Role of inflammation in the socioeconomic inequalities of neurocognitive disorders

Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved..

BACKGROUND: Socioeconomic position has been shown to be associated with inflammation. However, little is known about the role of inflammation in socioeconomic inequalities in relation to neurocognitive disorders in later life and the potential underlying inflammatory mechanisms. This study has used longitudinal data to investigate the mediation effects of inflammation in the relationship between socioeconomic position and neurocognitive disorders in older adults.

METHODS: Using data from the English Longitudinal Study of Ageing (ELSA, n = 4,815), we ascertained neurocognitive disorders using a recognised consensus criterion and included the following categories: (1) No Cognitive Impairment (NOCI) (2) Cognitive Impairment No Dementia (CIND) and (3) Dementia. We examined whether socioeconomic position (education, occupation, and wealth) measured in 2008/09 was associated with neurocognitive disorders measured in 2018/19. Mediation analyses were carried out to investigate the role of inflammatory markers [C-Reactive Protein (CRP), plasma fibrinogen and white blood cells (WBC)] in the association between socioeconomic inequalities and subsequent neurocognitive disorders. Sensitivity analyses were conducted to assess the mediating role of lifestyle behaviours and body mass index (BMI).

RESULTS: Higher education, occupation and wealth were longitudinally associated with a lower likelihood of cognitive impairment and dementia. WBC mediated the association between latent socioeconomic position and CIND [β = -0.037 (CI: -0.06 to -0.01)], but not the association with dementia. Indirect effects were attenuated but remained significant when other mediators, such as lifestyle behaviours and BMI were considered. In a separate analysis accounting for main confounders, CRP and fibrinogen mediated the association between education and CIND, all three inflammatory biomarkers mediated the association of occupation and CIND, while WBC mediated the association between wealth and CIND.

CONCLUSION: These findings emphasise that socioeconomic inequalities in mid and later life could contribute to the prevalence of neurocognitive disorders in later life. Our results provide some evidence for the biological embedding of WBC in the association between socioeconomic inequalities and cognitive impairment via elevated inflammation. Future studies should explore other plausible biological mechanisms.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:113

Enthalten in:

Brain, behavior, and immunity - 113(2023) vom: 24. Okt., Seite 203-211

Sprache:

Englisch

Beteiligte Personen:

Gireesh, Aswathikutty [VerfasserIn]
Sacker, Amanda [VerfasserIn]
McMunn, Anne [VerfasserIn]
Cadar, Dorina [VerfasserIn]

Links:

Volltext

Themen:

9001-32-5
9007-41-4
C-Reactive Protein
C-reactive protein
Fibrinogen
Inflammation
Journal Article
Neurocognitive disorders
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Socioeconomic inequalities
White blood cells

Anmerkungen:

Date Completed 04.09.2023

Date Revised 05.09.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.bbi.2023.07.013

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM359949959