Circulating Progenitor Cells is Linked to Cognitive Decline in Healthy Adults

Cognitive and cardiovascular disorders share many risk factors. Higher bone-marrow derived progenitor cells (PC) in blood are associated with lower rates of cardiovascular events but the association of PC with cognitive function is unclear. The objective of this study was to assess the association between PC and cognition in a sample of healthy adults enrolled in a cohort study.

A random sample of employees at Emory University and Georgia Institute of Technology were followed for 4 years and underwent yearly vascular and cognitive assessment (N = 430, mean age = 49.2 years, 70% women, and 27% African-American). Cognition was assessed using computerized versions of 15 cognitive tests and principal component analysis was used for deriving cognitive scores: executive function, memory and working memory. PC were defined as mononuclear cells with specific surface markers (7 phenotypes). Decreased cognition in a domain was defined as performing below the lowest quartile for the corresponding domain at baseline. Generalized estimating equations were used to investigate associations between PC and cognition.

Higher PC levels at baseline were associated with lower risk of cognitive decline in the executive and working memory domains during the follow-up period (P < 0.002 for all PC phenotypes). Further, the degree of decline in PC over the follow-up period was correlated with a corresponding decline in performances in all 3 cognitive domains over the same period (All P < 0.002).

Lower PC and greater yearly declines in PC are associated with greater cognitive decline. These findings suggest the role for PC in neurocognitive aging.