BIOL PSYCHIATRY 1990;27:245-247 245 Twenty-Four Hour Urinary Cortisol and Catecholamine Excretion in Combat-Related Posttraumatic Stress Disorder Roger Ko Pitman and Scott P. Orr Introduction Heightened adrenal cortical activity is a classic component c,f the stress response. Elevation of 24-hr excretion of urinary-free cortiso] (UFC) has been documented in depressive disorder (Stokes et al. 1984). Several of the DSM-III-R symptoms of posttraumatic stress disorder (FrSD) overlap with depression, and PTSD's comor- bidity with depressive disorder has been re- po~ed (Sierles et al. 1983). These considera- tions lead to the prediction that urinary cortisol excretion should be elevated in PTSD. Elevated cortisol excretion in conjunction with PTSD symptomatology has been reported in chroni- cally stressed civilians living in proximity to a damaged nuclear reactor (Davidson and Baum 1986), and in hostages returning from prolonged captivity (Rahe 1988). However, the only pub- lished study of UFC excretion in combat-related PTSD (Mason et al. 1986) found it to be un- expectedly decreased in nine Vietnam veteran PTSD inpatients compared with inpatients with other mental disorders. This study included no combat, or nonpsychiatric control group. Ele- From the Research Service (151), Veterans Administration Medical Center, Manchester, NH, and the Department of Psychiatry, Har- vard Medical School, Boston, MA. • Address reprint requests to Dr. Pitman, Research Service (151), VA Medical Center, 718 Smyth Road, Manchester, NH 03104. Supported by a Merit Review and Research Career Development Award (R.K.P) from the Veterans Administration. This work was performed by employees of the United States Gov- ernment during the course of official duties and is therefore in the public domain. Received February 23, 1989; revised April 20, 1989. vated 24-hr norepinepk'ine (NE) and epineph- rine (E) excretions were reported in the same PTSD subjects (Kosten et al. 1987), leading the investigators to propose that adrenal cortical and adrenal medullary activity are dissociated in PTSD, and that a high catecholamine/cortisol excretion ratio characterizes the disorder (Ma- son et al. 1988). Frankenhaueser (1980) has demonstrated the utility of ambulatory mea- surements of 24-hr urinary hormones in the study of human stress. We measured 24-hr UFC and catecholamine excretion in ambulatory Vietnam veteran wrI'SD patients and mentally healthy combat controls. Method Subjects were white male combat Vietnam vet- erans recruited for a psychophysiological study of PTSD described elsewhere (Pitman et al. 1987). Twenty met DSM-III-R (American Psy- chiatric Association, 1987) criteria for PTSD and 15 for no mental disorder (healthy). The groups were matched for age: PTSD M - 40.9 (s.d. = 6.1), healthy M = 39.5 (s.d. = 3.6) t(33) = 0.8, p -- 0.45.; and severity of combat exposure on a 14-point scale: PTSD M = 12.1 (s.d. = 2.1), healthy M = 11.1 (s.d. = 2.0), t(32) = 1.3, p = 0.21. Subjects reporting the use of potentially confounding medications, in- cluding psychotropics, were excluded. A baseline 24-hr urine collection was com- pleted at the subject's convenience before the research diagnostic interview. Following the di- This article is in the Public Domain. 0006-3223/90/$00.00