Schizophrenia is a debilitating illness that affects an estimated 25 million people worldwide. People with the condition can experience a huge amount of disability (both social, physical and psychological), but we know that early intervention can help reduce the duration of the illness and prevent further episodes of relapse.
People with schizophrenia usually experience a prodromal period before the full blown psychotic illness appears (McGlashan, 2003). This period generally lasts 1-3 years and is characterised by:
- Non-specific behavioural and psychological symptoms
- A deterioration in function
- Positive symptoms that gradually taper off
- Brief limited intermittent psychotic symptoms (BLIPS)
Research has shown that 22-44% of people at ultra high risk will go on to develop schizophrenia.
Early intervention in schizophrenia has two specific elements that are not found in usual care:
- Early detection
- Phase-specific treatment (psychological, social or physical treatment that focuses on early stages of the illness)
There are a number of effective treatments for people at different stages of the illness, but this new systematic review focuses on which interventions can be targeted at people who are at high risk of psychosis, with a view to preventing or delaying the transition.
A Cochrane review on early interventions for psychosis was published in 2011 (Marshall, 2011), but only includes studies that were published up to 2009. This is a fast moving field and this more recent review includes a number of newer trials that have come out in the last couple of years.
The reviewers searched a wide range of databases for studies published up to November 2011. They targeted randomised controlled trials (RCTs) comparing any psychological, pharmacological, nutritional, or combined intervention with usual services or another treatment.
They excluded studies with participants who had a formal diagnosis of schizophrenia or bipolar disorder. Studies were assessed for bias by two independent authors using the Cochrane risk of bias tool.
The primary outcome was transition to psychosis. Secondary outcomes were symptoms of psychosis, depression, mania, quality of life, weight and discontinuation.
They included 11 RCTs in the final analysis, that’s a total of 1,246 patients (mean age 21 years, 57% male).
- Cognitive behavioural therapy (CBT) reduced transition to psychosis at 12 months (risk ratio 0.54 (95% confidence interval 0.34 to 0.86); risk difference −0.07 (−0.14 to −0.01)
- Omega-3 fatty acids and integrated psychotherapy were also associated with reductions in transition to psychosis at 12 months, but the evidence for these treatments was quite poor
- The review found no evidence that antipsychotic drugs can delay or prevent transition to psychosis. This should be considered an absence of evidence rather than evidence of absence, but nonetheless an important finding in this group, particularly given the side effects of antipsychotics
- Psychotherapies were also associated with significant side effects, with about 10% of participants in such treatment groups deteriorating. The authors highlighted that future trials of talking treatments should report adverse effects
The reviewers concluded:
Schizophrenia and the psychoses are highly disabling, recurrent, and most often lifelong conditions with substantial costs to the patient, their family, and the state; arguably greater than almost all other psychiatric conditions. The possible prevention of transition to psychosis and schizophrenia for people at high risk clearly represents an important finding.
Therefore, further research should be undertaken in the form of a large, multicentre trial of combined family and individual CBT for high risk groups, evaluating both benefits and potential harms (for example, possible increased stigma).
In the meantime, the use of these psychological treatments now represents the most appropriate intervention available for helping people avert what could be a personal, social, and financial catastrophe.
Stafford MR, Jackson H, Mayo-Wilson E, Morrison AP, Kendall T. Early interventions to prevent psychosis: systematic review and meta-analysis. BMJ. 2013 Jan 18;346:f185. doi: 10.1136/bmj.f185.
McGlashan TH. Commentary: Progress, issues, and implications of prodromal research: an inside view. Schizophr Bull 2003;29:851-8. [PubMed abstract]
Marshall M, Rathbone J. Early intervention for psychosis. Cochrane Database of Systematic Reviews 2011, Issue 6. Art. No.: CD004718. DOI: 10.1002/14651858.CD004718.pub3.