Decreased frontal white-matter integrity in abstinent methamphetamine abusers.
This study explored differences in frontal white-matter (WM) integrity between methamphetamine (MA) abusers and healthy comparison subjects using diffusion tensor imaging (DTI). Fractional anisotropy (FA) values, which indicate WM integrity, were calculated for regions-of-interest in frontal WM on diffusion tensor images of 32 MA abusers and 30 healthy comparison subjects. Frontal executive functions were also assessed by the Wisconsin Card Sorting test (WCST). MA abusers had significantly lower FA values in bilateral frontal WM at the anterior commissure-posterior commissure (AC-PC) plane and the right frontal WM 5 mm above the AC-PC plane relative to healthy comparison subjects. MA abusers had more total, perseveration and non-perseveration errors in the WCST relative to healthy comparison subjects. FA values of the right frontal WM 5 mm above the AC-PC plane negatively correlated with the number of total and non-perseveration errors in the WCST in MA abusers. In the sub-analysis for gender differences, lower FA values in frontal WM and more errors in the WCST were found only in male MA abusers, not in female MA abusers, relative to comparison subjects of the respective gender. We report that frontal WM integrity of MA abusers is compromised. This finding may also be related to impairment in frontal executive function. In addition, the neurotoxic effect of MA on frontal WM may be less prominent in women than in men, possibly due to oestrogen's neuroprotective effect.
Chung
Ain
A
Interdisciplinary Program in Brain Science, Seoul National University, Seoul, Korea.
Lyoo
In Kyoon
IK
Kim
Seog Ju
SJ
Hwang
Jaeuk
J
Bae
Soojeong C
SC
Sung
Young Hoon
YH
Sim
Minyoung E
ME
Song
In Chan
IC
Kim
Jihyun
J
Chang
Kee Hyun
KH
Renshaw
Perry F
PF
D000328:Adult; D019969:Amphetamine-Related Disorders / Q000473:pathology* / Q000523:psychology; D016880:Anisotropy; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008694:Methamphetamine; D009483:Neuropsychological Tests; D017397:Prefrontal Cortex / Q000473:pathology*; D011569:Psychiatric Status Rating Scales; D012727:Sex Characteristics; D015813:Substance Abuse Detection
D008694:Methamphetamine