Skin Barrier Function and Cognition among Older Adults.

Age-associated declines in the skin barrier function result in increased exposure to cutaneous microbes and toxins and lead to chronic, low-grade systemic inflammation ( Hu et al., 2017 Hu L. Mauro T.M. Dang E. Man G. Zhang J. Lee D. et al. Epidermal dysfunction leads to an age-associated increase in levels of serum inflammatory cytokines. J Invest Dermatol. 2017; 137: 1277-1285 Abstract Full Text Full Text PDF PubMed Scopus (67) Google Scholar ). Chronic inflammation is now thought to be an important mechanism in the onset and progression of dementia, and multiple chronic inflammatory states have been associated with subsequent cognitive impairment ( Heppner et al., 2015 Heppner F.L. Ransohoff R.M. Becher B. Immune attack: the role of inflammation in Alzheimer disease. Nat Rev Neurosci. 2015; 16: 358-372 Crossref PubMed Scopus (1379) Google Scholar ; Wen et al., 2022 Wen S. Elias P.M. Wakefield J.S. Mauro T.M. Man M.Q. The link between cutaneous inflammation and cognitive impairment. J Eur Acad Dermatol Venereol. 2022; 36: 1705-1712 Crossref PubMed Scopus (6) Google Scholar ). Epidemiologic studies of eczema (atopic dermatitis) support the rationale for investigating skin barrier decline and cognition: eczema is a pathogenic example of skin barrier dysfunction; eczema severity has been associated with cognitive function ( Silverberg et al., 2020 Silverberg J.I. Lei D. Yousaf M. Janmohamed S.R. Vakharia P.P. Chopra R. et al. Association of atopic dermatitis severity with cognitive function in adults. J Am Acad Dermatol. 2020; 83: 1349-1359 Abstract Full Text Full Text PDF PubMed Scopus (27) Google Scholar ), and moderate to severe eczema among older adults has been associated with an increased risk of dementia in multiple longitudinal studies ( Eriksson et al., 2008 Eriksson U.K. Gatz M. Dickman P.W. Fratiglioni L. Pedersen N.L. Asthma, eczema, rhinitis and the risk for dementia. Dement Geriatr Cogn Disord. 2008; 25: 148-156 Crossref PubMed Scopus (35) Google Scholar ; Magyari et al., 2019 Magyari A. Lam V. Wehner M.R. Margolis D. Langan S. Abuabara K. Atopic eczema in adulthood and the risk of dementia: a population-based cohort study. J Invest Dermatol. 2019; 139: S33 Abstract Full Text Full Text PDF Google Scholar ; Pan et al., 2021 Pan T.L. Bai Y.M. Cheng C.M. Tsai S.J. Tsai C.F. Su T.P. et al. Atopic dermatitis and dementia risk: A nationwide longitudinal study. Ann Allergy Asthma Immunol. 2021; 127: 200-205 Abstract Full Text Full Text PDF PubMed Scopus (11) Google Scholar ). Our objective was to examine the association between skin barrier function, as measured by water loss and tape stripping, and cognition.