Differences by Depression Severity Category in Cigarette Smoking Among Low-Income Housing Residents

Purpose: Smoking is especially prevalent in low-income groups with additional characteristics. Smoking prevalence is estimated to be 70% among homeless individuals and 77% among low-income substance users in treatment. Among the low-income and mentally ill, the smoking prevalence is 31.7%. The most common mental illness, depression, has been frequently studied as a comorbidity of smoking. Approximately 60% of individuals with depression are current or former smokers. This association has often been studied with a binary measure of depression, which may overlook the effects of depression severity on smoking behavior. Methods: This study used data collected from participants in subsidized housing enrolled in a health coaching intervention called “Mobile Community Health Assistance for Tenants” or “m.chat.” The sample included 420 residents with a mental health condition. A zero-inflated Poisson regression was used to determine the association between smoking cigarettes and four levels of depression: minimal or none (PHQ9 ≤4), mild (PHQ9 5 - 9), moderate (PHQ9 10 - 14), and severe (PHQ9 ≥15). Results: The majority (73.3%) of individuals smoked an average of 7.5 cigarettes per day. In our population with a high prevalence of smoking and depression, when we controlled for depression severity, we found that those without depressive symptoms were more likely to smoke. Depression risk was significantly associated with both the likelihood of smoking (chi-sq=11.03, p=0.0116) and the number of cigarettes smoked among smokers (chi-sq=14.89, p=0.0019). Moderate depression severity resulted in increased odds of being a smoker (OR=2.16, 95%CI:[1.01,4.64]), but a decrease in the number of cigarettes smoked (RR=0.87, 95%CI:[0.77,0.99]). Conclusion: Further study is warranted to examine the relationship between depression severity and cigarette smoking.