at least 2 weeks.
Kraepelin (31) described transitory mood of depression in acute manic states. Transitory moods of depression have been recorded in manic patients using a rating scale administered by the nursing staff. (32,33) Such short-lived states of ‘depression' in patients with acute mania should be referred to as ‘microdepressions' and not mixed episodes. Winokur (34) described ‘microdepressions' most clearly:
...If one allows a manic patient to talk, one will note that he shows fleeting episodes of depression embedded within mania (‘microdepressions'). He may be talking in grandiose and extravagant fashion and then suddenly for 30 seconds breaks down to give an account of something he feels guilty about...
His eyes will fill with tears but in 15 to 30 seconds he will be back to talking in his expansive fashion.
Frances et al. (35) declared that DSM-IV was moving from reliance on expert consensus to a greater emphasis on empirical evidence. In DSM-III and DSM-IV the diagnostic criteria were based on groups of symptoms which varied together over time. The ICD-10 and DSM-IV criteria for acute and recurrent episodes of mania and depression are in keeping with the accumulating clinical research. (5,18,36) Severity is a key dimension in both depression and mania. (37) The core symptoms of mania and depression shown in Table 1and Table 2are sufficient to measure the severity of the states and to discriminate between categories.
The former dichotomy between neurotic and endogenous depression has been put aside in favour of the view that, over time, patients can have both ‘neurotic' depression (dysthymia) and ‘endogenous' (major) depression (‘double depression'). Also, only the most severe major depressions are ‘psychotic', and not all major depressions are endogenous. Only the dichotomy between unipolar and bipolar disorders remains. This phenomenological approach to the clinical features of affective mood disorders and mania has high interclinician reliability. (5)
Reports from patients themselves have also been included in this article. Self-rating scales and questionnaires for depression have shown that depressed patients without psychotic symptoms can give consistent self-reports of their feelings. (5) New questionnaires or scales have been based on the symptoms in Table 1and Table 2. For example, the Beck Depression Inventory has recently been modified to cover better the items in Table 1. (38) Another depression questionnaire is based directly on Table 1, (13) as is an interview scale for major depression. (39) A mania scale covering Table 2 has been released. (40)
All depressed patients should be assessed for the risk of suicidal behaviour. Most answer such questions truthfully. In contrast, the manic patients describe themselves as ‘normal' (41) or respond in a so-called ‘manic game'. (42) This ‘manic game' can develop into potentially dangerous behaviour such as aggressive car driving, foolish business investments, or unusual sexual behaviour. It is a measure of good practice that the psychiatrist has the time and professional skills to convince the manic patient of the need for a short stay in the secure setting of a hospital.
The fluctuating or mixed nature of clinical depression and mania often requires simultaneous use of depression and mania rating scales to measure outcome of treatment (short-term as well as long-term).
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