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Lithium and Increased Cortical Gray Matter—More Tissue or More Water?

      I read Bearden and colleagues’ “Greater Cortical Gray Matter Density in Lithium-Treated Patients with Bipolar Disorder” with great interest. I was hoping to learn that they had performed analyses to determine whether an increase in brain tissue water could have contributed to their finding increased cortical gray matter density in lithium-treated patients. However, like other investigators finding increased cortical thickness in bipolar subjects taking lithium (
      • Moore G.J.
      • Bebchuk J.M.
      • Wilds I.B.
      • Chen G.
      • Manji H.K.
      Lithium-induced increase in human brain grey matter.
      ,
      • Sassi R.B.
      • Nicoletti M.
      • Brambilla P.
      • Mallinger A.G.
      • Frank E.
      • Kupfer D.J.
      • et al.
      Increased gray matter volume in lithium-treated bipolar disorder patients.
      ), Bearden and colleagues did not report any data measuring gray matter water content. They briefly discussed a possible contribution of water and then dismissed it in favor of their hypothesized lithium-induced increase in neuropil. They reasoned that although “we cannot exclude the possibility that the observed gray matter differences in the lithium-treated group are related to osmotic effects of lithium leading to changes in water content in the brain, a purely osmotic action would be unlikely to be restricted to gray matter alone (
      • Sassi R.B.
      • Nicoletti M.
      • Brambilla P.
      • Mallinger A.G.
      • Frank E.
      • Kupfer D.J.
      • et al.
      Increased gray matter volume in lithium-treated bipolar disorder patients.
      ); the absence of any differences in white matter argues against this interpretation.” The Sassi and colleagues (2002) study cited used the same argument against a contribution of water, again, without providing any supporting data.
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      References

        • Moore G.J.
        • Bebchuk J.M.
        • Wilds I.B.
        • Chen G.
        • Manji H.K.
        Lithium-induced increase in human brain grey matter.
        Lancet. 2000; 356: 1241-1242
        • Sassi R.B.
        • Nicoletti M.
        • Brambilla P.
        • Mallinger A.G.
        • Frank E.
        • Kupfer D.J.
        • et al.
        Increased gray matter volume in lithium-treated bipolar disorder patients.
        Neurosci Lett. 2002; 329: 243-245
        • Phatak P.
        • Shaldivin A.
        • King L.S.
        • Shapiro P.
        • Regenold W.T.
        Lithium and inositol: Effects on brain water homeostasis in the rat.
        Psychopharmacology (Berl). 2006; 186: 41-47
        • Saul R.F.
        • Hamburger H.A.
        • Selhorst J.B.
        Pseudotumor cerebri secondary to lithium carbonate.
        JAMA. 1985; 253: 2869-2870

      Linked Article

      • Greater Cortical Gray Matter Density in Lithium-Treated Patients with Bipolar Disorder
        Biological PsychiatryVol. 62Issue 1
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          The neurobiological underpinnings of bipolar disorder are not well understood. Previous neuroimaging findings have been inconsistent; however, new methods for three-dimensional (3-D) computational image analysis may better characterize neuroanatomic changes than standard volumetric measures.
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      • Reply: Lithium and Increased Cortical Gray Matter—More Tissue or More Water?
        Biological PsychiatryVol. 63Issue 3
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          We thank Dr. Regenold for his interest and comment on our recent article, in which we identified significantly increased gray matter (GM) density, particularly within the bilateral cingulate and paralimbic cortices, in lithium-treated patients with bipolar disorder, relative to healthy control subjects (1). Dr. Regenold voices some disappointment that we did not determine whether an increase in brain tissue water might have contributed to our findings. Although GM increases might, in part, reflect expansion of neuropil content, unfortunately brain imaging cannot confirm which cellular changes are occurring in living patients.
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