Personality traits and monoamine oxidase activity in platelets in depressed patients

Personality characteristics and platelet monoamine oxidase (MAO) activity have been assessed in 143 depressed patients of both sexes (60 males and 83 females) in the age range 21-65 years (mean age 44.8 +/- 12.8, SD), the personality inventory being completed by the patients when recovered, or at least markedly improved from the depressive disorder. In line with previous studies, a significant negative correlation between MAO activity and the variables, impulsivity and monotony avoidance, was found in the whole series. A significant negative correlation between MAO activities and the traits reflecting verbal aggression and irritability was also found. A separate analysis showed that those correlations hold true for female but not for male patients.