Joo JH. Lipids Health Dis. 2019 Mar 28;18(1):75.
Cardiovascular disease (CVD) is the leading cause of death in South Korea and is the cause of significant societal burdens worldwide too. A major risk factor for CVD is dyslipidemia, and its prevelance is also enhancing in South Korea, with reported rates categorising from 30 to 60%. Even though age, hypertension, and obesity, are better controlled and modulated today as compared to previous periods which are frequently known as risk factors for dyslipidemia. Hence, the enhanced prevalence of dyslipidemia is likely ascribable to lifestyle factors in South Korea. Night workers more likely encountered fatigue because of a lack of sleep. Even though this association is poorly understood, sleep deprivation has been recognized as a main risk factor for CVD. Night work seems to deliver as an obstacle to a healthy lifestyle and a threat to well-being, as circadian rhythm mismatch can damage sufficient sleeping and eating habits which causes poor health. An inadequate proportion of sleep and random eating habits may provide to the onset of dyslipidemia in night workers. Therefore, Joo JH et al., conducted a study to analyse and explain the correlation of dyslipidemia with night work.
The data was gathered from the 2013 to 2016 Korea National Health and Nutrition Examination Survey (KNHANES). 31,908 participants were evaluated. Eventually, 5813 participants (men: 2821 and women: 2992) were included. The dependent variable in the study was dyslipidemia and was determined based on the levels of total, high density lipoprotein (HDL), low-density lipoprotein (LDL) cholesterol, and triglycerides in blood samples gathered after 9–12 h of fasting. A work pattern was the main independent variable which incorporated three types: day, night, and other shifts. Socio-demographic, economic, health-related, and nutritional factors were also evaluated. According to occupational category, eating habits, and sleep duration a multiple logistic regression evaluation was used to estimate the odds ratios (ORs) with 95% confidence intervals (CIs) in three different models and to analyse the correlation among night work and dyslipidemia. A general linear model evaluation was also used to estimate the mean levels of the four diagnostic determinants (total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides), and the classifications and percentages of each were estimated.
A total of 816 (28.9%) men and 469 (15.7%) women had dyslipidemia. 76 (38.8%) from the 196 male participants, had dyslipidemia who were working at night, and the higher prevalence of dyslipidemia was shown in night workers than those who worked at other times (day: 684/2404, 28.5%; other shifts: 56/221, 25.3%). In the female participants, as 70 of the 379 women (18.5%) had dyslipidemia who were working at night (day: 382/2512, 15.2%; other shifts: 17/101, 16.8%). In the multiple logistic evaluation, the substantial correlation was observed among night work and dyslipidemia in male participants in all three models (model 1: OR = 1.58, 95% CI: 1.12–2.21; model 2: OR = 1.61, 95% CI: 1.13–2.29; model 3: OR = 1.53, 95% CI: 1.05–2.24) and in female participants, women with aged 50 years or older were more likely to have dyslipidemia as compared to their younger counterparts (50–59 years: OR = 1.61, 95% CI: 1.04–2.50; ≥60 years: OR = 1.66, 95% CI: 0.92–3.01). Male night workers who skipped meals were more likely to have dyslipidemia as compared to the day working counterparts (OR = 1.63, 95% CI: 1.00–2.67). Correspondingly, male night workers who had sleep for 0–6 h were more likely to have dyslipidemia as compared to their day working counterparts. Female night workers with white collar jobs showed three-fold risk of dyslipidemia than their day working counterparts (OR = 2.95, 95% CI:1.68–5.16). Thus, it was concluded that a substantial correlation of night work with dyslipidemia was found only between male workers. Besides, subgroup analyses of male workers who reported skipping meals or receiving < 7 h of sleep per night exhibited correlations of night work with dyslipidemia. A subgroup evaluation of white-collar workers of female participants found that night workers showed greater risk of dyslipidemia as compared to their day working counterparts. The development of future examinations was recommended to reduce dyslipidemia between night workers and to alleviate the burden of CVD in South Korea.
