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. 2020 Jan 20;17(2):659.
doi: 10.3390/ijerph17020659.

Night Shift Work-A Risk Factor for Breast Cancer

Marta Szkiela  1 , Ewa Kusideł  2 , Teresa Makowiec-Dąbrowska  3 , Dorota Kaleta  1
Affiliations

Night Shift Work-A Risk Factor for Breast Cancer

Marta Szkiela et al. Int J Environ Res Public Health. .

Abstract

Shift work is considered a risk factor for some health problems. This study aimed to determine whether night shift work is a significant factor for breast cancer risk. The case-control study was conducted from 2015-2019 in the Łódź region. The case group included 494 women diagnosed with malignant breast cancer; the control group included 515 healthy women. The research tool was an anonymous questionnaire. In the case group, the percentage of women working shift work was 51.9%, whereas in the control group, it was 34.1% (OR = 2.08 (95% CI: 1.61; 2.69)). A more insightful examination of shift work showed that only night work has a significant impact on breast cancer (OR = 2.61 (95% CI: 1.94; 3.53)). Even after considering the effect of other possible cancer factors (like high BMI, smoking, early menstruation, late menopause, pregnancy history, age, place of living, education), the odds of developing cancer were twice as high in the group of shift workers (OR = 2.20 (95% CI: 1.57; 3.08)). Considering a significantly higher risk of cancer among people working at night and a high percentage of such employees in Poland, the government should consider special action in the prophylactic treatment of cancers.

Keywords: breast cancer; occupational choice; public health; shift work; value of life.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Employed persons working at night as a percentage of the total employment in each EU28 country in 2018 (based on Eurostat). Source: own elaboration based on Eurostat data (tables titled lfsa_ewpnig).
See this image and copyright information in PMC

References

    1. Haus E., Smolensky M. Biological clocks and shift work: Circadian dysregulation and potential long-term effects. Cancer Causes Control. 2006;17:489–500. doi: 10.1007/s10552-005-9015-4. - DOI - PubMed
    1. Knutsson A. Health disorders of shift workers. Occup. Med. 2003;53:103–108. doi: 10.1093/occmed/kqg048. - DOI - PubMed
    1. Costa G. Shift work and occupational medicine: An overview. Occup. Med. 2003;53:83–88. doi: 10.1093/occmed/kqg045. - DOI - PubMed
    1. Fritschi L., Erren T.C., Glass D.C., Girschik J., Thomson A.K., Saunders C., Boyle T., El-Zaemey S., Rogers P., Peters S., et al. The association between different night shift work factors and breast cancer: A case–control study. Br. J. Cancer. 2013;109:2472–2480. doi: 10.1038/bjc.2013.544. - DOI - PMC - PubMed
    1. Kubo T., Ozasa K., Mikami K., Wakai K., Fujino Y., Watanabe Y., Miki T., Nakao M., Hayashi K., Suzuki K., et al. Prospective cohort study of the risk of prostate cancer among rotating-shift workers: Findings from the Japan Collaborative Cohort Study. Am. J. Epidemiol. 2006;164:549–555. doi: 10.1093/aje/kwj232. - DOI - PubMed

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