Secondhand Smoke Exposure Among Community-Dwelling Adult Cancer Survivors in the United States: 1999-2012.

Background: Little is known about the prevalence of second-hand smoke exposure (SHSe) among cancer survivors. We sought to determine the prevalence, trends, and correlates of SHSe among nonsmoking adult cancer survivors in the United States. Methods: Interview and serum cotinine data for nonsmoking adults, age 20 years and older, with a history of cancer (N = 686) were obtained from consecutive two-year cross-sectional cycles of the National Health and Nutrition Examination Survey from 1999 to 2012. SHSe was defined as serum cotinine 0.05-10 ng/mL among nonsmokers. We calculated and trended the prevalence of SHSe among nonsmoking cancer survivors. Multivariable logistic regression was used to examine the associations of SHSe with socio-demographic, smoking, and clinical characteristics. Survey weights were applied in estimating prevalence rates, adjusted ORs, and confidence intervals (CI). Results: The weighted aggregate SHSe and self-reported indoor SHSe prevalence rates over the study period were 28.26% (95% CI: 24.97%-31.55%) and 4.53% (95% CI: 3.48%-5.57%), respectively. SHS exposure declined from 39.61% (95% CI: 27.88%-51.34%) in 1999/2000 to 15.68% (95% CI: 9.38%-21.98%) in 2011/2012 (P-trend < 0.001). Age >= 60 years was protective against SHSe, while being black, having less than high school education, poverty, and a smoking-related cancer history were associated with higher odds of SHSe. Conclusions: Fortunately, SHSe among nonsmoking cancer survivors in the United States is on the decline, although certain subgroups remain disproportionately burdened. Impact: These findings highlight clinical and public health imperatives to target socioeconomically disadvantaged nonsmoking cancer survivors to reduce their SHSe. (C) 2017 AACR.