In some cases, dementia appears to be associated with oxidative stress. A study published in the Archives of Gerontology and Geriatrics (2001; Suppl. 7:325–331) compared 30 adults aged 90–107 years with dementia to 32 cognitively healthy individuals of similar age. Men with dementia had higher levels of thiobarbituric acid–reactive substances and lower vitamin E levels—both markers of oxidative stress. This association was observed in men but not in women, suggesting possible sex-specific differences.
Additional population data support a role for antioxidant status. Research published in Neurobiology of Aging (2005;26[7]:987–994), involving 1,033 adults over age 65, found that lower blood levels of vitamin E were associated with a higher incidence of dementia.
Dietary patterns may also be relevant. A large twin study published in the American Journal of Geriatric Psychiatry (Vol. 18, Issue 5, pp. 413–420) followed 3,779 Swedish twins, 355 of whom developed dementia. Greater consumption of fruits and vegetables was associated with a reduced risk of dementia.
Finally, a study in Neurology (2000;54:1265–1272) examined 3,385 men aged 71–93 and found that supplementation with vitamins A and C was associated with a lower risk of vascular dementia. The protective effect was weaker for mixed dementia and was not observed for Alzheimer’s disease.
Taken together, these findings suggest that oxidative stress and antioxidant status may be relevant to certain forms of dementia—particularly vascular dementia—though effects appear to vary by sex and dementia subtype.
