Longitudinal smoking patterns in survivors of childhood cancer: An update from the Childhood Cancer Survivor Study

Abstract

BACKGROUND Survivors of pediatric cancer have elevated risks of mortality and morbidity. Many late adverse effects associated with cancer treatment (eg, second cancers and cardiac and pulmonary disease) are also associated with cigarette smoking, and this suggests that survivors who smoke may be at high risk for these conditions. METHODS This study examined the self-reported smoking status for 9397 adult survivors of childhood cancer across 3 questionnaires (median time interval, 13 years). The smoking prevalence among survivors was compared with the smoking prevalence among siblings and the prevalence expected on the basis of age-, sex-, race-, and calendar time-specific rates in the US population. Multivariable regression models examined characteristics associated with longitudinal smoking patterns across all 3 questionnaires. RESULTS At the baseline, 19% of survivors were current smokers, whereas 24% of siblings were current smokers, and 29% were expected to be current smokers on the basis of US rates. Current smoking among survivors dropped to 16% and 14% on follow-up questionnaires, with similar decreases in the sibling prevalence and the expected prevalence. Characteristics associated with consistent never-smoking included a higher household income (relative risk [RR], 1.16; 95% confidence interval [CI], 1.08-1.25), higher education (RR, 1.32; 95% CI, 1.22-1.43), and receipt of cranial radiation therapy (RR, 1.08; 95% CI, 1.03-1.14). Psychological distress (RR, 0.86; 95% CI, 0.80-0.92) and heavy alcohol drinking (RR, 0.64; 95% CI, 0.58-0.71) were inversely associated. Among ever-smokers, a higher income (RR, 1.17; 95% CI, 1.04-1.32) and education (RR, 1.23; 95% CI, 1.10-1.38) were associated with quitting, whereas cranial radiation (RR, 0.86; 95% CI, 0.76-0.97) and psychological distress (RR, 0.80; 95% CI, 0.72-0.90) were associated with not having quit. The development of adverse health conditions was not associated with smoking patterns. CONCLUSIONS Despite modest declines in smoking prevalence, the substantial number of consistent current smokers reinforces the need for continued development of effective smoking interventions for survivors. Cancer 2015;121:4035-4043.