Based on the above findings, we tested the synergistic effect of CSF IL-3, CSF sTREM2, and CSF p-tau/t-tau on the association between Aβ42 and cognitive decline: CSF Aβ42 → CSF IL-3 → sTREM2 → CSF p-tau/t-tau → cognitive change. The gene discussed is MAPT; the disease is Mental deterioration.