Toward a biochemical classification of depressive disorders, VI: Platelet MAO activity and clinical symptoms in depressed patients

The authors compared platelet monoamine oxidase (MAO) activity with clinical signs and symptoms in 32 patients with unipolar depressions. There was a statistically significant positive correlation between platelet MAO activity and scores on the Hamilton Rating Scale for Depression and between platelet MAO activity and specific clinical signs and symptoms in the spheres of depression, psychic anxiety, and somatic complaints. The clinical items found to be related to platelet MAO activity correspond to symptoms reported by other investigators to be associated with favorable responses to treatment with MAO inhibitors.