Substance Use, Depression, and Illness Perception Among Cancer Patients

Objectives: Research demonstrates a link between alcohol and tobacco use in the development of cancer, but limited research exists regarding substance use after a cancer diagnosis. In this study, we examine the rates of alcohol and tobacco use in advanced cancer patients, investigate the link between depression and tobacco and alcohol use pre- and post-diagnosis, and determine the relationship between illness perception and tobacco and alcohol use post-diagnosis. Methods: We performed a secondary data analysis on 2 prospective studies of patients with advanced gastrointestinal cancers. We administered a battery of questionnaires to assess substance use, depression, and illness perception. Results: Patients who reported tobacco use post-diagnosis had higher levels of depressive symptoms when compared to patients with a history of tobacco use or no alcohol or tobacco use (Kruskal-Wallis = 25.77, p < .0125). Patients who reported being more emotionally affected by their illness reported greater tobacco use (MannWhitney U = 17, 284.5, p < .003). Conclusions: Tobacco use post-diagnosis was associated with higher levels of depression.