Night work, chronotype and risk of endometrial cancer in the Screenwide case–control study

Abstract

BackgroundCircadian disruption caused by night work has been associated with hormonal-related cancers such as breast and prostate cancer. Data on the role of circadian factors in the aetiology of endometrial cancer, an oestrogen-associated cancer, are scarce.MethodsWe examined the association between endometrial cancer and night shift work, chronotype (a characteristic correlating with preference for morning or evening activity) and sleep duration, in 180 incident cases and 218 hospital controls. Participants were interviewed face-to-face by trained interviewers to collect information on sociodemographic factors, familial, medical, occupational history (including work shifts), sleep duration and chronotype, and other lifestyle factors. We used logistic regression models adjusted for potential confounders to estimate ORs and 95% CIs.ResultsAfter adjustment by potential confounders, we found an inverse not statistically significant association between ever worked in night shifts and endometrial cancer (OR=0.64; 95% CI=0.35 to 1.16). Associations were irrespective of shift type (permanent or rotating nights) or duration of night work. We did not observe any statistically significant association between endometrial cancer and sleep duration, while inconsistent patterns were observed for chronotype and endometrial cancer risk.ConclusionsThese data do not support a role for circadian disruption in the carcinogenesis of endometrial cancer.

Morning chronotype and digestive tract cancers: Mendelian randomization study

“… 29 , 30 These associations were further strengthened in MR studies. 14 – 16 , 31 Being an early bird was also associated with the lower risk of other hormone-related cancers, like ovarian and endometrial cancers, 32 , 33 and lung cancer. 34 However, little data were available on association between chronotype and digestive tract cancer.…”

Causal associations of sleep traits with cancer incidence and mortality

“…This indicates that there is no causal relationship between insomnia symptoms and pan-cancer risk and that insomnia symptoms might be related to the increased pan-cancer incidence by interfering with multiple factors. Many conventional observational studies suggest that the evening chronotype is associated with an increased risk of some types of cancer ( Erren et al, 2015 ; Hurley et al, 2019 ; Richmond et al, 2019 ; Wang J. et al, 2021 ; Sun et al, 2021 ; Von Behren et al, 2021 ; Xie et al, 2021 ; Costas et al, 2022 ; Peeri et al, 2022 ; Yu et al, 2022 ; Yuan et al, 2023 ). However, only a few studies analysed the causal association between chronotype and cancer risk ( Richmond et al, 2019 ; Wang J. et al, 2021 ; Sun et al, 2021 ; Yu et al, 2022 ; Yuan et al, 2023 ).…”