| Summary: | This thesis explored the hypothesis that cytomegalovirus (CMV) infection and its reactivation may be a shared mechanism linking psychosocial and behavioral factors with the age-associated decline in immunity, known as immunosenescence. The first empirical chapter (Chapter 3) showed that psychological stress factors were positively associated with CMV reactivation, as measured by increased CMV-specific IgG antibodies (CMV-IgG) among those infected, while socioeconomic and lifestyle factors were associated with CMV infection rates. Chapter 4 investigated personality traits and revealed that increased neuroticism predicted elevated odds of CMV infection and higher conscientiousness was associated with lower CMV-IgG levels. Chapter 5 demonstrated that more frequent physical activity was associated with lower levels of highly-differentiated T-cells, but this association was reduced to non-significance by adjustment for CMV infection. Chapter 6 showed that dysregulated glucose metabolism, measured as higher glycated hemoglobin levels, was associated with increased highly-differentiated T-cells in CMV-infected individuals. Furthermore, hyperglycemia interacted with CMV infection for a further increased accumulation of these cells. In sum, these results suggest that CMV and psychosocial and behavioral factors co-determine the progression of immunosenescence, and that CMV reactivation may reflect imbalance among these factors. Thus, CMV reactivation is proposed as a common pathway in psychobiological relationships with immunosenescence.
|
|---|
