Depression is a significant predictor of worse quality of life and perceived shortness of breath in patients awaiting lung transplantation, according to a presentation at the annual meeting of the American Thoracic Society. The negative effects of depression are above and beyond other factors, such as lung function and the underlying disease, the presenter said.

Additionally, investigators believe that efforts to treat depression could possibly improve the outcomes after lung transplantation. Although their study focused on patients awaiting transplantation, the researchers say that what they are learning about depression could also help other patients with severe lung disease, such as the estimated 16 million Americans who suffer from chronic obstructive pulmonary disease.

"These findings represent an example of how psychological factors can impact physical health," said Scott Palmer, M.D., study presenter. "The effect of depression is quite striking in predicting a lung patient's quality of life as well as their perceived shortness of breath.

"The findings also suggest that while we have many medical treatments for these patients, if we don't address the issue of anxiety and depression we might have less impact on their quality of life, and possibly their ultimate outcomes," Palmer added.

The report is the first analysis of data being collected on patients awaiting lung transplants enrolled in a five-year trial funded by the National Heart, Lung and Blood Institute of the National Institutes of Health (USA). The trial's goal is to determine whether a telephone-based program of stress and anxiety reduction conducted prior to transplant has any effect on outcomes after surgery.

"Patients waiting for a transplant are under so much stress and anxiety," said collaborator James Blumenthal, Ph.D. "They worry about when the call will come or whether they'll survive the operation. In most cases, patients must relocate to the transplant center to wait for an available organ, which takes them away from their usual emotional support systems."

In the current research, the first 99 patients enrolled in the trial took a battery of tests to measure depression and anxiety; they also completed questionnaires covering quality of life issues and perceived shortness of breath.

The median number of days that patients had been on the waiting list was 77 days. Nationally, patients awaiting lung transplant wait an average of 18 months from the time they are listed until they undergo the operation.

The researchers then performed statistical analyses to determine which of the following variables seemed to best predict quality of life and shortness of breath issues: social support, depression, gender, age, time on waiting list, underlying disease, or lung function.

"Our analysis suggests that while lung function and underlying disease are important predictors of pulmonary quality of life and shortness of breath, depression appears to be a stronger predictor," Palmer said. "We need more studies to evaluate different interventions to see if they have any impact on quality of life and post-transplant outcomes."

The current trial, whose results should be available in two years, will be the first to gauge whether psychological interventions can improve the outcomes of lung transplant patients. Other possible interventions include medications or exercise. The researchers add that there is an integral link between psychological status and lung function.

"Often, when a lung patient is short of breath, he or she becomes anxious or agitated, which can then cause them to breathe faster and shallower - it can then quickly become a vicious cycle," Blumenthal said. "Anything we can do to lessen the degree of anxiety for lung patients should be of benefit to their perceived quality of life."