title: Early life socioeconomic position and immune response to persistent infections among elderly Latinos.
abstract: Persistent infections, such as cytomegalovirus (CMV), herpes simplex virus-1 (HSV-1), Helicobacter pylori (H. pylori), and Toxoplasma gondii (T. gondii), are common in the U.S. but their prevalence varies by socioeconomic status. It is unclear if early or later life socioeconomic position (SEP) is a more salient driver of disparities in immune control of these infections. Using data from the Sacramento Area Latino Study on Aging, we examined whether early or later life SEP was the strongest predictor of immune control later in life by contrasting two life course models, the critical period model and the chain of risk model. Early life SEP was measured as a latent variable, derived from parental education and occupation, and food availability. Indicators for SEP in later life included education level and occupation. Individuals were categorized by immune response to each pathogen (seronegative, low, medium and high) with increasing immune response representing poorer immune control. Cumulative immune response was estimated using a latent profile analysis with higher total immune response representing poorer immune control. Structural equation models were used to examine direct, indirect and total effects of early life SEP on each infection and cumulative immune response, controlling for age and gender. The direct effect of early life SEP on immune response was not statistically significant for the infections or cumulative immune response. Higher early life SEP was associated with lower immune response for T. gondii, H. pylori and cumulative immune response through pathways mediated by later life SEP. For CMV, higher early life SEP was both directly associated and partially mediated by later life SEP. No association was found between SEP and HSV-1. Findings from this study support a chain of risk model, whereby early life SEP acts through later life SEP to affect immune response to persistent infections in older age.
authors.affiliation: Epidemiology Branch, National Institute of Environmental Health Sciences, 111 T.W. Alexander Dr., P.O. Box 12233, MD A3-05, Research Triangle Park, NC 27709, United States. Electronic address: helen.meier@nih.gov.
authors.forename: Helen C S
authors.initials: HCS
authors.lastname: Meier
authors.affiliation: Department of Epidemiology and Biostatistics, University of California San Francisco, 550 15th Street, San Francisco, CA 94158, United States. Electronic address: mary.haan@ucsf.edu.
authors.forename: Mary N
authors.initials: MN
authors.lastname: Haan
authors.affiliation: Center for Social Epidemiology and Population Health, Department of Epidemiology, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109, United States. Electronic address: cmendes@umich.edu.
authors.forename: Carlos F
authors.initials: CF
authors.lastname: Mendes de Leon
authors.affiliation: Joseph J. Zilber School of Public Health, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, WI 53201, United States. Electronic address: simaneka@uwm.edu.
authors.forename: Amanda M
authors.initials: AM
authors.lastname: Simanek
authors.affiliation: Department of Epidemiology and Biostatistics, CUNY School of Public Health, Hunter College, City University of New York, 2180 Third Ave., New York, NY 10035, United States. Electronic address: jdowd@hunter.cuny.edu.
authors.forename: Jennifer B
authors.initials: JB
authors.lastname: Dowd
authors.affiliation: Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, 135 Dauer Dr. 2101B McGavran-Greenberg Hall, CB 7435, Chapel Hill, NC 27599, United States. Electronic address: aaiello@email.unc.edu.
authors.forename: Allison E
authors.initials: AE
authors.lastname: Aiello
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000208:ethnology / Q000276:immunology*; D002140:California / Q000453:epidemiology / Q000208:ethnology; D003141:Communicable Diseases / Q000453:epidemiology*; D003586:Cytomegalovirus Infections / Q000453:epidemiology; D005260:Female; D016481:Helicobacter Infections / Q000453:epidemiology; D006561:Herpes Simplex / Q000453:epidemiology; D006630:Hispanic or Latino / Q000706:statistics & numerical data*; D006801:Humans; D007111:Immunity, Cellular; D008297:Male; D008875:Middle Aged; D012923:Social Class; D014123:Toxoplasmosis / Q000453:epidemiology
keywords: Latino health; Life course epidemiology; Persistent infections; Socioeconomic position