Platelet monoamine oxidase activity, ego strength, and neuroticism in soldiers with combat-related current posttraumatic stress disorder

Aim. To assess possible differences in platelet monoamino oxidase-B (MAO-B) activity ego strength, and neuroticism in combat-experienced soldiers with or without current posttraumatic stress disorder (PTSD). Method. The soldiers with current PTSD (N=36) and a control group of 34 hea lthy soldiers were matched in combat experience, time passed between combat experience and the study, demographic variables (age, marital status, educ ation), and smoking status. Platelet MAO-13 was assayed fluorometrically, e go strength was measured by the Croatian version of the Ego Identity Scale, and neuroticism by the N-scale from Eysenck's EPQ-R questionnaire. Results. Soldiers with combat-related current PTSD had lower platelet MAO-B activity than the control group (9.1+/-3.9 vs. 11.9+/-4.0; p<0.05), as wel l as lower ego-strength (86.3+/-8.3 vs. 108.6+/-13.4: p<0.05) and higher ne uroticism (23.5+/-13.2 vs. 5.9+/-4.7; p<0.05). There was no association of ego strength or neuroticism with platelet MAO-B activity Conclusion. Ego identity strength and emotional stability are associated wi th successful coping with combat trauma. The involvement of platelet MAO-B activity in biological basis of ego strength and neuroticism could not be d emonstrated.