Occipital cortical proton MRS at 4 Tesla in human moderate MDMA polydrug users

The recreational drug MDMA (3,4, methylenedioxymethamphetamine; sold under the street name of Ecstasy) is toxic to serotonergic axons in some animal models of MDMA administration. In humans, MDMA use is associated with alterations in markers of brain function that are pronounced in occipital cortex. Among neuroimaging methods, magnetic resonance spectroscopy (MRS) studies of brain metabolites N-acetylaspartate (NAA) and myoinositol (MI) at a field strength of 1.5 Tesla (T) reveal inconsistent results in MDMA users. Because higher field strength proton MRS has theoretical advantages over lower field strengths, we used proton MRS at 4.0 T to study absolute concentrations of occipital cortical NAA and MI in a cohort of moderate MDMA users (n = 9) versus non-MDMA using (n = 7) controls. Mean NAA in non-MDMA users was 10.47 mM (± 2.51), versus 9.83 mM (± 1.94) in MDMA users. Mean MI in non-MDMA users was 7.43 mM (± .68), versus 6.57 mM (± 1.59) in MDMA users. There were no statistical differences in absolute metabolite levels for NAA and MI in occipital cortex of MDMA users and controls. These findings are not supportive of MDMA-induced alterations in NAA or MI levels in this small sample of moderate MDMA users. Limitations to this study suggest caution in the interpretation of these results.