Persistent Smoking, Depression and Disease

People with smoking-related medical illnesses—such as heart disease, chronic obstructive pulmonary disease (COPD), stroke and cancer—are at much greater risk for depression. However, the warning signs are often discounted by patients and family members, who mistakenly assume depression is normal for people struggling with serious health conditions.

For example, Gerry has been smoking two-and-a-half-packs of cigarettes per day since World War II ended. He has tried to quit numerous times since his doctor first detected lung problems more than 20 years ago. Now, at age 74, Gerry suffers from heart disease and emphysema, which has resulted in an 80-percent loss of his lung capacity. As a result, Gerry labors to walk even short distances. But recently Gerry was also diagnosed with depression. Although one might assume that Gerry is depressed because he has a debilitating and life-threatening illness, recent evidence suggests that undiagnosed depression may be a hidden risk factor in the development of smoking-related illnesses such as lung cancer, heart disease and COPD. Here’s why.

Well-established link between depression and smoking

It has been well documented that smokers are at greater risk for depression than nonsmokers. Large epidemiological, or population, studies have demonstrated that the lifetime prevalence of depression among smokers is more than double that of nonsmokers. Although the statistical correlation between smoking and depression is clear, the reasons why the correlation exists are not. Is smoking a major risk factor for depression, or does depression lead to persistent smoking?

Association between depression and smoking-related illness

A 2003 University of Florida study found that more than 60 percent of patients with COPD were depressed. Patients who were currently smoking were three to four times more likely to be depressed than former smokers. All of the study participants were current or former smokers. Ninety-five percent of COPD is due to persistent and heavy smoking.

Further analysis revealed that undiagnosed depression is a major contributing factor in persistent smoking. In other words, depressed individuals are more likely to smoke heavily and have extreme difficulty quitting. There are two reasons for this:

1. Cigarette smoking produces an antidepressant effect that can, and does, mask depression. While nicotine is the primary psychoactive ingredient in tobacco smoke, numerous other chemicals also appear to have psychoactive and antidepressant properties. Smoking temporarily relieves some of the effects of depression, although details of the exact neurochemistry are still unknown.

2. Depressed smokers are more likely to have repeated failed attempts at smoking cessation because their withdrawal symptoms, such as depression and agitation, are very severe. In other words, when a depressed smoker tries to quit smoking he experiences pronounced mood swings and feelings of depression, which are relieved, almost immediately, by smoking. As a result, depressed smokers use tobacco more heavily and more persistently than nondepressed smokers, and are more likely to develop smoking-related disease.

Additional studies also have found a similar association between depression and the subsequent development of heart disease. Individuals suffering from depression are 1.5 to 3.36 times more likely to develop heart disease than nondepressed peers, partly by increasing the frequency of unhealthy behaviors, including smoking.

Treatment

Depression is a common and serious medical illness that can be effectively treated when properly diagnosed. As more doctors and health professionals become aware of the relationship between cigarette smoking, depression and disease, a more aggressive approach to treatment can be used to address depression. Gerry’s physician prescribed antidepressant medication and support therapy and although he is still very ill, his quality of life has improved dramatically.

If you have experienced feelings of depression, or currently smoke, it would be wise to talk to your employee assistance program (EAP) or your doctor. Professionals can help you get expert help, assessment and treatment.

Sources: ”Depressive symptoms in patients with COPD: Prevalence, determinants, and impact” by

David B. Coultas, MD, Drew W. Edwards, EdD, Bethany Barnett, MSPH, Gaumita Singh, BA and Peter Wludyka, PhD: The University of Florida Health Science Center, Jacksonville, Fla. Submitted to the Annals of Internal Medicine, June 2004; Devins G.M., Dion R., Pelletier L.G., Shapiro C.M., Abbey S., Raiz L.R., et al. “Structure of lifestyle disruptions in chronic disease: A confirmatory factor analysis of the Illness Intrusiveness Ratings Scale.” (2001) Med Care, 39:1097-104.

© 2004 Achieve Solutions