Predicting the future course of psychotic illness

A psychotic episode can be a one-off event or an ongoing illness, but it’s currently difficult to predict. wrangler/Shutterstock

Psychotic illness is a relatively rare but often severe form of mental illness, affecting around one in 100 people at some point in their lives. It most commonly begins in adolescence and early adulthood, but onset can occur later during adulthood and even in the advanced years.

People with a psychotic illness may have a genetic predisposition, but not via a single gene. Multiple genes appear to be involved, as well as environmental factors such as stress, illicit drug use and social factors.

Methods of diagnosing psychotic illness haven’t changed in the past 15 to 20 years. Psychiatrists still rely on observing symptoms, then make informed guesses about the best course of treatment.

But emerging tools may offer a more sophisticated way of diagnosing psychotic illness, predicting the future course of the disease and providing early and specific treatment.

Symptoms and severity

People with psychotic illness can appear paranoid and may perceive their environment, and even friends and family, as hostile.

Signs of psychotic illness include abnormal sensory perception (such as visual hallucinations), changes in mood, disturbed thinking, reduced motivation, and a decline in function at work or school or University. Sleep problems can also occur.

Experience of psychotic illness varies from person to person but tends to follow one of four general courses. The first is the person has only one episode during their lifetime, with a full recovery afterwards.

The second course of illness includes multiple episodes of psychosis during the person’s lifetime, but they fully recover and go back to normal life between those episodes. These people usually need regular treatment.

In the third form, the multiple episodes of psychosis lead to progressive decline in day-to-day function. They don’t fully recover between single episodes, and worsen over time.

Finally, the most severe form of the illness is where the first episode of the disease leads to a severe decline in daily function, and the constant presence of severe signs and symptoms that require intensive treatment.

Problems diagnosing the disease

When the first signs and symptoms occur, psychiatrists cannot determine with enough certainty what type of illness course will likely take place, and what type of treatment should be provided and which treatments are unnecessary. This means treatment and interventions are reactive rather than preventive.

Unlike physical illnesses, we can’t rely on blood tests, brain scans or other biological tests. As a consequence of this lack of diagnostic accuracy, our field purely relies purely on observation.

But there is growing evidence that individual illness progression is dependent on a wide range of factors, including social, demographic, clinical, psychological and biological factors.

Towards a more sophisticated approach

My research team has developed a potential alternative to diagnosing and treating patients with severe mental illness, and psychosis in particular.

Our model integrates a range of diagnostic factors including clinical symptoms, cognitive abilities (memory, concentration, attention), MRI scans of the brain’s structure (to determine abnormal brain structure and function & loss of brain volume in circumscribed brain areas), and biomarkers (inflammatory biomarkers, neurotrophic biomarkers) in the patient’s blood, each of which play a specific role in the development and course of the illness.

When we use these factors individually, the prediction is usually poor. But when they’re taken together and are integrated in a meaningful way using appropriate prediction modelling as apply these in our research unit, then the likelihood with which the course of illness can be predicted increases significantly.

It may also help determine the patient’s treatment needs early and more specifically. Patients who are likely to progress to severe illness may be offered treatment earlier, for instance.

And those who are unlikely to develop severe illness may avoid unnecessary treatment – and the severe side effects.

Next steps in research

Our proposed approach would require a change in clinical practice. Clinicians would need to obtain a range of clinical, psychological and biological data from their patients in order to reach meaningful clinical conclusions and predictions rather than continue the pure trial-and-error approach. Collaboration between clinicians and specialist centres would be necessary to determine the disease trajectory.

But we’re not quite there, yet. We are currently re-analysing original data of previous studies in psychotic disorders and of ongoing research to show that our model works with currently available patient data. We are also testing our model on other groups of diagnoses, such as depression.

Should this approach prove to be valid, feasible and practicable after further rigorous testing and refinement, it could radically change clinical practice. We’re hoping it will one day help patients change the course of their illness and their lives for the better.

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