We further show higher levels of proteins related to soluble tumor necrosis factor receptor 1 are associated with reduced risk of conversion to dementia in the multi-centered (p = 0.027) and independent (p = 0.038) cohorts of people with mild cognitive impairment due to predicted Alzheimer’s disease, while higher soluble TREM2 levels associated with slower decline in the dementia stage of Alzheimer’s disease. Here, TNFRSF1A is linked to early-onset autosomal dominant Alzheimer disease.