2.1. Study population

The study protocol was approved by the institutional research review board at each study site, and every participant provided written informed consent. Participants were enrolled in the Mayo Clinic Bipolar Biobank at the Mayo Clinic, Rochester, MN, the Lindner Center of Hope/University of Cincinnati, OH, the University of Minnesota, Minneapolis, MN, Universidad Autónoma de Nuevo León, Mexico and Universidad de los Andes, Chile (Frye et al., 2015b). A subset of the total sample completed self-report measures to assess diet quality and, for participants from Mayo Clinic site, complementary metabolic data was acquired through review of electronic health records (EHR) (Supplementary Table 1) (Cuellar-Barboza et al., 2020; Frye et al., 2015a; Romo-Nava et al., 2020). Criteria for participation in the Bipolar Biobank included: a) a diagnosis of types I and II bipolar disorder or schizoaffective disorder, bipolar type confirmed with the Structured Clinical Interview for DSM-IV (SCID-IV); b) no current suicidal ideation or psychosis; and c) age 18 through 80 years (Frye et al., 2015a).