关键词: 高胆固醇血症, 倒班, 不良生活方式, 生活方式, 相加作用, 钢铁工人

Abstract: Background　Abnormal blood lipids show an increasing trend of prevalence in Chinese adults，among which elevated serum total cholesterol is a key risk factor for atherosclerotic cardiovascular disease. Currently，there is no consistency regarding the association of shift work and dyslipidemia. The number of Chinese shift workers is growing，but the association of shift work and unhealthy lifestyle with hypercholesterolemia has been rarely studied. Objective　To explore the association of shift length and unhealthy lifestyle with hypercholesterolemia. Methods　By use of a cluster sampling，the workers of a steel mill attending the 2017 occupational medical examination were selected. A survey was used to collect their demographics（sex，age，height，weight，family medicalhistory，and so on），shift situation（shift time，age for initiating shifts，and so on），and lifestyle（diet，physical activity，smoking，drinking，and so on） using a self-developed Health Assessment Questionnaire. Restricted cubic spline（RCS） was used to analyze the dose-response relationship between shift length and hypercholesterolemia. RCS regression line with knots was used to divide the participants by shift length. Multivariate Logistic regression model was used to analyze the relationship between shift and unhealthy lifestyle with hypercholesterolemia. The additive interaction between shift work and unhealthy lifestyle was estimated using relative excess risk due to interaction（RERI） and proportion attributable to interaction（AP）. Results　The analysis with Logistic regression models with shift length（0，greater than 0 but less than 23.8 years，and equal to or greater than 23.80 years） incorporated as independent variables，and hypercholesterolemia as the dependent variable，indicated that the risk of hypercholesterolemia increased with the prolongation of shift length in groups with shift length greater than 0 in two models（P<0.05）. But hypercholesterolemia had no significant association with either physical activity or DASH diet scoreafter adjusting for age，sex，hypertension，diabetes，family medical history and other variables（P>0.05）. Given all factors，workers with three or more unhealthy lifestyles were 1.703 times more likely to have hypercholesterolemia than those with no or only one unhealthy lifestyle. Workers with more than three unhealthy lifestyles who worked shifts within 23.8 years were 2.527 times more likely to develop hypercholesterolemia than those who never worked shifts and had no or only one unhealthy lifestyle. Among those who worked shifts for 23.8 years or less，it was found that there was an obvious additive interaction between shift shifts and unhealthy lifestyles，in which RERI was 1.559（0.186，2.928） and AP was 46.26（4.36，88.17）. Conclusion　Both shift work and unhealthy lifestyle can increase the risk of hypercholesterolemia in workers，and they have an additive effect.
 

Key words: Hypercholesterolemia, Shift, Unhealthy lifestyle, Life style, Additive effect, Steel workers