American Journal of Epidemiology Advance Access originally published online on June 15, 2006
American Journal of Epidemiology 2006 164(4):358-366; doi:10.1093/aje/kwj211
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Original Contribution |
Shift Work, Light at Night, and Breast Cancer on Long Island, New York
1 Department of Preventive Medicine, School of Medicine, Stony Brook University, Stony Brook, NY
2 Department of Community Health, University of Connecticut Health Center, Farmington, CT
3 Department of Epidemiology, School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC
Correspondence to Dr. Erin S. O'Leary, Department of Preventive Medicine, Stony Brook University, Stony Brook, NY 11794-8036 (e-mail: eoleary{at}notes.cc.sunysb.edu).
The hypothesized association between breast cancer and circadian disruption was evaluated in the Electromagnetic Fields and Breast Cancer on Long Island Study. Participants included 576 women with breast cancer diagnosed from August 1996 to June 1997 and 585 population-based controls (87% and 83% participation rates, respectively) aged <75 years and living in the same Long Island, New York, home for 
15 years. An in-person interview ascertained light-at-night exposure histories through shift work (previous 15 years) and at home (previous 5 years). Odds ratios and 95% confidence intervals were estimated by unconditional multivariate logistic regression. Breast cancer was not associated with overall shift work (odds ratio (OR) = 1.04, 95% confidence interval (CI): 0.79, 1.38) or evening shift work (OR = 1.08, 95% CI: 0.81, 1.44). However, overnight shift workers were at lower risk than women never working shifts (OR = 0.55, 95% CI: 0.32, 0.94). Women who frequently turned on lights at home during sleep hours (twice/week and twice/night) had increased risks (OR = 1.65, 95% CI: 1.02, 2.69). The latter results suggest positive associations with residential light-at-night exposure, or they could reflect response biases. Furthermore, overall and evening shift work were not significant factors, and analyses of overnight shift workers yielded reduced risk estimates. The study thus provides mixed evidence for the light-at-night hypothesis.
breast neoplasms; case-control studies; circadian rhythm; electromagnetic fields; light; melatonin; occupation; women
Abbreviations: CI, confidence interval; EBCLIS, Electromagnetic Fields and Breast Cancer on Long Island Study; LIBCSP, Long Island Breast Cancer Study Project; OR, odds ratio
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  R. G Stevens Light-at-night, circadian disruption and breast cancer: assessment of existing evidence Int. J. Epidemiol., August 1, 2009; 38(4): 963 - 970. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 X. Zhang and H. Zarbl Chemopreventive Doses of Methylselenocysteine Alter Circadian Rhythm in Rat Mammary Tissue Cancer Prevention Research, July 1, 2008; 1(2): 119 - 127. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. H. Wu, R. Wang, W.-P. Koh, F. Z. Stanczyk, H.-P. Lee, and M. C. Yu Sleep duration, melatonin and breast cancer among Chinese women in Singapore Carcinogenesis, June 1, 2008; 29(6): 1244 - 1248. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. Cai, J. Rambaud, M. Teboul, I. Masse, G. Benoit, J.-A. Gustafsson, F. Delaunay, V. Laudet, and I. Pongratz Expression Levels of Estrogen Receptor Are Modulated by Components of the Molecular Clock Mol. Cell. Biol., January 15, 2008; 28(2): 784 - 793. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. Patel Shift work, light at night and risk of breast cancer. Occup. Med., September 1, 2006; 56(6): 433 - 433. [Full Text] [PDF]
|
|