PPARA and rheumatoid arthritis: To focus on the key pathways of SZ, we selected six pathways (pathogenic Escherichia coli infection, rheumatoid arthritis, PPAR signaling pathway, bile secretion, GnRH signaling pathway, fat digestion, and absorption) that represent the common characteristics of SZ from 18 common pathways based on the enrichment scores of the pathways and the degree of association with the main symptoms of SZ.