Introduction
Of all the major psychiatric syndromes, schizophrenia is perhaps the most difficult to define and describe. This partly reflects the fact that, over the past century or more, widely divergent concepts have been held in different countries and by different people. Although there is now a greater consensus, substantial
uncertainties remain. Indeed, schizophrenia remains the best example of the fundamental issues with which psychiatry continues to grapple—concepts of disease, classification, and aetiology. Here, we start with an introduction to the major symptoms and other important clinical features.
Clinical features
In this section, it is assumed that the reader has read the descriptions of symptoms and signs in Chapters 1 and 3, which include definitions of many of the cardinal features of schizophrenia. These have classically been divided into two groupings:
● Positive symptoms. These are delusions and hallucinations, the most florid and well-known types of symptoms
of schizophrenia. Types of delusion and hallucination (called first-rank symptoms, discussed below)
carry greater weight in the diagnosis and help distinguish schizophrenia from other psychotic disorders.
● Negative symptoms. These are called ‘negative’ symptoms because they reflect a loss of normal functioning.
They are often listed as ‘four As’: alogia (decreased spontaneous speech), avolition (decreased motivation), affective flattening (lack of emotional expressivity, but not depression) and anhedonia. (These ‘four As’ are related to but distinct from Bleuler’s ‘four As’ described in Box 11.5.)
In recent years, other features of schizophrenia have been grouped together in two further categories:
● Behavioural disorganization. This includes formal thought disorder (abnormalities in the flow and sequence of thoughts; in the past this was often considered as a positive symptom) as well as inappropriate affect and bizarre behaviour.
● Cognitive symptoms. The extent and significance of
attentional and memory impairments in schizophrenia, discussed below, has been increasingly recognized, and hence they are now often considered as a
separate symptom category.
The predominant symptoms differ between acute schizophrenia and chronic schizophrenia, and the further description of the clinical syndrome is divided on this basis. Briefly, the acute syndrome is dominated by positive symptoms, with subtypes of acute schizophrenia classically recognized based upon the relative prominence of different positive symptoms. Many patients recover from the acute illness, but progression to the chronic syndrome is also common. Chronic schizophrenia is characterized by negative symptoms; once the chronic syndrome is established, few patients recover completely. Note, however, that the acute versus chronic distinction is an oversimplification; all features of schizophrenia can occur, and co-occur, at any phase of the illness.
For review of the clinical features of schizophrenia, see Arango and Carpenter (2011). For review of negative symptoms, see Marder and Galderisi (2017).
Acute schizophrenia
In acute schizophrenia, positive symptoms predominate, and are often florid. Behavioural disorganization, especially formal thought disorder, is also prominent. Negative symptoms are less common and cognitive deficits less apparent, although this is partly because they are masked by the positive symptoms.
The vignette in Box 11.1 illustrates several common features of acute schizophrenia, including prominent persecutory delusions, with accompanying hallucinations, gradual social withdrawal and impaired performance at work, and the idea that other people can read one’s thoughts.
In appearance and behaviour some patients with acute schizophrenia are entirely normal. Others seem changed, although not always in a way that would immediately point to psychosis. They may be preoccupied with their health, their appearance, religion, or other intense interests. Social withdrawal often occurs— for example, spending a long time in their room, perhaps lying immobile on the bed. Some patients smile or laugh without obvious reason. Some appear to be constantly perplexed, while others are restless and noisy, or show sudden and unexpected variability of behaviour.
The speech often reflects an underlying thought disorder. In the early stages, there is vagueness in the patient’s talk that makes it difficult to grasp the meaning. Some patients have difficulty in dealing with abstract ideas. Other patients become preoccupied with vague pseudoscientific or mystical ideas. Thought disorder is reflected in the loosening of association between expressed ideas, and may be detected in illogical thinking (e.g. ‘knight’s move’ thinking) or talking past the point (vorbeireden). In its severest form, the structure and coherence of thinking are lost, so that utterances are jumbled (word salad or verbigeration). Some patients use ordinary words or phrases in unusual ways (metonyms or paraphrases), and a few coin new words (neologisms). Disorders of the form (or stream) of thought include pressure of thought, poverty of thought, thought blocking, and thought withdrawal; some of these constitute first-rank symptoms (see Boxes 11.2 and 11.3).
Auditory hallucinations are among the most frequent symptoms. They may take the form of noises, music, single words, brief phrases, or whole conversations. They may be unobtrusive, or so severe as to cause great distress. Some voices seem to give commands to the patient. Some patients hear their own thoughts apparently spoken out loud either as they think them (Gedankenlautwerden) or immediately afterwards (echo de la pensée), and some voices discuss the patient in the third person or comment on his actions; these are first-rank symptoms (see Box 11.3). Visual hallucinations are less frequent, and usually occur together with other kinds of hallucination. Tactile, olfactory, gustatory, and somatic hallucinations are reported by some patients. They are often interpreted in a delusional way—for example, hallucinatory sensations in the lower abdomen are attributed to unwanted sexual interference by a persecutor.
Delusions are almost invariable in acute schizophrenia, although primary delusions are infrequent and are difficult to identify with certainty. Delusions may originate against a background of so-called primary delusional mood (Wahnstimmung). Persecutory delusions are common, but are not specific to schizophrenia, as they also characterize delusional disorders and occur in all psychoses (see Chapter 12). Less common, but of greater diagnostic value, are delusions of reference and of control (passivity), and delusions about the possession of thought. The latter are delusions that thoughts are being inserted into or withdrawn from one’s mind, or ‘broadcast’ to other people. Some of these symptoms are first-rank symptoms (Box 11.3).
Insight is almost always impaired. Most patients do not accept that their experiences result from illness, but usually ascribe them to the malevolent actions of other people.
Orientation is usually normal, although this may be difficult to determine if there is florid thought disorder or if the patient is too preoccupied with their psychotic experience to attend to the interviewer’s questions.
Alterations in mood are common and are of three main kinds. First, there may be symptoms of anxiety, depression, irritability, or euphoria. These can be clinically significant, but if such features are sufficiently prominent and sustained, the possibility of schizoaffective disorder or other affective psychosis should be considered. Secondly, there may be blunting (or flattening) of affect—that is, sustained emotional indifference or diminution of emotional response. Thirdly, there may be incongruity of affect, in which the expressed mood is not in keeping with the situation or with the patient’s own feelings.
Finally, we emphasize the variability of the clinical picture. Few patients experience all of the symptoms introduced above, while others already have features of the ‘chronic’ syndrome at first presentation. Moreover, the overall pattern and duration of features are also taken into account before making a diagnosis. Chronic schizophrenia
Although the positive symptoms of the acute syndrome may persist, the chronic syndrome is characterized by the negative symptoms of underactivity, lack of drive, social withdrawal, and emotional apathy. The vignette in Box 11.4 illustrates several of the negative features of what is sometimes called a ‘defect state’ or deficit syndrome. The most striking feature is diminished volition— that is, a lack of drive and initiative. Left to himself, the patient may remain inactive for long periods, or may engage in aimless and repeated activity. He withdraws from social encounters, and his social behaviour may deteriorate in ways that embarrass other people. Self-care may be poor, and the style of dress and presentation may be careful but somewhat inappropriate. Some patients collect and hoard objects, so that their surroundings become cluttered and dirty. Others break social conventions by talking intimately to strangers or shouting obscenities in public.
Speech is often abnormal, showing evidence of thought disorder of the kinds found in the acute syndrome described above. Affect is generally blunted and, when emotion is shown, it is incongruous or shallow. Hallucinations and delusions occur, but are by no means universal. They tend to be held with little emotional response. For example, patients may be convinced that they are being persecuted but show neither fear nor anger.
Various disorders of movement occur, including stereotypies, mannerisms and other catatonic symptoms, and dyskinesias (see below). The latter are primarily but not entirely due to antipsychotic medication. Cognitive impairment is common, if not universal, in chronic schizophrenia (see below), and, together with the negative symptoms, contributes to the low level of functioning and poor outcome that still bedevils chronic schizophrenia. However, the cognitive deficits are rarely of sufficient magnitude to be apparent unless detailed cognitive testing is undertaken, and this is rarely the case in clinical practice.
As with acute schizophrenia, the symptoms and signs of the chronic illness are variable. At any stage, positive symptoms may recur or become exacerbated; this may be in response to life events, or to discontinuation of medication.
Subtypes of schizophrenia
Schizophrenia is conventionally divided into several subtypes, based upon the predominant clinical features, especially during the acute phase(s) of the illness.
● Paranoid schizophrenia is the commonest form. It is
characterized by persecutory delusions, often systematized, and by persecutory auditory hallucinations.
Thought disorder and affective, catatonic, and negative symptoms are not prominent. Personality is relatively well preserved.
● In hebephrenic schizophrenia, also called disorganized
schizophrenia, thought disorder and affective symptoms are prominent. The mood is variable, with
behaviour often appearing silly and unpredictable.
Delusions and hallucinations are fleeting and not systematized. Mannerisms are common. Speech is rambling and incoherent, reflecting the thought disorder.
Negative symptoms occur early, and contribute to a
poor prognosis.
● In catatonic schizophrenia, the most striking features
are motor symptoms, as noted in Chapter 1, and
changes in activity that vary between excitement
and stupor. At times the person may appear to be
in a dream-like (oneiroid) state. Formerly common,
catatonic schizophrenia is now very rare, at least
in industrialized countries. Possible reasons for
this include a change in the nature of the illness,
improvements in treatment, or past misdiagnosis
of organic syndromes with catatonic symptoms. It
has also been argued that catatonia is a distinct syndrome (Fink et al., 2010) and this is reflected to a
degree in DSM-5 (see Box 11.6).
● Simple schizophrenia is characterized by the insidious
development of odd behaviour, social withdrawal,
and declining performance at work. Positive symptoms are not apparent. Given the limited utility of the
category and its history of abuse—for example, in the
detention of political dissidents in the former Soviet Union (‘sluggish schizophrenia’)—its use is now rare, and should be avoided.
● Undifferentiated schizophrenia is the term used for cases
that do not fit readily into any of the above subtypes,
or where there are equally prominent features of more
than one of them.
● Residual schizophrenia refers to a stage of chronic schizophrenia when, for at least a year, there have been
persistent negative symptoms but no recurrence of
positive symptoms.
Despite their widespread use, research has shown that these subsyndromes of schizophrenia are not reliable, stable over time, nor associated with clear differences in pathophysiology nor prognosis. For these reasons, they have been removed from DSM-5 (Tandon et al., 2013).
Other subclassifications of schizophrenia have also been proposed, intended to reflect biologically more valid entities. Two examples are given here: Liddle’s three subsyndromes, and Crow’s type I and type II schizophrenia.