Schizoaffective disorder was first described in the 1930s. This psychiatric condition has features of both schizophrenia and mood disorders, e.g. depression. Questions have been raised about whether it truly exists as a disease entity, although the term is still in common use by psychiatrists.^1,2

The cause is unknown. Various factors have been mooted, including genetic³, nutritional, viral, prenatal and metabolic (involving neurotransmitter dysfunction).⁴

Epidemiology

Schizoaffective disorder is less common than schizophrenia - there are no figures on the incidence and prevalence in the United Kingdom.

Schizoaffective manic patients have been reported to comprise 3-5% of all patients admitted to typical psychiatric hospital units.

The condition commonly presents in early adulthood and women are more often affected.

Diagnosis⁵

• Schizoaffective disorder occurs when, during the same illness, there is major depressive, manic or a mixed episode. This occurs along with the symptoms of schizophrenia.
• Delusions or hallucinations need to be present for at least two weeks when the mood symptoms are not present.
• Symptoms of mood disturbance are present for a significant length of the illness.
• The disturbance is not due to other causes, e.g. organic illness, substance misuse, medication (see 'Differential diagnosis', below).

The schizoaffective illness can be described as:

1. Bipolar type - when a manic or a mixed episode occurs.
2. Depressive type - the illness has mainly depressive episodes.

Presentation

This can be divided into major depressive episode, manic episode, mixed episode and schizophrenia.⁵

Differential diagnosis

It is important to ascertain that the disorder is not caused by any underlying process. Main groups of differentials include:

• Substance misuse, e.g. cannabis.
• Organic illness, e.g. hypothyroidism, delirium.
• Medication side-effects.
• For a depressive episode, it is necessary to ensure that it cannot be explained by recent life events, e.g. recent bereavement or loss of employment.
• Other psychiatric illness, e.g. dementia, delusional disorder.

Investigations

This will mainly be to rule out underlying causes and may include:

• Baseline bloods: FBC, renal and liver function, TFTs, HIV test.
• Urine or plasma toxicology.
• CXR to exclude pneumonia in the elderly.
• Other imaging if clinically indicated, e.g. patients with abnormal neurology may require CT or MRI scanning.

Associated problems

Patients affected by schizoaffective disorder can also have a number of other problems. These can include:

• Learning difficulties.
• Abnormal personality, e.g. antisocial or dependent.
• Psychosis.

Complications

• Poor social integration and function.
• Self-neglect.
• Difficulties with relationships.
• Substance misuse, e.g. alcohol.
• Suicidal behaviour.
• Homicidal thoughts.

Management⁴

Urgent hospital admission should be arranged for patients who are thought to be a threat to themselves or others, or who are too disabled to care for themselves.

Community services may be vital in keeping patients out of hospital or in managing the step-down into the community after hospital discharge. Specialist services which may be required include community psychiatric nursing and occupational therapy as well as more pragmatic support such as transport to and from hospital appointments, pharmacy delivery services and help in managing domestic and financial affairs.

There are few large trials that have specifically studied the drug treatment of schizoaffective disorder and there are no consensus guidelines. Treatment is based largely on the treatment of schizophrenia.¹ Antipsychotics are the mainstay of treatment, sometimes combined with psychological therapies.

Treatments can be divided as:

• Treatment of an acute exacerbation of schizoaffective disorder - antipsychotics are useful and it may be that atypical antipsychotics have some qualities superior to typical antipsychotics, e.g. risperidone or olanzapine.
• Long-term treatment of schizoaffective disorder - this involves the use of antipsychotics with psychological treatments. Antipsychotics improve patients with schizoaffective disorder, being more efficacious in those with bipolar type. Atypical antipsychotics may be more effective in schizoaffective disorders but more research is required here. Clozapine is sometimes used in resistant cases.
• Treatment of ongoing depressive symptoms in schizoaffective disorder - in this situation a trial of antidepressants is warranted and these may need to continue for longer periods of time. Sertraline or fluoxetine are often used. Occasionally, electroconvulsive therapy may be required.
• Mood stabilisers such as lithium may be useful in the bipolar type. Carbamazepine and valproic acid are other drugs in this category which have been used with some good results.

Psychological treatments involve - cognitive behavioural therapy, family interventions, counselling, art therapy and supportive psychotherapy. This is similar to the treatment of schizophrenia. The National Institute for Health and Clinical Excellence (NICE) in fact includes schizoaffective disorder as one of the 'negative symptoms' of schizophrenia and recommends psychological treatment accordingly.⁶

Prognosis

The bipolar type of schizoaffective disorder has a better prognosis than the depressive type, as the latter usually results in long-term mood disturbance.

Document references

1. Kantrowitz JT, Citrome L; Schizoaffective disorder: a review of current research themes and pharmacological CNS Drugs. 2011 Apr 1;25(4):317-31. doi: 10.2165/11587630-000000000-00000. [abstract]
2. Jager M, Haack S, Becker T, et al; Schizoaffective disorder-an ongoing challenge for psychiatric nosology. Eur Psychiatry. 2011 Apr;26(3):159-65. Epub 2010 Jun 19. [abstract]
3. Hamshere ML, Green EK, Jones IR, et al; Genetic utility of broadly defined bipolar schizoaffective disorder as a Br J Psychiatry. 2009 Jul;195(1):23-9. [abstract]
4. Brannon G; Schizoaffective Disorder, Medscape, September 2010
5. DSM-IV Criteria for Schizoaffective disorder - diagnostic criteria
6. Schizophrenia, NICE Clinical Guideline (March 2009); Core interventions in the treatment and management of schizophrenia in primary and secondary care

Acknowledgements