Cerebrospinal fluid magnesium and calcium related to amine metabolites, diagnosis, and suicide attempts

Magnesium and calcium concentrations were measured in the cerebrospinal fluid (CSF) of 15 neurological controls and 41 psychiatric patients suffering from major depression (n = 16), schizophrenic disorder (n = 15), or adjustment disorder (n = 10). All subjects were women 19-67 years of age and free from drugs at the time of the study. CSF was evaluated for 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA), and cortisol (CS) levels, and all patients received a dexamethasone suppression test (DST) following lumbar puncture. CSF calcium levels did not differ among groups, although we found a trend toward higher mean levels in both depression and schizophrenia. By contrast, CSF magnesium was found to be significantly lower in both depression and adjustment disorder; if, however, patients who had made suicide attempts were excluded, the difference became insignificant. Patients who had made suicide attempts (by using either violent or nonviolent means) had significantly lower mean CSF magnesium level irrespective of the diagnosis. CSF calcium did not correlate with magnesium, 5-HIAA, HVA, CS, global severity, therapeutic response, or DST, but CSF magnesium correlated significantly with CSF 5-HIAA, especially after correcting for age and body height. Both variables seemed to be primarily related to recorded suicide attempts, but decreased magnesium was not limited to violent cases.