Does Asthma Increase Adult Suicide Risk?

May 14, 2008 -- New research suggests a link between asthma and an increased risk for suicide attempts in adults, but not suicidal thoughts without attempts.

Compared to the general population, people in the study with asthma were roughly 50% more likely to attempt suicide after researchers controlled for established suicide risk factors, including depression and alcohol abuse.

Smoking cigarettes, which is a risk factor for asthma, was also found to be independently associated with an increased risk for suicide attempts. But this did not fully explain the link between asthma and attempted suicide.

The study is the first to examine the association between asthma and suicidal thinking -- with and without suicide attempts -- using a nationally representative sample of adults.

It did not address the issue of whether asthma treatment increases suicide risk -- a topic that has been in the news since early this spring, when the FDA announced an investigation of a possible link between a widely prescribed allergy and asthma drug and suicide.

While many questions remain unanswered, researcher Diana E. Clarke, PhD, says doctors should be made aware of a possible link between asthma and suicide.

"Smoking and mental health illnesses like depression, panic disorder, and alcohol abuse were all associated with an increased risk for suicide [in the study], but when we controlled for these things the link with asthma was still there," she tells WebMD.

Asthma and Suicide

Clarke and colleagues examined data on 5,692 adults aged 18 and older participating in a nationwide health study between early 2001 and the spring of 2003.

Approximately 12% of the participants reported a history of asthma, 8.7% had experienced suicidal thoughts at some point in their lives, and 4.2% had attempted suicide.

Female sex, being a smoker, experiencing depression or anxiety, and alcohol abuse were all associated with an increased risk for suicide attempts in asthma patients, but none of these associations fully explained the asthma link.

More research is needed to confirm the association, but Clarke says asthma patients who express suicidal thoughts should be referred to mental health specialists.

The study appears in the May issue of the Annals of Allergy, Asthma and Immunology.

Allergy and asthma specialist Richard A. Nicklas, MD, of the George Washington Medical Center, describes the research linking asthma to suicide as preliminary and far from conclusive.

But he adds that his own patients seem to experience more depression during times when pollen counts are highest.

"That is anecdotal," he tells WebMD. "But what has been shown in studies is that there is a decrease in cognitive function -- with more fatigue, irritability and difficulty concentrating -- among patients experiencing [allergy and asthma] symptoms. Whether this is associated with something as serious as suicide, though, is another question."