Investigation of Subtle Microstructural Changes in the Development of Long-Term Methamphetamine-Induced Psychosis: A Diffusion Tensor Imaging Study

Abstract

Introduction: Methamphetamine (METH) is an illicit psychostimulant that is widely abused in the world. METH abuse may lead to white matter injury and to a range of behavioral disorder and psychosis. The present study sought to assess subtle white matter microstructural change as well as psychosis in long-term METH dependence.

Methods: We recruited 42 METH users’ subject meeting DSM-5 criteria and 21 healthy controls. Psychotic signs were measured using the Positive and Negative Syndrome Scale (PANSS). We applied tract-based spatial statistics (TBSS) to investigate group differences in mean diffusivity, fractional anisotropy, axial and radial diffusivity, and their association with psychotic symptoms.

Results: This DTI study of whole brain white matter integrity based on TBSS and its relation with psychotic symptoms revealed two main findings in the METH group. (a) METH addicts had significantly lower FA and higher AD, RD, and MD in a wide range of white matter. (b) Subjects in the METH group had significantly higher PANSS total score, when compared to the control group.

Conclusion: METH addicts show subtle patterns of impaired white matter integrity of distinct Cerebral nerve pathways relative to controls. The results are further suggestive of neuronal tract based pathology playing a key role in psychotic symptoms in METH dependence.