Smoking Cessation Health Center

Smokers May Think More About Suicide

March 7, 2005 - Smokers think more about suicidesuicide than nonsmokers, a 10-year study shows.

Those who surround themselves with clouds of cigarette smoke are 82% more likely than nonsmokers to think of ending their own lives.

The good news: quitting smokingquitting smoking apparently lifts not only the cloud of smoke, but also the cloud of suicidal gloom. Past smokers are no more likely than nonsmokers to be haunted by thoughts of suicide.

The findings come from Michigan State University researcher Naomi Breslau, PhD, and colleagues. They appear in the March issue of Archives of General Psychiatry.

"Compared with never daily smokers, current daily smokers had an increased risk of subsequent suicidal thoughts or attempt," Breslau and colleagues write. "In contrast, past daily smokers were not at increased risk for subsequent occurrences of suicidal thought or attempt."

The researchers accounted for major depression and drug/alcohol abuse. That means that smokers' increased thoughts of suicideincreased thoughts of suicide weren't simply the result of depression or substance abuse, each of which greatly increases a person's risk of suicide. However, this also means the study likely underestimated the link between smoking and suicide.

A 10-Year Study

Breslau's team interviewed about 1,000 21- to 30-year-olds enrolled in a Michigan health maintenance organization. The researchers first contacted them in 1989 and interviewed them again three, five, and 10 years later.

Obviously, this kind of study didn't identify people who actually killed themselves. But suicidal thinking is more than just reflecting on Hamlet's famous soliloquy. It can reflect serious psychological problems.

In the 1999-2001 assessment period, for example, 8% of study participants reported suicidal thoughts or suicide attempts. Among current daily smokers, 16% reported thinking about or attempting suicide.

Could smoking cause suicide? It's possible. Smoking does alter a person's brain chemistry in ways that could be linked to depression. Indeed, the current findings suggest that prior major depression partly accounted for smokers' increased risk of suicidal thoughts.

But Breslau and colleagues note that they haven't found a smoking gun.

"The question as to whether smoking per se is an independent cause of suicidal behavior cannot be definitively answered here," they write.