Pharmacopsychiatry 2005; 38 - A032
DOI: 10.1055/s-2005-918654

3T-Spectroscopy in the hippocampus and cognitive status of lithium-treated euthymic bipolar patients

M Colla 1, F Schubert 2, J Heidenreich 3, F Seifert 2, M Bubner 1, M Bajbouj 1, I Heuser 1
  • 1Charité - Universitätsmedizin Berlin, Department of Psychiatry and Psychotherapy, Campus Benjamin Franklin, Berlin
  • 2Laboratory of Biomedical Optics and NMR-Measuring Techniques, Division of Medical Physics and Metrological Information Technology, Berlin, Germany, Berlin
  • 3Charité - Universitätsmedizin Berlin, Department of Radiology, Campus Benjamin Franklin, Berlin

Aims: while lithium is accepted as the most widely used mood-stabilizer in the treatment of bipolar disorders, and even discussed as a candidate drug against cognitive deterioration, the mechanism of its action and its effect on the cognitive status remains largely speculative.

Methods: twenty patients with bipolar disorder (age 36–68 y) were studied and having been medicated for 3–27 years with Li. Nineteen age, gender and education matched healthy controls were also examined. The MRS measurements were carried out with a 3-Tesla-scanner with compounds fitted with prior knowledge for frequency, linewidth and phase. Additionally, the whole group underwent a specific cognitive testing.

Results: in patients the concentration of Glu in the left, but not right, hippocampus voxel was positively correlated with Li concentration in serum which was confirmed for the amplitude ratios Glu/tCr and Glu/water. In addition we found a distinctive impairment in visuo-spatial tasks with a robust correlation of these variables in the right, but not left hippocampus and NAA.

Conclusion: the most noteworthy observation of Glu and its positive correlation with Li on chronic Li therapy supports earlier in vitro findings that the drug may amplify Glu release and inhibit synaptosomal Glu uptake. Beside this, NAA might be an excellent metabolic marker of monitoring cognitive processing.