The effects of exposure to night shift work on liver function: A cross-sectional study with emphasis of alkaline phosphatase enzyme.

Background: Previous studies have demonstrated that shift work can be significantly associated with adverse effects on liver function. However, the association between shift work and alkaline phosphatase (ALP) enzyme as a well-known biomarker of liver disease has been undefined. Methods: This cross-sectional study was conducted on a total number of 6,475 eligible oil refinery workers. According to shift work schedules, the participants divided to the following groups: 12-hr rotating night (n = 2,630) and 12-hr fixed day (n = 3845). The Spearman's correlation and logistic regression were applied to assess the association between shift work and ALP. Results: We found significantly higher levels of ALP in 12-hr rotating night compared to 12-hr fixed-day shift work groups (196.2 ± 52.1 versus 191.5 ± 53.4). According to quartile (Q) logistic regression adjusted by significant variables between study group (age, body mass index, fasting blood sugar, and total cholesterol), the odds ratio and 95% confidence interval of high (Q2-