Total homocysteine and cognitive decline in a community-based sample of elderly subjects - The Rotterdam Study

Homocysteine has been associated with an increased risk of cardiovascular d isease. Cardiovascular diseases have been related to cognitive decline. The authors investigated the association of homocysteine with concurrent cogni tive impairment and subsequent cognitive decline in a random sample of 702 community-dwelling respondents aged 55 years or over to the prospective Rot terdam Study in 1990-1994. Multiple logistic regression was used to calcula te odds ratios and 95 percent confidence intervals for the association betw een total homocysteine levels and cognitive impairment (Mini-Mental State E xamination (MMSE) score <26) and cognitive decline (drop in MMSE score of > 1 point/year). Mean duration of follow-up was 2.7 years. After adjustment f or age, sex, and education, there was no relation between total homocystein e and cognitive impairment (highest vs. lowest tertile: odds ratio (OR) = 1 .30, 95% confidence interval (CI): 0.50, 3.38) or cognitive decline (middle vs. lowest tertile, OR = 1.14, 95% CI: 0.67, 1.93; highest vs. lowest tert ile: OR = 0.91, 95% CI: 0.52, 1.58), Subjects who were lost to follow-up du e to death or nonresponse had slightly higher age-adjusted homocysteine lev els and lower MMSE scores at baseline. Sensitivity analyses showed that sel ective loss to follow-up was not a likely explanation for the absence of an association in the participants. Although a relation between homocysteine and reduced cognitive function is biologically plausible, this study sugges ts no such association in a community-based sample of the elderly.