title: Urinary 8-hydroxy-2-deoxyguanosine and cognitive function in Puerto Rican adults.
abstract: DNA oxidative stress has been suggested as an important pathogenic mechanism in cognitive impairment and dementia. With baseline data collected from 2004 to 2008, the authors examined whether urinary 8-hydroxy-2-deoxyguanosine (8-OHdG), a biomarker of global DNA oxidation, was associated with cognitive function in a sample of 1,003 Puerto Rican adults, aged 45-75 years, living in Boston, Massachusetts, and the surrounding area. Cognitive function was measured by using a battery of 7 tests: the Mini-Mental State Examination, word list learning, digit span, clock drawing and figure copying, Stroop, and verbal fluency tests. The primary outcome was a global cognitive score, averaging standardized scores across all cognitive tests. A higher 8-OHdG concentration was significantly associated with lower global cognitive scores, after adjustment for age, education, status of the gene for apolipoprotein E (APOE), and other covariates (P(trend) = 0.01). The difference in the global score, comparing participants in the 2 extreme 8-OHdG quartiles, was -0.11 (95% confidence interval: -0.20, -0.02), which was equivalent to accelerating cognitive aging by about 4 years, as observed in this population. Prospective studies are needed to elucidate whether elevated urinary 8-OHdG concentrations can predict the rate of cognitive decline and incident dementia.
authors.affiliation: Department of Nutrition, Harvard University School of Public Health, Boston, Massachusetts 02115, USA. xiang.gao@channing.harvard.edu
authors.forename: Xiang
authors.initials: X
authors.lastname: Gao
authors.forename: Chao-Qiang
authors.initials: CQ
authors.lastname: Lai
authors.forename: Tammy
authors.initials: T
authors.lastname: Scott
authors.forename: Jian
authors.initials: J
authors.lastname: Shen
authors.forename: Tianxi
authors.initials: T
authors.lastname: Cai
authors.forename: Jose M
authors.initials: JM
authors.lastname: Ordovas
authors.forename: Katherine L
authors.initials: KL
authors.lastname: Tucker
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000368:Aged; D000911:Antibodies, Monoclonal; D001057:Apolipoproteins E / Q000235:genetics; D003072:Cognition Disorders / Q000175:diagnosis / Q000208:ethnology* / Q000652:urine*; D003704:Dementia / Q000175:diagnosis / Q000208:ethnology / Q000652:urine; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000652:urine; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008404:Massachusetts / Q000453:epidemiology; D008875:Middle Aged; D009483:Neuropsychological Tests; D018384:Oxidative Stress / Q000235:genetics; D015995:Prevalence; D011647:Puerto Rico / Q000208:ethnology; D012720:Severity of Illness Index
chemical_list: D000911:Antibodies, Monoclonal; D001057:Apolipoproteins E; D000080242:8-Hydroxy-2'-Deoxyguanosine; D003849:Deoxyguanosine