Predeployment and in-theater diagnoses of American military personnel serving in Iraq

This purpose of this study was to determine the incidence and types of preexisting mental disorders among military personnel who received mental health services in an Iraqi war zone.

The study examined psychiatric histories of 1,078 American military personnel (Marines, 65%; Army, 23%; Navy, 11%; and Air Force, <1%) deployed to Iraq and seen by in-theater mental health providers between January 2006 and February 2007.

Among the 1,078 patients, the most frequent in-theater diagnoses were anxiety (24%), adjustment (23%), and mood (19%) disorders. Twenty-nine percent of the sample (N=308) had a psychiatric diagnosis in their medical records before their first encounter with mental health services in Iraq (Navy patients, 42%; Army patients, 39%; and Marine Corps patients, 23%). The mean time between last predeployment diagnosis and first in-theater mental health encounter was 21 months. For patients with a prior diagnosis, the highest rate of relapse (receipt of the same diagnosis in theater) was for attention-deficit hyperactivity disorder (57%), followed by anxiety disorders (44%)--especially posttraumatic stress disorder (PTSD) (55%)--mood disorders (38%), and adjustment disorders (32%).

A significant proportion of military personnel who experienced mental health problems in a combat zone had preexisting psychiatric conditions. Because more than half of predeployment diagnoses were received in the nine months before the in-theater mental health encounter, further study may be advisable to determine whether a time-based algorithm for deployability is needed, particularly for PTSD, for which a high rate of repeat diagnosis in theater was found.