Aetiology

Psychosis as a mental illness is usually diagnosed by psychiatrists based on the symptoms of the patient and is made according to the internationally recognised diagnostic systems. Other professions (such as clinical psychologists) can also give an initial diagnosis, refer patients and assist patients as well as their families. The process of diagnosis will include getting to know the patient in-depth as well as finding relevant information from their family members (i.e. medical history). Internationally recognised diagnostic systems currently include DSM-5 and ICD-10.

In general, if an individual is suspected to be suffering from psychosis, they can first seek advice from a general practitioner who would then advise them, if they need to be referred to a psychiatrist or a psychologist for further check-ups, assessment and treatment. Professionals may require the individual, his/her family members and friends to provide more relevant details; all information will be treated with the utmost confidentiality. Psychiatrists may also be able to schedule biological investigation such blood tests, X-rays or brain scans for identifying any biological causes of psychosis. Then a clear formulation of the condition of the individual patient will be formed and appropriate intervention plan for the individual will be designed. The intervention and further monitoring of the condition will involve multiple professionals.

Apart from main medical service, care for patients are supported by many other services in the communities in order to provide a comprehensive care to the patients and their family. Please click here if you are interested in learning more about other relevant services.

If the circumstance is urgent or serious, patient and family members can also visit the nearby A&E/Emergency department directly.

Scientists are yet to determine the causes of psychosis, however, it is agreed that it is brain disease, and studies indicate that the symptoms of psychosis could be due to the imbalance of dopamine, a neurotransmitter in the brain.

Is it genetic?
A family history of psychosis is associated with a higher likelihood of developing the disorder. However it is likely to be a polygenic condition.

Is it stress-related?
Most patients experience stressful events prior to the onset of psychosis (such as: marriage, emigration, school transferring, relationship break-up, unemployment, public examinations, domestic violence, loss of loved ones), however the relationship between stress and psychosis is not necessarily unidirectional, and it is possible for stressful events to be the products of prodromal symptoms experienced by the patient as their daily lives may have been affected by the symptoms.  

Is it drug-related?
Certain drugs such as ketamine and cocaine can induce psychosis symptoms temporarily. Research shows that long-term abuse of drugs such as cannabis, could lead to a higher chance of developing psychosis in the future, even though the user has stopped using the drugs.

Is it related to one's upbringing?
Some studies show that prenatal infection, malnutrition, obstetrics complications, childhood abuse or trauma could increase one’s chance of developing psychosis.

The above factors may affect dopamine activities in the brain, which is associated with psychosis. Scientists are still trying to understand the relationship between these factors and the brain activity and hence development of psychosis, and examining other potential factors that may increase the chance of one developing psychosis. The brain is a very complex organ and our understanding of its function and mechanisms is still rudimentary. More research will be needed to understand the brain and the mechanisms of developing psychosis.