Lifespan Socioeconomic Context Is Associated With Cytomegalovirus and Late-Differentiated CD8+ T and Natural Killer Cells: Initial Results in Older Adults

Abstract

Objective Lower socioeconomic status (SES) can accelerate immune aging; however, it is unknown whether and how lifespan socioeconomic context (SEC) —the relative wealth and quality of the communities an individual lives in across their lifespan— impacts immune aging. We examined the effects of childhood and adulthood SEC on late-differentiated immune cells and investigated the mediating and moderating role of cytomegalovirus (CMV), a key driver of immune aging. Methods Adults 60 years and older (N = 109) reported their addresses from birth to age 60, which were coded for county-level employment, education, and income to construct a latent SEC variable, averaged across ages 0-18 (childhood SEC) and 19-60 (adulthood SEC). Blood was drawn semiannually over 5 years for CMV serostatus and flow cytometry estimates of late-differentiated CD8+ T and natural killer (NK) cells. Models were adjusted for chronological age, time, gender, and individual SES (current income and education). Results Lower childhood SEC was associated with higher percentages of late-differentiated CD8+ T and NK cells via CMV seropositivity (indirect effects ps .015-.028). Additionally, an interaction between CMV serostatus and SEC on CD8+ T cell aging (p = .049) demonstrated that adulthood SEC was negatively associated with immune aging among CMV– but not CMV+ adults. Conclusions Beyond current SES, socioeconomic context related to immune aging in distinct patterns by lifespan phase. Lower childhood SEC importantly may influence who acquires CMV, which in turn, predicts higher levels of immune aging, whereas higher adulthood SEC was protective against immune aging among CMV– older adults. These initial results need to be explored in larger samples.