CSF magnesium in affective disorder: Lack of correlation with clinical course of treatment

There has been recent renewed interest in the role of magnesium in affective disorder, particularly in the bipolar subtype. However, determinations of serum magnesium concentrations have not yielded consistent findings and little is known about cerebrospinal fluid (CSF) magnesium in these patients. We analyzed CSF magnesium levels from 173 medication-free patients with affective disorder (76 bipolar I, 54 bipolar II, and 43 unipolar) and 59 healthy volunteers. In addition, we examined CSF magnesium from 32 patients before and during carbamazepine treatment and 13 patients before and during lithium treatment. CSF magnesium levels varied significantly according to gender (with lower concentrations in women) but not with respect to age, diagnosis, mood state, or treatment with carbamazepine or lithium. An abnormality of magnesium in affective disorders, if it exists, is not readily detectable in CSF.