Psychotic disorders such as schizophrenia and schizoaffective disorder are devastating disorders that usually require chronic care and impact individuals and their family members greatly in terms of morbidity and mortality.  Research has helped to identify those who may be at greatest risk for developing psychotic disorders.  Strategies to prevent psychotic disorders would alleviate suffering and have great public health significance.

Amminger and colleagues conducted a double-blind, placebo-controlled trial of omega-3 fatty acids for the prevention of progression of psychotic disorders in a population at risk.   Participants were identified as high risk for the onset of a psychotic disorder if they were between the ages of 13-25, and met one or more of the criteria for a group at high risk for the development of a psychotic disorder.  The groups at high risk included: 1) those with attenuated psychotic symptoms, 2) those who had experienced transient psychosis (resolution without antipsychotic medication), and 3) those with trait plus state risk factors (i.e., having schizotypal personality disorder or a first degree relative with a psychotic disorder, and a significant decrease in functioning within the past year).

Exclusion criteria included a diagnosis of a psychotic disorder or mania, substance-induced psychotic disorder, acute suicidal or aggressive behavior, neurological disorder, mental retardation, previous treatment with an antipsychotic or mood stabilizer for more than one week.

81 patients were randomized to omega-3 fatty acids (eicosapentaenoic acid 700 mg per day, and docosahexaenoic acid 480 mg per day, for a total of 1180 mg per day) or placebo for 12 weeks.   The primary outcome was conversion to a psychotic disorder, using severity thresholds or the PANSS (Positive and Negative Syndrome Scale), and included minimum scores for hallucinations, delusions or conceptual disorganization.  The Structured Clinical Interview for DSM-IV was used to assess diagnoses at baseline and at 12-month follow-up.

Of the 38 assigned to omega-3 fatty acids, 2/38 progressed to develop a psychotic disorder (N=1 with paranoid schizophrenia and N=1 with schizophreniform disorder).  Of those randomized to placebo, 11/38 progressed to have a psychotic disorder (N=8 with schizophrenia, N=1 with schizophreniform disorder, N=1 with schizoaffective disorder, N=1 with bipolar disorder).  Erythrocyte essential fatty acid ratios were used to assess adherence.

This study suggests that a nutritional supplement with established health benefits may prevent progression of psychotic disorders in individuals at high risk or who are experiencing prodromal illness.  In consideration of the suffering that psychotic disorders cause, this research suggests that a low-risk strategy may help prevent or delay the onset of severe mental illness.  More research is needed to determine the role of omega-3 fatty acids in the prevention of illness progression and onset.  The implications that a non-toxic nutritional supplement could offset severe illness is exciting and deserves further study.

Marlene Freeman, MD

Amminger GP, Schäfer MR, Papageorgiou K, Klier CM, Cotton SM, Harrigan SM, Mackinnon A, McGorry PD, & Berger GE. Long-chain omega-3 fatty acids for indicated prevention of psychotic disorders: a randomized, placebo-controlled trial. Arch Gen Psychiatry. 2010 Feb;67(2):146-54.