Plasma magnesium in chronic schizophrenia. A preliminary report.

A group of 36 subjects, 20 chronic schizophrenic patients and 16 nonpsychotic mentally retarded patients were chosen at random from the chronic care wards of the Douglas Hospital to assess levels of magnesium, calcium and phosphorus. No significant differences were found between the two groups in calcium and phosphorus. However, the magnesium level was significantly lower (p less than 0.01) in the schizophrenic group than in the mentally retarded group. This difference reached a level of 0.001 significance when chronic female schizophrenic patients were compared to the female mentally retarded group. Hospitalization, diet and medication were excluded as possible etiological factors.