Korean J Fam Pract. 2018; 8(2): 299-306  https://doi.org/10.21215/kjfp.2018.8.2.299
The Association between Working Hours and the Metabolic Syndrome According to Occupation Group in over 30 Years Korean Men
Ji Young Kwak, Sang Wha Lee*, Hong Soo Lee, Kyung Won Shim, A Ri Byun, Sou Yeung Han
Department of Family Medicine, Mokdong Hospital, Ewha Womans University School of Medicine, Seoul, Korea
Sang Wha Lee
Tel: +82-2-2650-5165, Fax: +82-2-2654-2439
E-mail: ghwa@ewha.ac.kr
ORCID: http://orcid.org/0000-0002-7451-9978
Received: April 3, 2017; Revised: September 6, 2017; Accepted: September 13, 2017; Published online: April 20, 2018.
© The Korean Academy of Family Medicine. All rights reserved.

This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Background: We analyzed the relationship between long working hours and metabolic syndrome (MetS) in male non-manual and manual workers.
Methods: Using the Korean National Health and Nutrition Examination Survey data from the 5th to 6th period of the paid workers who were ≥30-years-old working for ≥30 hours/week were collected. Four weekly-working-hour groups of 30–39, 40–49, 50–59, and ≥60 hours/week were classified, using 40–49 hours/week group as the reference group. The relationship between working hours and MetS was evaluated for both non-manual and manual workers using multiple logistic regression analysis, after adjusting for age, smoking, drinking, exercise, final education, and sleep time. Additional stratification analysis was performed according to occupation and age.
Results: A total of 7,352 subjects were analyzed. In both non-manual and manual workers, there was no difference in the MetS incidence according to working hours. After adjustment, the odds ratios (ORs) of the MetS were not significant according to working hours in both non-manual and manual workers. In the stratification analysis, ORs were not significantly different according to working hours in groups of ≥40-year-olds and <40-year-olds of non-manual and manual workers, respectively, although ≥60 hours/week group showed lower ORs of MetS among ≥40-year-old service and sales workers (OR=0.534, P=0.024) and <40-year-old craft/plant/machine operators and assemblers (OR=0.466, P=0.037).
Conclusion: There was no increase in the risk of MetS associated with long working hours in both non-manual and manual workers.
Keywords: Metabolic Syndrome; Working Hours; Manual Worker; Non-Manual Worker
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