TNF and Alzheimer disease: In addition, previous studies have revealed associations between the serum levels of proinflammatory cytokines such as IL-1b, IL-6, and TNF alpha, which all increase the risk of dementia and AD.9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31.