Increased hippocampal, thalamus and amygdala volume in long‐term lithium‐treated bipolar I disorder patients compared with unmedicated patients and healthy subjects

Objective Magnetic resonance imaging (MRI) studies in bipolar I disorder (BD‐I) suggest that lithium is associated with increased volumes of cortico‐limbic structures. However, more rigorous control of confounding factors is needed to obtain further support for this hypothesis. The aim of the present study was to assess differences in brain volumes among long‐term lithium‐treated BD‐I patients, unmedicated BD‐I patients, and healthy controls. Methods This was a cross‐sectional study with 32 euthymic BD‐I patients (16 on lithium monotherapy for a mean of 180 months, and 16 receiving no medication for at least the 2 months prior to the study) and 20 healthy controls. Patients were euthymic (Hamilton Depression Rating Scale [HDRS]