Cytomegalovirus (CMV) is ubiquitous and the incidence of human infection increases with age. CMV exacerbates immunosenescence and is associated with increased mortality and morbidity in older adults. Cognitive decline in older generations causes great personal and financial burden. Here, examination of the Lothian Birth Cohort (1936) establishes an association between higher CMV IgG tires and a decline in general cognitive ability. This work also further defines the influence of CMV and Epstein-Barr virus (EBV) infection upon immune repertoire.
Analysis of the 1000 Elders cohort in Birmingham demonstrates that CMV-and EBV-specific T cell responses remain stable over a period of ten years. However, CMV seronegative older adults display higher EBV viral loads compared to CMV seropositive individuals despite a similar frequency of EBV-specific T cell responses in both groups. In addition, CMV serostatus does not appear to influence the phenotype of EBV-specific T cell responses.
Collectively, this study defines an association between high CMV IgG titres and decreased cognitive ability in older adults and demonstrates differential control of EBV by CMV seropositive and negative adults. High EBV viral loads may impact negatively upon the health of older adults; this should be studied further in future work
