Lung ills linked to suicidal thoughts.

Lung disorders such as asthma don't just interfere with breathing. Sufferers of these ailments report thoughts of suicide and self-harm far more often than do people treated for other physical illnesses, a new study finds.

Previous studies have uncovered high rates of suicidal thinking and suicide attempts in individuals diagnosed with major depression. Thoughts of killing or hurting oneself are even more common in patients diagnosed with a pulmonary disease than in those with major depression, reports a team led by Renee D. Goodwin of Columbia University.

"It may be worthwhile for physicians to inquire directly about mental-health problems among individuals who present with [pulmonary] illnesses," Goodwin says. Even in patients without depression, pulmonary disease should be considered a red flag, she and her colleagues conclude in the July/August Psychosomatic Medicine.

Goodwin's group studied 3,000 patients treated at any of eight primary care clinics across the United States. Participants, ranging in age from 29 to 63, completed a survey inquiring about psychological symptoms that characterize common mental disorders. The survey question about suicidal thinking asked, "Have you had thoughts that you would be better off dead or of hurting yourself in some way for at least several days in the last two weeks?"

Overall, 9 percent of the patients responded affirmatively to that query.

After statistically controlling for differences in age, education, and marital status and for the presence of mental disorders, the researchers observed an association between pulmonary disease and suicidal thinking. Recent thoughts of killing or hurting oneself occurred in 6.3 percent of those who had neither pulmonary disease nor major depression, 9.5 percent of those with major depression but not pulmonary disease, 11 percent of those with pulmonary disease but not major depression, and 12 percent of those with both pulmonary disease and depression.

Reports of suicidal thoughts were not elevated among patients with hypertension, heart conditions, arthritis, diabetes, cancer, liver disease, or kidney disease.

The scientists note several possible explanations for the link between pulmonary disease and suicidal thinking. First, the suffering and physical limitations associated with conditions such as asthma and chronic obstructive pulmonary disease may create a sense of hopelessness and despair. Or medications used to treat pulmonary ailments--such as the steroid-based drugs prescribed for asthma--may amplify feelings of sadness and anxiety.

Alternatively, cigarette smoking and excessive alcohol use may contribute to both pulmonary disease and depression.

Pulmonary diseases often induce panic attacks, which could contribute to thoughts of killing oneself, comment internist Bruce L. Rollman and psychiatrist M. Katherine Shear, both of the University of Pittsburgh School of Medicine, in an editorial published with Goodwin's report. Rollman and Shear say that whatever accounts for the new finding, "an association of [suicidal thinking] with pulmonary disease appears to be valid."

Goodwin's results need to be confirmed in larger populations of patients, they add. Although two earlier studies reported an increased rate of suicidal thoughts among people with malignant cancers, the new investigation may have included too few cancer patients to detect this link, Rollman and Shear say.