Retinal function as a marker for cell membrane omega–3 fatty acid depletion in schizophrenia: a pilot study

Background: There is a growing body of evidence that abnormalities of the cell membrane, particularly depletion of n–3 essential fatty acids (EFA), are found in patients suffering from schizophrenia. These fatty acids particularly Docosohexaenoic acid (DHA) are found in particularly high concentrations in the photoreceptor cells of the retina and abnormalities of light sensitivity have been reported in patients with schizophrenia. Animal studies have demonstrated that reduced EFA levels are associated with changes in the electrophysiological response of the retina to light as measured by the electroretinogram (ERG). Methods: We measured the ERG of 9 patients with schizophrenia and 9 age and sex matched control subjects. All but one of the patients was medicated. Results: Schizophrenic subjects had significantly reduced a–wave amplitudes on the ERG when compared with control subjects and the a–wave amplitude was independent of the dose of antipsychotic agents being taken. The a–wave of the ERG is thought to reflect activity of the photoreceptor cells. Conclusions: These findings support the hypothesis that patients with schizophrenia have abnormalities of photoreceptor function, which may be a result of reduced levels of n–3 EFA in the cell membrane.