Resumen de Associations Between Serum Inflammatory Markers and Hippocampal Volume in a Community Sample
Mike F. Schmidt, Kevin B. Freeman, Beverly G. Windham, Michael E. Griswold, Iftikhar J. Kullo, Stephen T. Turner, Thomas H. Mosley Jr.
Objectives To quantify associations between inflammatory biomarkers and hippocampal volume (HV) and to examine effect modification according to sex, race, and age.
Design Cross-sectional analyses using generalized estimating equations to account for familial clustering; standardized β-coefficients adjusted for age, sex, race, and education.
Setting Community cohorts in Jackson, Mississippi and Rochester, Minnesota.
Participants The Genetic Epidemiology Network of Arteriopathy study.
Measurements C-reactive protein (CRP), interleukin-6 (IL-6), and soluble tumor necrosis factor receptors 1 (sTNFR-1) and 2 (sTNFR-2) from peripheral blood were measured in a sample of 773 non-Hispanic whites (61% women, aged 60.2 ± 9.8) and 514 African Americans (70% women, aged 63.9 ± 8.1) who also underwent brain magnetic resonance imaging. Biomarkers were standardized and compared according to sex, race and age with HV.
Results In the full sample, higher sTNFR-1 and sTNFR-2 were associated with smaller HV. Each standard deviation (SD) increase in sTNFR-1 was associated with 59.1 mm3 (95% confidence interval (CI) = −101.4 to −16.7 mm3) smaller HV and each SD increase in sTNFR-2 associated with 48.8 mm3 (95% CI = −92.2 to −5.3 mm3) smaller HV. Relationships were stronger for sTNFR-2 in men (HV = −116.6 mm3 for each SD increase, 95% CI = −201.0 to −32.1) than women (HV = −26.0 per SD increase, 95% CI = −72.4–20.5) and sTNFR-1 in non-Hispanic whites (HV = −84.7 mm3 per SD increase, 95% CI = −142.2 to −27.1) than African Americans (HV = −14.1 mm3 per SD increase, 95% CI = −78.3–50.1). Associations between IL-6 or CRP and HV were not supported.
Conclusion Higher levels of sTNFRs were associated cross-sectionally with smaller hippocampi. Longitudinal data are needed to determine whether these biomarkers may help to identify risk of late-life cognitive impairment.
