NEW YORK (Reuters Health) - Emotionally stressful experiences, like the death of a loved one or the end of a relationship, may make asthma more difficult to deal with, research suggests.

In a study of 189 adults with asthma, researchers found that those who'd gone through more negative events in the last year tended to have poorer asthma-related quality of life -- including more asthma symptoms, poorer emotional well-being and more worries over their health.

The relationship was particularly strong among asthmatics with lower incomes, according to findings published in the medical journal Thorax.

Negative life events -- from the death of a family member to divorce to the loss of a home -- are indicative of long-term stress, which can take a toll on physical health. For asthma sufferers, the stress may make them perceive their condition as worse than before, or it may actually worsen their symptoms, according to study co-author Dr. Paul Blanc.

"Negative life events could magnify a person's perception of how asthma affects one's life, but the mechanism could also be through a true worsening of health status," Blanc, a professor of medicine at the University of California San Francisco, told Reuters Health.

For their study, Blanc and his colleagues used standard questionnaires to measure major negative events in participants' lives and their asthma-related quality of life. They also measured their lung function and blood levels of cotinine, which signifies a person's exposure to tobacco smoke.

Overall, the study found, asthma-related quality of life declined as the number of recent stressful events climbed. Study participants with relatively lower incomes seemed particularly vulnerable to these life stressors.

While life's negative experiences may not be preventable, Blanc and his colleagues conclude, healthcare providers should be aware that they take can a toll on patients' health.

"Doctors need to take the whole person into account," Blanc said. Helping patients deal with stress is important in managing asthma, as well as other chronic diseases, he noted.