Two proteins were decreased in both Aβ- MCI and AD compared to Aβ- controls, including TNF-related activation-induced cytokine (TRANCE; d = − 0.4 in Aβ- MCI; d = − 0.3 in AD; q < 0.05) and brevican (d = − 0.29 in Aβ- MCI; d = − 0.2 in AD; q < 0.05); see Fig. 2b and Table 3. Here, TNFSF11 is linked to Alzheimer disease.