At Wave 4, in univariate and multivariable analyses, adjusted for Wave 4 covariates age and sex (Model 1) and additionally adjusted for education, BMI, ApoE ε4 status, alcohol use, smoking, physical activity score, diabetes, hypertension, stroke, PPI use, depression medication and antibiotic use, Mediterranean diet score, and fiber intake (model 2), stool type was not associated with GCS (all p trend ≥ 0.59) (Supporting Table 1). The gene discussed is APOE; the disease is major depressive disorder.