C-reactive protein is related to memory and medial temporal brain volume in older adults

Abstract

Recent research suggests a central role for inflammatory mechanisms in cognitive decline that may occur prior to evidence of neurodegeneration. Limited information exists, however, regarding the relationship between low-grade inflammation and cognitive function in healthy older adults. This study examined the relation between inflammation, verbal memory consolidation, and medial temporal lobe volumes in a cohort of older community-dwelling subjects. Subjects included 141 functionally intact, community dwelling older adults with detectable (n = 76) and undetectable (n= 65) levels of C-reactive protein. A verbal episodic memory measure was administered to all subjects, and measures of delayed recall and recognition memory were assessed. A semiautomated parcellation program was used to analyze structural MRI scans. On the episodic memory task, analysis of covariance revealed a significant CRP group by memory recall interaction, such that participants with detectable levels of CRP evidenced worse performance after a delay compared to those with undetectable levels of CRP. Individuals with detectable CRP also demonstrated lower performance on a measure of recognition memory. Imaging data demonstrated smaller left medial temporal lobe volumes in the detectable CRP group as compared with the undetectable CRP group. These findings underscore a potential role for inflammation in cognitive aging as a modifiable risk factor.

Brain morphology links systemic inflammation to cognitive function in midlife adults

“…These findings also replicate our earlier work, showing inverse associations of inflammatory markers with both global measures of gray matter volume and white matter integrity, and with regional gray matter volume of the hippocampus among healthy midlife adults (Gianaros et al, 2013; Marsland et al, 2008; Verstynen et al, 2013). Recent evidence shows a similar relationship of IL-6 and CRP with total gray matter and hippocampal volumes among older adults (Bettcher et al, 2012; Satizabal et al, 2012; Taki et al, 2013). Preclinical declines in brain size are widely thought to begin in the third decade of life, contributing to the cognitive declines that accompany healthy aging and risk for dementia (Burgmans et al, 2009; den Heijer et al, 2006; Driscoll et al, 2009; Raz et al, 2005; Walhovd et al, 2011).…”

“…Findings from studies of healthy older adults show inverse associations of markers of systemic inflammation with aspects of brain morphology that decline with age, including total brain volume (Jefferson et al, 2007), total gray matter volume (Satizabal et al, 2012), temporal lobe volume (Bettcher et al, 2012; Taki et al, 2013), hippocampal volume (Satizabal et al, 2012) and white matter integrity (Wersching et al, 2010). Our earlier work extended these findings to a midlife community sample, showing associations of higher IL-6 and CRP with lower total gray matter volume and white matter integrity throughout the brain, and with lower regional gray matter volume of the hippocampus and PFC (Gianaros et al, 2013; Marsland et al, 2008; Verstynen et al, 2013).…”

Cerebrospinal Fluid and Plasma Levels of Inflammation Differentially Relate to CNS Markers of Alzheimer’s Disease Pathology and Neuronal Damage

“…This study did not address recent history of infection or surgical procedures, which could impact both peripheral and central immune markers. Finally, based on our prior work demonstrating a lack of association between non-steroidal anti-inflammatory drugs [NSAIDs], circulating inflammatory markers, and clinical outcome measures in asymptomatic adults[53], we elected to not control for over the counter medications in our statistical models. Although we do not anticipate substantive differences in our cross-sectional findings based on NSAID use, it may be helpful for future longitudinal studies to address changes in NSAID use and dosing with respect to inflammation outcome measures.…”

Rates of Amyloid Imaging Positivity in Patients With Primary Progressive Aphasia

“…All patients and control individuals underwent whole-brain structural MRI using a 1.5T (Siemens Healthcare), 15,24 3T (Siemens Healthcare), 25 or 4T (Bruker Corporation and Siemens Healthcare) 26 scanner as previously described. We used voxel-based morphometry to study gray-matter atrophy patterns of svPPA (n = 24), nfvPPA (n = 28), and lvPPA (n = 25) groups (only including cases with typical amyloid imaging status) as well as each individual case with discordant amyloid imaging status and each PPAm case (eAppendix 2 in the Supplement).…”