Objective Depression might be a prodromal stage of dementia. Many factors contribute to the etiology of depression and dementia, being inflammation one of those. The present work measured and analyzed immune molecules involved in the innate immunity on cluster of differentiation 14 (CD14+) monocytes trying to investigate any relationship among late‐onset depression (LOD) and Alzheimer's disease (AD). Methods Immune molecules were evaluated in monocytes of AD, LOD patients, and controls using flow cytometry. Results Interestingly, interleukin 1 beta (IL‐1β) expressing CD14+ monocytes were increased in AD patients compared with controls. LOD presented intermediate frequency of CD14+ monocytes expressing IL‐1β between controls and AD patients. Conclusion Results suggest that an increased frequency of CD14+ monocytes expressing IL‐1β level could be a stage marker related to the pathophysiology of dementia process between normal aging and AD. Copyright © 2013 John Wiley & Sons, Ltd.