Results: The mean total number of comorbidities was higher among those with PTSD (17.7; SD, 6.1) than in trauma-exposed controls (14.1; SD, 5.2; P < 0.001). For 24 of 171 assessed clinical outcomes, morbidity was greater in the PTSD group, including for conditions of the gastrointestinal, hepatic, cardiovascular, and respiratory systems, sleep disorders, and laboratory pathology measures. In regression analyses including demographic factors, PTSD remained positively associated with 17 adverse outcomes; after adjusting for the severity of depressive symptoms, it remained significantly associated with ten. Conclusion: PTSD in Australian Vietnam veterans is associated with comorbidities in several organ systems, independent of trauma exposure. A comprehensive approach to the health care of veterans with PTSD is needed.