Metabolite alterations in basal ganglia associated with methamphetamine-related psychiatric symptoms. A proton MRS study.

Following the chronic use of methamphetamine, some individuals experience psychosis and anxiety. One reason may be the persistence of metabolite abnormalities in the brain of currently abstinent former methamphetamine users. In this study, N-acetylaspartate (NAA), creatine plus phosphocreatine (Cr+PCr), and choline-containing compound (Cho) levels were measured in the left and right basal ganglia using proton magnetic resonance spectroscopy (MRS) in 13 abstinent methamphetamine users and 11 healthy comparison subjects with no history of illicit drug use. The methamphetamine users showed a significantly reduced Cr+PCr/Cho ratio in the bilateral basal ganglia compared with the healthy comparison subjects. Furthermore, the reduction in the Cr+PCr/Cho ratio was significantly correlated with the duration of methamphetamine use and with the severity of residual psychiatric symptoms. NAA/Cho ratios in the bilateral basal ganglia did not significantly differ between methamphetamine users and comparison subjects. These findings suggest that protracted use of methamphetamine may cause metabolite alterations in the basal ganglia. Furthermore, residual psychiatric symptoms may be attributable to the metabolite alterations in the basal ganglia.