Association of serum cotinine levels and lung cancer mortality in non-smokers

This study was performed to quantify the association between mortality and known and unknown secondhand smoke (SHS) exposure as measured by cotinine levels in non-smokers. Data collected from 1999 to 2010 in the National Health and Nutrition Examination Survey (NHANES) were linked to the National Death Index. Self-reported non-smokers aged ≥20 years (N = 20 175) were studied. Serum cotinine was measured at recruitment; non-smokers were those with cotinine below the reported race-specific cut-off points (5.92, 4.85 and 0.84ng/ml for non-Hispanic blacks, non-Hispanic whites and Mexican Americans, and 3.08ng/ml for all other groups). Serum cotinine levels were significantly associated with overall survival (HRadj 1.17, 95% CI: 1.13–1.22 per natural-log unit change in cotinine), death for all medical causes, lung cancer, all cancers and heart diseases, after adjustment for gender, race/ethnicity, body mass index, smoking history and education. Similar results were observed when non-smokers reporting no SHS exposure at home or work were analyzed. There was a statistically significant trend in years of life lost (YLL), adjusted for confounders, across cotinine categories both in non-smokers (YLLadj: 5.6, 6.4, 6.8, 7.5; P for trend < 0.0001) and non-smokers reporting no SHS exposure (YLL adj: 5.5, 6.1, 6.3, 6.7; P for trend = 0.002). Serum cotinine levels identify SHS-attributable mortality in subjects who would have otherwise been overlooked by questionnaire data, provi...
Source: Carcinogenesis - Category: Cancer & Oncology Authors: Tags: Original Manuscript Source Type: research