Gene set enrichment analysis (GSEA) using methylGSA revealed enrichment of mitogen-activated protein kinase signaling pathway (P = 0.002, adjusted P = 0.05) and Fc epsilon RI signaling pathway (P = 0.01, adjusted P = 0.14) for the rate of cognitive decline as measured by the slope of mPACCtrailsB (Additional file 2: Table 2A). The gene discussed is WNK2; the disease is Mental deterioration.