Psychosis - diagnosis and management

What is Psychosis?

Psychosis occurs in a number of serious mental illnesses and not just schizophrenia - eg, depression, bipolar disorder (manic-depressive illness), puerperal psychosis and sometimes with drug and alcohol misuse. It can also occur in a number of neurological conditions and with drugs not associated with misuse.

Psychosis interferes with the ability to function and can be very debilitating. Disabling symptoms include delusions and hallucinations:

• A delusion is a false, fixed, strange, or irrational belief that is firmly held. The belief is not normally accepted by other members of the same culture or group. It is important to look at culture, especially with ethnic issues, to decide if strange beliefs are really psychotic. There are delusions of paranoia (plots against them), delusions of grandeur (exaggerated ideas of importance or identity) and somatic delusions (false belief in having a terminal illness).

• An hallucination is sensory perception (seeing, hearing, feeling, smelling) without an appropriate stimulus, like hearing voices when no one is talking. Not all hallucination suggests psychosis.

See the separate Delusions and hallucinations article.

How common is psychosis? (Epidemiology)

• About 0.5% of people aged 16 years or older in England receive a diagnosis of a psychotic disorder (schizophrenia, schizoaffective disorder, or affective psychosis) in the preceding year.¹

• An international study found the pooled incidence of all psychotic disorders was 26·6 per 100,000 person-years (95% CI 22·0-31·7).² Heterogeneity was high (I2 ≥98·5%). Men were at higher risk of all psychotic disorders (incidence rate ratio 1·44 [1·27-1·62]) and non-affective disorders (1·60 [1·44-1·77]) than women, but not affective psychotic disorders (0·87 [0·75-1·00]).

• UK studies suggest a higher prevalence of psychosis in the black and minority ethnic (BAME) rather than white population.³

Psychosis symptoms

Symptoms vary according to the condition but the doctor of first contact will need to address the following general issues:

• The patient is often brought to the doctor by a third party. This might be because the patient lacks insight but, more likely, because psychosis is a very distressing condition, both for the patient and for those around and a degree of support is required.

• Occasionally, the first contact may be with family members who have concerns about a member of their family. If the patient cannot be persuaded to come to the surgery, a home visit may be necessary.

• Where the patient may behave aggressively, consider a joint visit with an experienced community psychiatric nurse and/or the police.

Question the patient directly to discover the symptoms and to ascertain the degree of insight. The accompanying person may be extremely valuable in terms of giving history.

Follow the guidance for psychiatric assessment but history should cover the following ground (the accompanying person may be a very valuable source of information):

• What is the nature of the hallucination or delusion?

• What is the time span?

• Is there a recurring theme?

• Is there insight into it being unreal?

• Have there been any recent major life events?

• Is there a history of substance misuse (alcohol or drugs)?

• Does the patient's past behaviour suggest psychological vulnerability - eg, irritability, uneasiness, suspiciousness and withdrawn mood?

• Is there a family history of mental illness?

Whilst taking the history it is possible to make an assessment of the patient's mental state:¹

• Is there loss of touch with reality; are there delusions or a bewildered mood?

• Is thought or speech disorganised, abstract or vague?

• Is emotion normal and appropriate? Remember that such experiences will naturally cause extreme anxiety but are there inappropriate emotional outbursts?

• Is there excitement or confusion?

• Is there depression or suicidal ideation? Depression can cause psychosis and all forms of mental illness have a risk of suicide, not just depression. There are a number of forms of self-harm assessment.

Physical examination is unlikely to be rewarding in the younger patient but, in the older one, there may be physical signs of alcohol misuse, neurological features and/or other signs of systemic disease. Always look for evidence of poor personal hygiene or self-neglect.

For more information on the presentation of psychosis, see the separate articles listed under 'Differential diagnosis', below.

Investigations

Psychosis will usually require urgent referral to mental health services but there are some investigations that can be undertaken in the practice. The management of schizophrenia in primary care is well established but most doctors will want a specialist opinion at the outset.

Differential diagnoses suggest the following tests may be useful:

• Abnormal LFTs and macrocytosis on FBC are highly suggestive of alcohol misuse.⁴

• Serological tests for syphilis.⁵

• Screening for AIDS.

• Urine screen for recreational drugs. Light recreational use of cannabis can produce a positive test for the subsequent fortnight. Heavy and chronic use can produce a positive result for months after the last use.⁶

• CT brain scan could exclude a space-occupying lesion or cerebral atrophy if focal signs are present - but not routinely.

Differential diagnosis

The history should help to distinguish between schizophrenia, bipolar disorder and depression; history, however, can be misleading.

Treatment for psychosis^{1 7}

It is very important to recognise and manage a first episode of psychosis correctly, as delay in diagnosis may adversely affect prognosis. If there is an external cause like substance misuse this must be addressed. Remember that psychosis in substance misuse can be part of dual diagnosis.⁶ Family intervention is an evidence-based support programme available in many areas which helps to reduce the relapse rate of psychotic patients in both early and late stages.⁸

The National Institute for Health and Care Excellence (NICE) emphasises the need to treat all patients who have psychosis with respect throughout the whole care plan, including the experience of compulsory hospitalisation where necessary.⁹

Aims of treatment¹⁰

Prompt assessment
Admission to a psychiatric unit is often required at the outset. Compulsory admission and possibly enforced treatment under the Mental Health Act may be required. The condition is so distressing that some patients may go voluntarily. The family also tends to prefer the patient to be in a safe environment. See the separate Compulsory hospitalisation article.

In the initial management of a first episode of psychosis the GP's role will primarily be to make a presumptive diagnosis and arrange secondary care assessment. Occasionally the patient's behaviour will be such that it presents a threat to personal safety or the safety of others. In such circumstances the GP may be required to provide rapid tranquilisation.

Antipsychotic drugs¹¹

First-generation antipsychotic drugs

• First-generation antipsychotic drugs (also known as typical or conventional) act predominantly by blocking dopamine D2 receptors in the brain. They are more likely to cause a range of side-effects, particularly acute extrapyramidal symptoms and hyperprolactinaemia.

• First-generation antipsychotics include the phenothiazine derivatives (chlorpromazine hydrochloride, fluphenazine decanoate, levomepromazine, pericyazine, prochlorperazine, promazine hydrochloride, and trifluoperazine), the butyrophenones (benperidol and haloperidol), the thioxanthenes (flupentixol and zuclopenthixol), the diphenylbutylpiperidines (pimozide) and the substituted benzamides (sulpiride).

Second-generation antipsychotic drugs

• Second-generation antipsychotic drugs (also referred to as atypical) act on a range of receptors in comparison to first-generation antipsychotic drugs and are generally associated with a lower risk for acute extrapyramidal symptoms and tardive dyskinesia; the extent varies between individual drugs. However, second-generation antipsychotic drugs are associated with several other important adverse effects, such as weight gain and glucose intolerance.

• Second-generation antipsychotics include amisulpride, aripiprazole, asenapine, cariprazine, clozapine, lurasidone hydrochloride, olanzapine, paliperidone, quetiapine, and risperidone.

See also the leaflets on Schizophrenia, Bipolar disorder and Depression.

Prognosis

The outlook in patients with psychosis has improved, due to the policy of early intervention and improvements in drug treatment.

After pharmacological, psychological, and other interventions, many people experience regression or resolution of symptoms, although some negative symptoms may remain:¹

• It is estimated that 80% of people show some response to treatment within the first year.

• Only 20% of people will have no further psychotic episodes within the following five years.

• The most common course is initial improvement of symptoms with ongoing recurrent acute psychotic episodes or relapses over many years.

• It has been reported that around 15% of people experience persistent psychotic symptoms that are unresponsive to treatment two years after the acute episode. These people may require rehabilitation and support including help with activities of daily living.

Factors associated with a poor prognosis include:¹²

• Longer duration of untreated psychosis.

• Early or insidious onset of schizophrenia.

• Male sex.

• Negative symptoms.

• Family history of schizophrenia.

• Low IQ, low socio-economic status, or social isolation.

• Significant psychiatric history.

• Continued substance misuse.