Studies Link Depression to Smoking
People who have experienced depression are especially vulnerable to nicotine addiction and have a particularly hard time quitting smoking, according to new research that suggests that many people use smoking as a form of “self-medication” against anxiety and pain.
The findings are considered important because of the dire health consequences of smoking and the difficulties of stopping. They suggest that, for some people, it may be unrealistic to expect to quit without first being treated for depression.
“This is probably the best evidence yet that certain people are more susceptible to drug addiction than others,” said Dr. Alexander H. Glassman of Columbia University, an author of one of two studies published today in the Journal of the American Medical Assn. “It certainly raises the question: Is this going to be true for other drugs?”
The reasons behind what Glassman called this “chronic and pernicious interrelationship” are not yet clear.
Because nicotine is a stimulant, researchers suspect that some smokers use it to fend off the anxiety and discontent that characterize depression. Over time, those feelings may come to trigger cravings for nicotine because it has alleviated them in the past.
Similarly, the anxiety that accompanies nicotine withdrawal may be more severe among depressed ex-smokers and more likely to drive them back to cigarettes. Researchers say some depression-prone people have been driven back into depression by an attempt to quit smoking.
Another possible explanation is that some factors, such as low self-esteem, may predispose people to both depression and smoking. Or, there may be a genetic factor that can lead to both depression and smoking, some researchers suggest.
“I think there are a lot of people who stop (smoking) easily and look down on the person who can’t, as though they are a weaker kind of human being,” Glassman said. “ . . . I think (this finding) says it’s something biological, not a moral issue.”
Glassman and others pointed out that, as social pressure to stop smoking mounts and those who are capable of quitting do so, the pool of persistent smokers will increasingly consist of people with a history of depression or vulnerable to depression.
Because women, among other groups, are especially prone to depression in the United States, nicotine may become an increasingly female addiction, Glassman said. He said the balance is already shifting, and women have been less successful than men in quitting smoking.
One of the two new studies, by researchers at the federal Centers for Disease Control, is based on data collected in a general health and nutrition survey of randomly selected people. The researchers explored smoking habits and self-reported symptoms of depression.
They found that people whose symptoms amounted to a clinical diagnosis of depression were significantly more likely than others to be current smokers. Similarly, they were significantly less likely to have successfully quit.
The other study is based on a mental health survey of randomly selected people. The researchers found that people who had experienced major depressive disorder, or severe depression, were twice as likely as others to be, or to have been, regular smokers.
Researchers said it would be premature to prescribe anti-depressants for people who have difficulty quitting smoking. But Glassman said he is currently studying the possibility and “it really looks like it’s going to work.”
