RT Journal
A1 Machanic BI
T1 HIgh-dose b vitamin supplements and alzheimer disease
JF JAMA
JO JAMA
YR 2009
FD March 11
VO 301
IS 10
SP 1020
OP 1022
DO 10.1001/jama.2009.212
UL http://dx.doi.org/10.1001/jama.2009.212
AB 
Prior studies have shown a relationship between low cerebrospinal fluid folate levels in patients with AD compared with normal controls. Low levels of L-methyl folate and methyl B12 have correlated with increased risk of cognitive impairment.2 It is possible that the patients in the study by Aisen et al were too advanced beyond a potential time window for benefit from B vitamin intervention to see a beneficial result.