A multi-national, multi-disciplinary Delphi consensus study on using omega-3 polyunsaturated fatty acids (n-3 PUFAs)...

Omega-3 polyunsaturated fatty acids (n-3 PUFAs) are recommended as an integrative treatment for major depressive disorder (MDD). In 2019, the International Society for Nutritional Psychiatry Research (ISNPR) developed the first practice guidelines for n-3 PUFA treatment of MDD. To strengthen these guidelines and enhance their clinical applicability, we synthesized the evidence and clinical experiences previously obtained through the Delphi methodology.

Nineteen statements covering five major domains in MDD treatment were formulated through internal meetings. Fourteen international experts were invited to participate in the web-based Delphi process that validated the statements. Likert scales were used, and consensus level was set at 7.0/10.0, with the equivocal level set at 5.1-6.9. The items with scores < 5.0 were allocated into a second round Delphi survey with inverse questions.

All panelists completed the survey. Sixteen statements reached consensus, and the statement "n-3 PUFAs are one of the potential adjunctive treatments for adult MDD" reached the highest agreement. "N-3 PUFAs are one of the potential monotherapies for adult MDD" instead scored lowest. Regarding "special populations," many items, reached high consensus despite sub-optimal supportive evidence.

The panelists had a specialized interest in n-3 PUFAs; focus was placed on clinical issues rather than on biological mechanisms.

The Delphi process helps bridge the gap between scientific evidence and clinical practice, supports certain uses of PUFA and identifies insufficiency in current evidence that merit future research.