2022 Volume 49 Issue 3 Pages 407-416
Purpose: Survey differences in lifestyle habits based on whether one has night shift work, and examine the relationship between lifestyle habits of male workers with night work and risk of colorectal cancer.
Materials and methods: Target consists of male workers who underwent lifestyle disease prevention medical examinations by the Japan Health Insurance Association between April 2016 and March 2017. Of the examinees screened for colorectal cancer, lifestyle habits such as diet, sleep, exercise, smoking, alcohol consumption, etc. of the 4,087 who had night work ("night work") and 28,668 who did not have night work ("no night work") were also investigated based on a specified medical checkup questionnaire and an original survey.
Results: Compared to the "no night work" group, the "night work" examinees had significantly higher response rates as to "skipping breakfast", "snacking after dinner (meal other than three meals)" and "eating dinner less than 2 hours before sleeping" regarding timing of meals. Meals that are "not well-balanced" and that "lack vegetables" were significantly high. Among the examinees with "night work", the percentage of those who get "sufficient rest through sleep" and the percentage of those who exercise were significantly low, and the percentage of smokers was significantly high. The percentage of "night work" examinees who have "no intention of making improvements" to lifestyle habits, such as through exercise and eating habits, was significantly high.
Discussion: Among night workers, it may be possible that lifestyle habits, such as diet, disrupted sleep patterns, lack of exercise, smoking, etc. promote disturbance of the circadian rhythm, contributing to increased risk of colorectal cancer.
