The NEURAPRO Biomarker Analysis: Long-Chain Omega-3 Fatty Acids Improve 6-Month and 12-Month Outcomes in Youths at Ultra-High Risk for Psychosis

Background: NEURAPRO was a multicenter, placebo-controlled trial of long-chain omega-3 polyunsaturated fatty acids (n-3 PUFAs) (fish oil) in 304 individuals at ultra-high risk for psychotic disorders. The study failed to show benefits of n-3 PUFAs over placebo. Although the randomized controlled trial design is placed at the top of the evidence hierarchy, this methodology has limitations in fish oil randomized controlled trials, as not only is the test agent present in the intervention group, but also n-3 fats are present in the diet and the body tissue of all participants. Methods: Analysis of biomarker data (eicosapentaenoic acid [EPA], docosahexaenoic acid [DHA], n-3 index, EPA+DHA) collected as part of NEURAPRO was conducted on 218 participants with longitudinal biomarker data to determine if n-3 PUFAs measured in erythrocytes at baseline and month 6 predicted clinical outcomes. Results: Increases of the n-3 index, EPA, and DHA predicted less severe psychopathology and better functioning at both follow-up time points. Higher baseline levels and increases of n-3 index also predicted overall clinical improvement at month 6 (n-3 index baseline: adjusted odds ratio [95% confidence interval (CI)] = 1.79 [1.30–2.48]; n-3 PUFA increase: adjusted odds ratio [95% CI] = 1.43 [1.16–1.76]) and at month 12 (n-3 index baseline: adjusted odds ratio [95% CI] = 2.60 [1.71–3.97]; n-3 PUFA increase: adjusted odds ratio [95% CI] = 1.36 [1.06–1.74]). Conclusions: These data suggest that n-3 PUFAs can exert therapeutic effects in ultra-high-risk individuals. This finding has implications for early intervention and treatment guidelines, as n-3 PUFA supplementation can easily and safely be used in a wide variety of settings, from primary care to specialist services.