114 - References

References

112 The Maudsley® Prescribing Guidelines in Psychiatry CHAPTER 1 reduction in transition to psychosis or improvement in symptoms. From these RCTs, Cochrane concluded that omega-­3 fatty acids ‘may’ prevent transition to psychosis in the prodromal phase, but that the evidence is of low quality and this conclusion unconfirmed.39 The non-­randomised North American Prodromal Longitudinal Studies (NAPLS)40 found a positive correlation between functional improvement and frequency of dietary intake of EPA. The Program of Rehabilitation and Therapy (PORT) study41 found that young people at ultra-­high risk of psychosis who then developed the condition had lower dietary intake of omega-­3 and higher consumption of omega-­6 fatty acids compared with healthy controls. Taken together, these two RCTs (VHR and NEURAPRO) and two non-­ randomised trials (PORT and NAPLS) indicate a possible positive correlation between dietary omega-­3 and functional status, but more studies are required before a clinical benefit can be confirmed.42 A 2024 network meta-­analysis concluded that omega-­3 fatty acids are correlated with a lower risk of transition to psychosis compared with placebo, antipsychotics, mood stabilisers or antidepressants.43 However, this result was derived from only two studies (VHR and NEURAPRO) and just 194 participants. Overall PUFAs are no longer recommended for the treatment of residual symptoms of schizophrenia or for the prevention of transition to psychosis in young people at high risk.25,44–46 If used, careful assessment of response is important and fish oils should be withdrawn if no effect is observed after 3 months’ treatment, unless required for their beneficial metabolic effects. Summary recommendations – fish oils (PUFAs) ■ ■Patients at high risk of first-episode psychosis: ■ ■Not recommended. If used, suggest EPA 700mg/day. ■ ■Residual symptoms of multi-­episode schizophrenia (added to antipsychotic): ■ ■Not recommended. If used, suggest dose of EPA 2g/day. References

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