Cerebral ischemia mediates the effect of serum uric acid on cognitive function.
OBJECTIVE
High normal concentrations of serum uric acid (UA) are associated with mild cognitive dysfunction and increased cerebral ischemia as indexed by white matter hyperintensity volumes. We hypothesized that individual differences in white matter hyperintensities mediate the association between UA and mild cognitive dysfunction.


METHODS
One hundred eighty community-dwelling adults aged 20 to 96 years completed neuropsychological testing, laboratory blood studies, and a brain MRI scan.


RESULTS
Serum UA was associated (P<0.05) with greater white matter hyperintensities and poorer working memory, processing speed, fluency, and verbal memory. Associations remained after controlling for age, sex, race, education, hypertension, diabetes, alcohol abuse, smoking, and body mass. Adding a term for white matter hyperintensity attenuated these associations such that UA no longer predicted cognitive performance.


CONCLUSIONS
Severity of cerebral ischemia might mediate the association between UA and cognitive dysfunction. Even mild elevations in UA appear to contribute to structural and functional brain changes.
Vannorsdall
Tracy D
TD
Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Jinnah
H A
HA
Gordon
Barry
B
Kraut
Michael
M
Schretlen
David J
DJ
D000328:Adult; D000368:Aged; D001921:Brain / Q000473:pathology*; D001929:Brain Edema / Q000209:etiology / Q000473:pathology; D002545:Brain Ischemia / Q000097:blood / Q000209:etiology* / Q000473:pathology; D003072:Cognition Disorders / Q000097:blood / Q000209:etiology*; D005260:Female; D006801:Humans; D033461:Hyperuricemia / Q000150:complications / Q000523:psychology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders / Q000097:blood / Q000209:etiology; D008875:Middle Aged; D009186:Myelin Sheath / Q000473:pathology; D014527:Uric Acid / Q000097:blood*; D014706:Verbal Learning
D014527:Uric Acid
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