Rebecca C Stebbins1, Jessie K Edwards2, Brenda L Plassman3, Y Claire Yang4, Grace A Noppert5, Mary Haan6, Allison E Aiello7. 1. Carolina Population Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States; Social, Genetic, & Developmental Psychiatry CentreInstitute of Psychiatry, Psychology, and Neuroscience King's College London, London, United Kingdom. Electronic address: rebecca.stebbins@kcl.ac.uk. 2. Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States. 3. Departments of Psychiatry and Neurology, Duke University School of Medicine, Durham, NC, United States. 4. Carolina Population Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States; Department of Sociology, Lineberger Cancer Center University of North Carolina at Chapel Hill, United States. 5. Social Environment and Health, Survey Research Center, Institute for Social Research, University of Michigan, Ann Arbor, MI, United States. 6. Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, CA, United States. 7. Carolina Population Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States; Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States.
Abstract
BACKGROUND: The etiology of dementias and cognitive decline remain largely unknown. It is widely accepted that inflammation in the central nervous system plays a critical role in the pathogenesis of dementia. However, less is known about the role of the peripheral immune system and interactions with cortisol, though evidence suggests that these, too, may play a role. METHODS: Using data from 1337 participants aged 60+ years from the Sacramento Area Latino Study of Aging (observational cohort) we investigated variation in trajectories of cognitive decline by pathogen IgG and cytokine levels. Linear mixed effects models were used to examine the association between baseline Interleukin (IL)-6, C-reactive protein, tumor necrosis factor (TNF)-α, and five persistent pathogens' IgG response and trajectories of cognition over 10 years, and to examine interactions between immune biomarkers and cortisol. Stratified cumulative incidence functions were used to assess the relation between biomarkers and incident dementia. Inverse probability weights accounted for loss-to-follow-up and confounding. RESULTS: IL-6, TNF-α, and CMV IgG were statistically significantly associated with a higher log of Modified Mini-Mental State Examination errors (IL-6, β=0.0935 (95%CI: 0.055, 0.13), TNF-alpha β= 0.0944 (95%CI: 0.032, 0.157), and CMV, β= 0.0409 (95%CI: 0.013, 0.069)). Furthermore, cortisol interacted with HSV-1 and IL-6, and CRP for both cross-sectional cognitive function and rate of decline. No statistically significant relationship was detected between biomarkers and incidence of dementia. CONCLUSIONS: These findings support the theory that the peripheral immune system may play a role in cognitive decline but not incident dementia. Furthermore, they identify specific markers amenable for intervention for slowing decline.
BACKGROUND: The etiology of dementias and cognitive decline remain largely unknown. It is widely accepted that inflammation in the central nervous system plays a critical role in the pathogenesis of dementia. However, less is known about the role of the peripheral immune system and interactions with cortisol, though evidence suggests that these, too, may play a role. METHODS: Using data from 1337 participants aged 60+ years from the Sacramento Area Latino Study of Aging (observational cohort) we investigated variation in trajectories of cognitive decline by pathogen IgG and cytokine levels. Linear mixed effects models were used to examine the association between baseline Interleukin (IL)-6, C-reactive protein, tumor necrosis factor (TNF)-α, and five persistent pathogens' IgG response and trajectories of cognition over 10 years, and to examine interactions between immune biomarkers and cortisol. Stratified cumulative incidence functions were used to assess the relation between biomarkers and incident dementia. Inverse probability weights accounted for loss-to-follow-up and confounding. RESULTS: IL-6, TNF-α, and CMV IgG were statistically significantly associated with a higher log of Modified Mini-Mental State Examination errors (IL-6, β=0.0935 (95%CI: 0.055, 0.13), TNF-alpha β= 0.0944 (95%CI: 0.032, 0.157), and CMV, β= 0.0409 (95%CI: 0.013, 0.069)). Furthermore, cortisol interacted with HSV-1 and IL-6, and CRP for both cross-sectional cognitive function and rate of decline. No statistically significant relationship was detected between biomarkers and incidence of dementia. CONCLUSIONS: These findings support the theory that the peripheral immune system may play a role in cognitive decline but not incident dementia. Furthermore, they identify specific markers amenable for intervention for slowing decline.
Authors: H Akiyama; S Barger; S Barnum; B Bradt; J Bauer; G M Cole; N R Cooper; P Eikelenboom; M Emmerling; B L Fiebich; C E Finch; S Frautschy; W S Griffin; H Hampel; M Hull; G Landreth; L Lue; R Mrak; I R Mackenzie; P L McGeer; M K O'Banion; J Pachter; G Pasinetti; C Plata-Salaman; J Rogers; R Rydel; Y Shen; W Streit; R Strohmeyer; I Tooyoma; F L Van Muiswinkel; R Veerhuis; D Walker; S Webster; B Wegrzyniak; G Wenk; T Wyss-Coray Journal: Neurobiol Aging Date: 2000 May-Jun Impact factor: 4.673
Authors: Adina Zeki Al Hazzouri; Mary N Haan; John D Kalbfleisch; Sandro Galea; Lynda D Lisabeth; Allison E Aiello Journal: Am J Epidemiol Date: 2011-03-23 Impact factor: 4.897