Antioxidant vitamin supplement use and risk of dementia or Alzheimer's disease in older adults
ABSTRACT To examine whether use of vitamins C or E alone or in combination was associated with lower incidence of dementia or Alzheimer's disease (AD).
Prospective cohort study.
Group Health Cooperative, Seattle, Washington.
Two thousand nine hundred sixty-nine participants aged 65 and older without cognitive impairment at baseline in the Adult Changes in Thought study.
Participants were followed biennially to identify incident dementia and AD diagnosed according to standard criteria. Participants were considered to be users of vitamins C or E if they self-reported use for at least 1 week during the month before baseline.
Over a mean follow-up+/-standard deviation of 5.5+/-2.7 years, 405 subjects developed dementia (289 developed AD). The use of vitamin E was not associated with dementia (adjusted hazard ratio (HR)=0.98, 95% confidence interval (CI)=0.77-1.25) or with AD (HR=1.04; 95% CI=0.78-1.39). No association was found between vitamin C alone (dementia: HR=0.90, 95% CI=0.71-1.13; AD: HR=0.95, 95% CI=0.72-1.25) or concurrent use of vitamin C and E (dementia: HR=0.93, 95% CI=0.72-1.20; AD: HR=1.00, 95% CI=0.73-1.35) and either outcome.
In this study, the use of supplemental vitamin E and C, alone or in combination, did not reduce risk of AD or overall dementia over 5.5 years of follow-up.
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ABSTRACT: Vitamin C is a pivotal antioxidant in the brain and has been reported to have numerous functions, including reactive oxygen species scavenging, neuromodulation, and involvement in angiogenesis. Absence of vitamin C in the brain has been shown to be detrimental to survival in newborn SVCT2(-/-) mice and perinatal deficiency have shown to reduce hippocampal volume and neuron number and cause decreased spatial cognition in guinea pigs, suggesting that maternal vitamin C deficiency could have severe consequences for the offspring. Furthermore, vitamin C deficiency has been proposed to play a role in age-related cognitive decline and in stroke risk and severity. The present review discusses the available literature on effects of vitamin C deficiency on the developing and aging brain with particular focus on in vivo experimentation and clinical studies.Nutrients 09/2014; 6(9):3818-3846. DOI:10.3390/nu6093818 · 3.15 Impact Factor
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