Catechol-O-methyl transferase activity in patients with depressive illness and anxiety states.

Erythrocyte catechol-O-methyl transferase (COMT) activity was studied in 65 patients with depressive illness and anxiety states. A hypothesis that measurement of this enzyme might have some value as an aid to diagnosis and as an index of clinical recovery has not been confirmed. In patients with endogenous depression, agitated subjects had COMT levels significantly higher than normal (P less than .01) and retarded subjects had levels significantly lower than normal (P less than .02). These observations are congruent with some reports of high and low urinary MHPG excretion in patients with depression. Further data correlating COMT assays with catecholamine metabolites in depressed patients may reveal homogeneous biochemical subgroups which could serve as a guide to rational therapy.