Shift work is associated with metabolic syndrome in male steel workers-the role of resistin and WBC count-related metabolic derangements
Lu et al. Diabetol Metab Syndr
Shift work is associated with metabolic syndrome in male steel workers-the role of resistin and WBC count-related metabolic derangements
Yung‑Chuan Lu 3 4
Chao‑Ping Wang 2 4
Teng‑Hung Yu 2
IT‑ing Tsai 5 7
Wei‑Chin Hung 2
I‑Cheng Lu 0 6
Chia‑Chang Hsu 1
Wei‑Hua Tang 8
JerY‑iing Houng 9
Fu‑Mei Chung 2
Mei‑Chu Yen Jean 0 4 5 6
0 Department of Occupational Medicine, E‐ Da Hospital, I‐ Shou University , No. 1, Yi‐Da Rd, Jiau‐Shu Village, Yan‐Chao Township, Kaohsiung 82445 , Taiwan
1 Division of Gastroenterology and Hepatology, Department of Internal Medicine, E‐Da Hospital, I‐Shou University , Kaoh‐ siung 82445 , Taiwan
2 Division of Cardiology, E‐Da Hospital, I‐Shou University , Kaohsiung 82445 , Taiwan
3 Division of Endocrinologic, E‐Da Hospital, I‐Shou University , Kaohsi‐ ung 82445 , Taiwan
4 School of Medicine for International Students, I‐Shou University , Kaohsiung 82445 , Taiwan
5 Department of Nursing, I‐Shou University , Kaohsiung 82445 , Taiwan
6 Department of Occupational Medicine, E‐Da Hospital, I‐Shou University , No. 1, Yi‐Da Rd, Jiau‐Shu Village, Yan‐Chao Township, Kaohsiung 82445 , Taiwan
7 Department of Emergency, E‐Da Hospital, I‐Shou University , Kaohsiung 82445 , Taiwan
8 Division of Cardiology, Department of Internal Medicine, National Yang‐Ming University Hospital , Yilan , Taiwan
9 Department of Nutri‐ tion, Institute of Biotechnology and Chemical Engineering, I‐Shou University , Kaohsiung 82445 , Taiwan
Aims: There is increasing evidence linking a shift work schedule with various adverse health effects. The present study aimed to examine the relationship between shift work and the metabolic syndrome (MetS) in male steel workers, and also the possible mechanism of shift work‑ related metabolic derangements. Methods: A total of 1732 men aged 42 ± 8 years were enrolled in this cross‑ sectional study, including 862 day workers and 870 shift workers. Circulating levels of resistin were measured by ELISA using monoclonal specific antibodies. Results: The shift workers had higher rates of MetS and its components (central obesity, hypertension, and hypertriglyceridemia) than the day workers. In multiple logistic regression analysis, shift work was independently associated with MetS. In further analysis, the shift workers had elevated circulating levels of resistin (13 ± 10 vs. 10 ± 7 ng/mL) and total white blood cell (WBC) count (6.865 ± 1.819 vs. 6.304 ± 1.547 109/L) than the day workers. In addition, both resistin level and total WBC count were significantly associated with shift work, MetS, and its components (body mass index, fasting glucose, triglyceride, and high‑ density lipoprotein‑ cholesterol levels), and plasma resistin levels were significantly associated with total WBC count (β = 0.34, p < 0.0001). Conclusion: Shift work was independently associated with MetS in male steel workers. Resistin and WBC count were associated with shift work‑ related metabolic derangements.
Steel workers; Shift work; Metabolic syndrome; Body mass index; Fasting glucose; Triglyceride; High‑ density lipoprotein‑ cholesterol; Resistin; White blood cell count
Background
Shift work is defined that takes place on a schedule
outside the traditional 9 a.m.–5 p.m. day. It can involve
evening or night shifts, early morning shifts, and
rotating shifts [
1
]. Shift work is increasing worldwide, and
as many as 20% of workers in industrialized nations are
shift workers [
2
]. Shift work has been reported to disrupt
the circadian rhythm, sleep and work-life balance, and
to increase the risk of metabolic syndrome (MetS) [
3
],
coronary heart disease [
4
], mental and behavioral
disorders [
5
], and sleep disturbances [
6
]. The major function
of the circadian system is internal cycling of physiological
and metabolic events [
7
]. Many physiological processes
display a day-night rhythms, and feeding behaviour, lipid
and carbohydrate metabolism and blood pressure are
subject to daily variations.
The prevalence of MetS is increasing globally,
including Taiwan. The components of MetS including
dyslipidemia, dysglycemia, high blood pressure, and being
overweight/obese tend to cluster together, and they are
thought to be related to lifestyle habits including physical
activity, nutrient intake, alcohol consumption, and
smoking [
8–11
]. Few studies have examined the relationships
between shift work and MetS taking into consideration
the various factors associated with shift work that might
lead to MetS. In addition, shift work may be
responsible for increased body fatness and inflammatory
markers, higher blood pressure levels, and chronic low-grade
inflammation to play an important role in the
development of MetS [
3, 12–16
].
The detrimental effects of shift work on MetS and the
induction of inflammatory cytokines and associated
factors raise the possibility that shift work may increase
the risk of MetS. To clarify this hypothesis, we
investigated the association betwe (...truncated)