Association between night work and cardiovascular diseases: analysis of the 3rd Korean working conditions survey

Objectives: This study was conducted to investigate the relationship between night work and cardiovascular diseases among wage workers in Korea. Methods: The study was based on the 3rd Korean Working Conditions Survey (KWCS; 2011). This study included 29,711 wage workers. We used the chi-squared test and logistic regression to examine the association between cardiovascular diseases and night work and cumulative night work. Results: Among all of the paid workers, 12.5% reported doing night work >= 1 day per month. Night work was significantly associated with an increased risk of cardiovascular diseases (odds ratio [OR] 1.58, 95% confidence interval [CI] 1.11-2.25). Also, compared to the group that did not do night works, the group with higher cumulative night work demonstrated an increased risk for cardiovascular diseases (OR 1.81, 95% CI 1.19-2.74). Conclusions: This study suggests that night work is significantly associated with cardiovascular diseases.