TNF and Lewy body dementia: Further inconsistent findings, including no observable differences between disease-group participants and controls in peripheral IL-6 or other cytokines, have also been reported.53, 55 Greater peripheral levels of IL-6 have been associated with worse cognitive performance in both DLB and AD,48 49 56 while TNF-α concentrations were related to severity of neuropsychiatric symptoms in DLB.56