Tags

Type your tag names separated by a space and hit enter

Is the inverse association between selenium and bladder cancer due to confounding by smoking?
Am J Epidemiol 2015; 181(7):488-95AJ

Abstract

Selenium has been linked to a reduced risk of bladder cancer in some studies. Smoking, a well-established risk factor for bladder cancer, has been associated with lower selenium levels in the body. We investigated the selenium-bladder cancer association in subjects from Maine, New Hampshire, and Vermont in the New England Bladder Cancer Case-Control Study. At interview (2001-2005), participants provided information on a variety of factors, including a comprehensive smoking history, and submitted toenail samples, from which we measured selenium levels. We estimated odds ratios and 95% confidence intervals among 1,058 cases and 1,271 controls using logistic regression. After controlling for smoking, we saw no evidence of an association between selenium levels and bladder cancer (for fourth quartile vs. first quartile, odds ratio (OR) = 0.98, 95% confidence interval (CI): 0.77, 1.25). When results were restricted to regular smokers, there appeared to be an inverse association (OR = 0.76, 95% CI: 0.58, 0.99); however, when pack-years of smoking were considered, this association was attenuated (OR = 0.91, 95% CI: 0.68, 1.20), indicating potential confounding by smoking. Despite some reports of an inverse association between selenium and bladder cancer overall, our results, combined with an in-depth evaluation of other studies, suggested that confounding from smoking intensity or duration could explain this association. Our study highlights the need to carefully evaluate the confounding association of smoking in the selenium-bladder cancer association.

Authors

No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, N.I.H., Extramural
Research Support, N.I.H., Intramural
Research Support, U.S. Gov't, Non-P.H.S.

Language

eng

PubMed ID

25776013

Citation

Beane Freeman, Laura E., et al. "Is the Inverse Association Between Selenium and Bladder Cancer Due to Confounding By Smoking?" American Journal of Epidemiology, vol. 181, no. 7, 2015, pp. 488-95.
Beane Freeman LE, Karagas MR, Baris D, et al. Is the inverse association between selenium and bladder cancer due to confounding by smoking? Am J Epidemiol. 2015;181(7):488-95.
Beane Freeman, L. E., Karagas, M. R., Baris, D., Schwenn, M., Johnson, A. T., Colt, J. S., ... Silverman, D. T. (2015). Is the inverse association between selenium and bladder cancer due to confounding by smoking? American Journal of Epidemiology, 181(7), pp. 488-95. doi:10.1093/aje/kwu324.
Beane Freeman LE, et al. Is the Inverse Association Between Selenium and Bladder Cancer Due to Confounding By Smoking. Am J Epidemiol. 2015 Apr 1;181(7):488-95. PubMed PMID: 25776013.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Is the inverse association between selenium and bladder cancer due to confounding by smoking? AU - Beane Freeman,Laura E, AU - Karagas,Margaret R, AU - Baris,Dalsu, AU - Schwenn,Molly, AU - Johnson,Alison T, AU - Colt,Joanne S, AU - Jackson,Brian, AU - Hosain,G M Monawar, AU - Cantor,Kenneth P, AU - Silverman,Debra T, Y1 - 2015/03/15/ PY - 2015/3/18/entrez PY - 2015/3/18/pubmed PY - 2015/5/23/medline KW - bladder cancer KW - case-control study KW - selenium KW - smoking SP - 488 EP - 95 JF - American journal of epidemiology JO - Am. J. Epidemiol. VL - 181 IS - 7 N2 - Selenium has been linked to a reduced risk of bladder cancer in some studies. Smoking, a well-established risk factor for bladder cancer, has been associated with lower selenium levels in the body. We investigated the selenium-bladder cancer association in subjects from Maine, New Hampshire, and Vermont in the New England Bladder Cancer Case-Control Study. At interview (2001-2005), participants provided information on a variety of factors, including a comprehensive smoking history, and submitted toenail samples, from which we measured selenium levels. We estimated odds ratios and 95% confidence intervals among 1,058 cases and 1,271 controls using logistic regression. After controlling for smoking, we saw no evidence of an association between selenium levels and bladder cancer (for fourth quartile vs. first quartile, odds ratio (OR) = 0.98, 95% confidence interval (CI): 0.77, 1.25). When results were restricted to regular smokers, there appeared to be an inverse association (OR = 0.76, 95% CI: 0.58, 0.99); however, when pack-years of smoking were considered, this association was attenuated (OR = 0.91, 95% CI: 0.68, 1.20), indicating potential confounding by smoking. Despite some reports of an inverse association between selenium and bladder cancer overall, our results, combined with an in-depth evaluation of other studies, suggested that confounding from smoking intensity or duration could explain this association. Our study highlights the need to carefully evaluate the confounding association of smoking in the selenium-bladder cancer association. SN - 1476-6256 UR - https://www.unboundmedicine.com/medline/citation/25776013/Is_the_inverse_association_between_selenium_and_bladder_cancer_due_to_confounding_by_smoking L2 - https://academic.oup.com/aje/article-lookup/doi/10.1093/aje/kwu324 DB - PRIME DP - Unbound Medicine ER -