Homocysteine levels are associated with hippocampus volume in type 2 diabetic patients.
BACKGROUND
Elevated total plasma homocysteine (tHcy) levels are associated with cognitive dysfunction, in which changes in the hippocampus plausibly play a pivotal role. We tested the hypothesis that elevated tHcy levels are correlated with hippocampus volume and insulin resistance in nondementia patients with type 2 diabetes.


METHODS
The study included 43 nondementia patients with type 2 diabetes, who were divided into two groups: a high tHcy group (age: 65 ± 8 years, mean ± standard deviation, n = 16) and a normal tHcy group (64 ± 9 years, n = 27). Hippocampus volume was quantified with a computer-assisted analysis using a magnetic resonance imaging (MRI) voxel-based specific regional analysis system developed for the study of Alzheimer's disease (VSRAD), which yields a Z-score as the end point for the assessment of hippocampal volume. Results  The Z-score was higher in the high tHcy group compared to the normal tHcy group (P < 0·0001). The fasting plasma glucose (P < 0·01) and insulin (P < 0·0001) concentrations and the homoeostasis model assessment (HOMA) index (P < 0·0001) were higher in the high tHcy group than in the normal tHcy group. Multiple regression analysis showed that the main factors that influenced tHcy levels may be the Z-score and the HOMA index.


CONCLUSIONS
Our results indicate that the elevated levels of tHcy in Japanese nondementia patients with type 2 diabetes are characterised by hippocampal atrophy and insulin resistance and that the Z-score and HOMA index may be the primary factors that influence tHcy levels.
Department of Neurosurgery, Faculty of Medicine, Oita University, Oita, Japan. simomura@oita-u.ac.jp
Tsuyoshi
T
Shimomura
Futoshi
F
Anan
Takayuki
T
Masaki
Yoshikazu
Y
Umeno
Nobuoki
N
Eshima
Tetsunori
T
Saikawa
Hironobu
H
Yoshimatsu
Minoru
M
Fujiki
Hidenori
H
Kobayashi
D000368:Aged; D001931:Brain Mapping / Q000379:methods; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000473:pathology / Q000523:psychology; D005260:Female; D006624:Hippocampus / Q000473:pathology*; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests
D006710:Homocysteine