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Background: Anemia and red cell distribution width (RDW) have been linked to poor cognitive performance, pending studies of underlying mechanisms.Objective: We examined cross-sectional relationships of initial RDW status (v1), RDW change (δ), and anemia with brain structural magnetic resonance imaging (sMRI) markers, including global and cortical brain and hippocampal and white matter lesion (WML) volumes, 5-6 years later.Methods: Data were used from three prospective visits within the Healthy Aging in Neighborhoods of Diversity Across the Life Span (HANDLS) study with complete v1 (2004-2009) and v2 (2009-2013) exposures and ancillary sMRI data at vscan (2011-2015, n = 213, mean v1 to vscan time: 5.7 years). Multivariable-adjusted linear regression models were conducted, overall, by sex, by race, and within non-anemics, correcting for multiple testing with q-values.Results: In minimally adjusted models (socio-demographics and follow-up time), anemiav1 and RDWv1 were consistently associated with smaller bilateral hippocampal volumes overall, and among females (q < 0.05), without significant sex differences. RDWv1 was related to smaller select regional cortical brain gray and white matter volumes in hematological measure-adjusted models; anemiav1 was associated with larger WML volumes only among whites.Conclusion: In summary, baseline anemia and RDW were consistently associated with smaller bilateral hippocampal volumes, particularly among females, while anemia was linked to larger WML volume among Whites. In hematological measure-adjusted models, baseline RDW was linked to smaller regional gray and white matter volumes. Pending studies with sMRI repeats, randomized controlled trials are needed, demonstrating associations of anemia and elevated RDW with reduced brain volumes and cognitive dysfunction. [ABSTRACT FROM AUTHOR]

Functional magnetic resonance imaging (fMRI) was used to compare cortical nociceptive responses to painful contact heat in healthy young (ages 22–30, n= 7) and older (ages 56–75, n= 7) subjects. Compared to young subjects, older subjects had significantly smaller pain-related fMRI responses in anterior insula (aINS) ( P < 0.04), primary somatosensory cortex (S1) ( P= 0.03), and supplementary motor area ( P= 0.02). Gray matter volumes in S1 and aINS were significantly smaller for the older group ( P= 0.02 and 0.0001, respectively), suggesting reduced processing capacity in these regions that might account for smaller pain-related fMRI responses. [ABSTRACT FROM AUTHOR]