Abnormal cerebral blood flow in methamphetamine abusers assessed by brain perfusion single emission computed tomography

Introduction: Amphetamines are central nervous system (CNS) stimulant substances and amphetamine abuse is considered a growing problem in our country. Previous studies revealed destructive effects of amphetamines on metabolism, perfusion and structure of brain. The aim of current study was evaluating regional cerebral blood flow (rCBF) disturbances in methamphetamine (MA) abusers using brain perfusion SPECT. Methods: This case control study was carried out on 15 MA abusers and 10 healthy volunteers. All 15 MA abusers had a history of MA abuse for at least one year, positive qualitative urinary test for amphetamine. All cases were substance dependent based on Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) criteria. Patients with opioid and other substance abuse except nicotine and caffeine, positive history of head trauma, loss of consciousness more than 30 minutes and also pregnant women were excluded. All subjects underwent brain perfusion Single-photon emission computed tomography (SPECT). Results: Of 15 MA users 11 and 4 cases were males and females respectively. Mean age was 42/46±12.08 (range: 22-65) years old. Mean age of control group was 39.56±10.10 (range: 25-63) years old. All MA abusers were currently on using MA. Mean dose of MA use was 0.7 gram per day and mean duration of consumption was 4.86 (1-12) years. Significant differences were observed in scan results (normal or abnormal scan) between two groups (p˂0.05). Of all 15 MA abusers, global decreased tracer uptake was observed in 4 patients (26.7%), global decrease uptake except for the cerebellum was detected in 6 cases (40%), and decreased tracer uptake in fronto-temporal lobes was observed in 2 cases (13.3%), decreased uptake was detected only in the temporal lobe in 2 patients (13.3%) and in temporo-occipital lobes in one case (6.7%). In patients group, decrease in perfusion was more prominent in right frontal, superior frontal and parietal lobes compared with left hemisphere. SPM (Statistical Parametric Mapping) analysis showed significant difference in rCBF between MA abusers and normal volunteers throughout the cerebral cortex with nonhomogeneous decreased tracer uptake. Conclusion: In this study, we showed that amphetamine abuse can induce diffuse and nonhomogeneous disorders of brain perfusion which was more prominent in the right hemisphere.