Patients who are most at risk appear to be those who suffered from mood disorders, such as depression or anxiety, before they were diagnosed with cancer. The study found that 75 percent of breast cancer patients with PTSD had previous mood disorders.
"PTSD does occur in breast cancer patients, but not at greater rates than other psychiatric problems such as depression," said Deanna Golden-Kreutz, co-author of the study and a research associate in psychology at Ohio State University.
The findings suggest doctors shouldn't focus on PTSD when evaluating cancer patients for psychological problems, said study co-author Barbara Andersen, a professor of psychology at Ohio State.
"It's important to screen cancer patients for all kinds of depressive and anxiety symptoms and disorders, particularly asking about the past history of mood disorders," Andersen said.
The researchers presented their findings August 23 in Chicago at the annual meeting of the American Psychological Association.
PTSD is a psychiatric disorder that can occur following the experience or witnessing of life-threatening events, including cancer. Those with PTSD may have recurrent images, flashbacks and dreams about their diagnosis or treatment. They may try to avoid thoughts, feelings, activities or people, and may suffer from sleep disturbances, irritability, difficulty concentrating and other symptoms.
Other studies have tried to determine whether PTSD occurs in cancer patients, but have had widely differing results, finding that anywhere from 0 to 52 percent of cancer patients experience PTSD. Part of the problem is that these studies used differing research methods, often had small samples, examined cancer patients at varying times during diagnosis and treatment, and had other issues that make it hard to generalize from them, Andersen said.
In their study, the Ohio State researchers were able to evaluate a sample of women breast cancer patients who were participating in a long-term study of stress and immunity at the university.
They screened women for PTSD symptoms 18 months after they were diagnosed, which was about six months after their treatment had ended. They then followed-up with select patients in another 18 months. As a result of the initial screening they separated women into those who had low, moderate and high symptoms of PTSD. In order to best compare women who may be at risk for PTSD, the researchers then did further study of the 33 women with high level of symptoms and 39 women with low levels of symptoms. These two groups were similar in terms of demographics, stage of disease and treatment.
The researchers did a diagnostic assessment that examined the women's history of psychiatric disorders, traumatic events in their lives, and family psychiatric history. They also tested them for mood and anxiety disorders, alcohol and drug use, and overall functioning.
Results showed that about 30 percent of the women with a high level of symptoms did have PTSD, compared with just over 15 percent of those with low-level symptoms.
There was no difference between the high and low symptom groups in terms of family psychiatric history. However, those with a high level of symptoms were significantly more likely than others to have had past psychiatric treatment (nearly 80 percent of the high-symptom women had previous treatment), had significantly more traumatic events in their lives, and were much more likely to have had mood disorders.
The results suggest that doctors should be concerned about the mental health of people with cancer, Andersen said. But there doesn't need to be a particular focus on PTSD.
"For the vast majority of patients with breast cancer, the diagnosis and treatment of their disease won't trigger PTSD," Andersen said. "Only a small subset of patients seem to be at risk, and they can be best identified by screening for mood disorders. Our results suggest screening for mood disorders will capture three-quarters of the women most at risk for PTSD."
The study was also co-authored by Rebecca Shelby, a graduate student at Ohio State. The research was funded by the American Cancer Society, the U.S. Army, the National Institute of Mental Health and the National Cancer Institute.
Contact: Deanna Golden Kreutz, (614) 292-5170; Golden-kreutz.1@osu.edu
Barbara Andersen, (614) 292-4236; Andersen.1@osu.edu
Written by Jeff Grabmeier, (614) 292-8457; Grabmeier.1@osu.edu