Differential diagnosis of PTSD
Patients with PTSD are more likely to have substantial psychiatric comorbidity than are those without the disorder.3 Possible reasons include suspected self-medication of PTSD symptoms, particularly among patients with substance abuse, and the possible overreporting of symptoms by patients. Psychiatrists should maintain a high level of suspicion for PTSD when managing a new or existing patient with psychopathology.
Citing data from the National Comorbidity Study of the Institute for Social Research at the University of Michigan, Kessler and others in 1995 noted that more than 80 percent of individuals with PTSD meet criteria for at least one other psychiatric diagnosis. Roughly half of PTSD sufferers met criteria for three or more comorbidities.3
Kathleen Brady, MD, professor of psychiatry at the Medical University of South Carolina in Charleston, noted in a 1997 study that affective disorders, other anxiety disorders, somatization, substance abuse, and dissociative disorders are common comorbidities of PTSD.5 Dr. Shalev and colleagues in one study found that a history of major depressive disorder may increase the severity of posttraumatic morbidity.6 Dr. Brady and others also have found that PTSD patients with a comorbid substance abuse disorder experience severe PTSD symptoms while in a withdrawal state.7
PTSD and comorbidities: Overlapping symptoms
| Disorder | Symptoms that overlap with PTSD |
|---|---|
| Adjustment disorder | Extreme response to stressor. Stressor is not necessarily extreme in nature (e.g., spouse leaving, being fired), and the response might not meet criteria for PTSD.4 |
| Depression | Diminished interest, restricted range of affect, sleep difficulties, or poor concentration.5 |
| Dissociative disorders | Inability to recall important information about past trauma, sense of detachment from oneself, derealization, nightmares, flashbacks, startle responses, or lack of affective response (e.g., onset of dissociative fugue may be tied to past trauma).4 |
| Generalized anxiety | Irritability, hypervigilance, or increased startle reflex.5 |
| Obsessive-compulsive disorder | Recurrent intrusive thoughts (not related to trauma in obsessive-compulsive disorder).4 |
| Panic attacks | Heart palpitations or increased heart rate, sense of detachment, nausea or abdominal distress.4 |
| Psychosis | Illusions, hallucinations, or other perceptual disturbances (may be confused with flashbacks in PTSD).4 |
| Substance abuse disorder | Hallucinations, illusions, diminished interest in or avoidance of significant activities, or social estrangement.4 |
PTSD often is overlooked in the presence of other psychiatric diagnoses. Meuser et al in 1998 studied 275 patients with schizophrenia and bipolar disorder. As many as 98 percent of patients reported lifetime exposure to at least one traumatic event. The researchers found diagnosable PTSD in 119 (43 %) of the subjects, but only three (2%) had the diagnosis in their charts.8
In a later study, Dr. Brady and others cited substantial symptom overlap between PTSD and other psychiatric diagnoses, particularly major depressive disorder. This can contribute to underdiagnosis of PTSD, the researchers found.7 (Box 2).
WATCH FOR SIGNS OF PTSD IN CHILDREN
Children also have been experiencing stress disorders since Sept. 11, says Arshad Husain, MD, professor and chief of child and adolescent psychiatry and director of the International Center for Psychosocial Trauma at the University of Missouri-Columbia. Such disorders manifest as sleep disturbances, anxiety, hyperarousal/hyperactivity, and nightmares.
Young children regress and cling to their parents, and are frightened of the dark or noises, Dr, Husain notes. Those who are toilet-trained can suddenly wet the bed, become neurotic, and demand attention. School-age children are more fearful; they may not want to go to school, their schoolwork may decline, and they may have trouble paying attention. Dr. Husain suggests discussing the trauma and devising a plan of action with them in case the trauma recurs.
The media’s role in reporting on the aftermath of the attacks—and triggering traumatic reactions as an unintended consequence—cannot be overlooked. Two recent studies performed after the Oklahoma City bombing suggest that television reports of that atrocity precipitated PTSD symptoms in middle-school children 7 weeks after the bombing,23 and in geographically distant sixth-graders 2 years after the attack.12 It was not clear whether any of these students had prior PTSD or other psychopathology.
Psychiatric education in the schools is especially crucial in light of the school violence that has occurred in America in recent years. Dr. Husain believes that the children who commit violence are victims of abuse. If teachers early on can identify children who show evidence of stress disorders, they can refer them to trained psychiatrists, catching those who need help before tragedies occur. “It is the psychiatric equivalent of CPR,” Dr. Husain says.
Dr. Brady recommends that psychiatrists and primary care physicians routinely screen patients for exposure to traumatic events. Ask patients specifically about their reaction to such events and encourage them to talk about it. Patients often feel either guilty or embarrassed about the traumatic event, or do not believe it affects their presenting complaints, she notes. Other approaches may be needed to identify the risk of PTSD in children (Box 3).