Suchttherapie 2015; 16 - P_08
DOI: 10.1055/s-0035-1557702

Structural and functional brain changes in chronic cocaine users

M Herdener 1, F Esposito 2, J Hänggi 3, K Preller 4, P Stämpfli 5, M Kirschner 1, E Seifritz 6, BB Quednow 4
  • 1Center for Addictive Disorders, Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Switzerland
  • 2Department of Medicine and Surgery, University of Salerno, Italy
  • 3Institute of Psychology, University of Zurich, Switzerland
  • 4Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Switzerland
  • 5MR Center, Psychiatric Hospital, University of Zurich, Zurich Switzerland
  • 6Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich Switzerland

Introduction: Cocaine is considered as one of the most harmful drugs because of the potentially detrimental psychological, physical, and social consequences of its regular use. Psychological changes associated with cocaine use comprise cognitive impairments that have been observed in dependent and recreational cocaine users (CUs). Moreover, cocaine use has been suggested to promote a premature ageing of the brain. However, at least the observed cognitive changes in CUs co-vary with changes in recent cocaine consumption, pointing to some reversibility of these cocaine-induced cognitive impairments.

Method: Here, we investigated changes in brain structure of CUs and its association with cocaine use measures. In addition, we were interested in concomitant changes in resting state brain metabolism. To this end, we used structural magnetic resonance tomography to assess whole-brain cortical thickness (CT) as the most accurate measure of cortical atrophy in a relatively pure sample of dependent and recreational CUs (n = 20) in comparison to healthy controls (n = 25). Moreover, we evaluated the impact of recent cocaine use on CT.

In addition to structural measures, we applied arterial spin labeled perfusion magnetic resonance imaging (ASL MRI) to measure cerebral blood flow (CBF) at rest in the same subjects. CBF as measured by ASL MRI is tightly linked with local brain metabolism and is considered as a sensitive functional marker of neurodegenerative processes.

Results: We found significant reduced CT in CUs in inferior temporal cortices, right precuneus, and left frontal and parietal cortex. Moreover, we observed diminished perfusion in left frontal and parietal cortex in CUs within the same regions where we observed cortical thinning. Our data also indicate a correlation between hypoperfusion in left parietal cortex and impaired working memory performance in CUs. In CUs, both measures of cortical thinning and hypoperfusion are correlated with the amount of cocaine used during the past 6 months but not with cumulative lifetime use of cocaine.

Discussion: Our findings suggest that CUs show specific and concomitant structural and perfusion abnormalities indicative of neurodegenerative processes in frontoparietal cortices that are, at least in part, correlated with a decline in working memory performance. Interestingly, the observed changes in structure and perfusion are associated with parameters of recent cocaine use but not with lifetime cocaine consumption. These results indicate a potential reversibility of the observed cocaine-related brain changes, a perspective that has important therapeutic implications and will be further investigated in future longitudinal studies.