Association of C-reactive protein with mild cognitive impairment.
BACKGROUND
Inflammation is proposed to play a role in the development of Alzheimer's disease, and may also be involved in the pathogenesis of mild cognitive impairment (MCI). This study examined the association of inflammatory markers in serum or plasma with prevalent MCI and MCI subtypes in a population-based sample.


METHODS
Olmsted County, MN, residents aged 70-89 years on October 1, 2004, were evaluated using the Clinical Dementia Rating Scale, a neurological evaluation, and neuropsychological testing. Information ascertained for each participant was reviewed by an expert panel of neuropsychologists, physicians, and nurses, and a diagnosis of normal cognition, MCI, or dementia was made by consensus. C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis alpha (TNFalpha), and adiponectin were measured at baseline.


RESULTS
Among 313 subjects with MCI and 1570 cognitively normal subjects, a CRP level in the upper quartile (>3.3 mg/L) was significantly associated with MCI (odds ratio [OR], 1.42; 95% confidence interval [CI], 1.00-2.01) and with nonamnestic MCI (OR, 2.05; 95% CI, 1.12-3.78) after adjusting for age, sex, and years of education. However, there was no association with amnestic MCI (OR, 1.21; 95% CI, 0.81-1.82). No association was observed with the other inflammatory markers.


CONCLUSIONS
Plasma CRP is associated with prevalent MCI and with nonamnestic MCI in elderly, nondemented persons in a population-based setting. These findings suggest the involvement of inflammation in the pathogenesis of MCI.
Roberts
Rosebud O
RO
Division of Epidemiology, Department of Health Sciences Research, College of Medicine, Mayo Clinic, Rochester, MN, USA. roberts.rosebud@mayo.edu
Geda
Yonas E
YE
Knopman
David S
DS
Boeve
Bradley F
BF
Christianson
Teresa J H
TJ
Pankratz
V Shane
VS
Kullo
Iftikhar J
IJ
Tangalos
Eric G
EG
Ivnik
Robert J
RJ
Petersen
Ronald C
RC
D052242:Adiponectin / Q000097:blood*; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism*; D003072:Cognition Disorders / Q000097:blood* / Q000175:diagnosis / Q000523:psychology; D003430:Cross-Sectional Studies; D016207:Cytokines / Q000097:blood*; D003704:Dementia / Q000097:blood / Q000175:diagnosis; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D008297:Male; D008910:Minnesota; D009483:Neuropsychological Tests; D011795:Surveys and Questionnaires
D052242:Adiponectin; D015415:Biomarkers; D016207:Cytokines; D002097:C-Reactive Protein